I want to:
- Learn how to buy nesting software
- Should I Buy Nesting Software
- What Problems does Nesting Software Address?
Many times manufacturers are using an unsatisfactory nesting solution, and they think, "I know there must be a better way." And they are off to search for something better - sometimes not certain what that "something better" will do for them.
If you've had a similar discussion with yourself or associates, here are a few points to help frame your discussion internally and/or with potential suppliers.
Nesting Software Problems Solved
Nesting software tends to solve a multitude of problems, but they often fall into one or more of a few categories.
Beyond the basic functionality, nesting software can solve a number of second and third level problems accumulating significant benefits.
This brief list only scratches the surface of what you can expect from nesting software. So, far from just creating code or getting a new CNC machine operational , there is indeed “something better” that can improve productivity, lower costs, and deliver better fabrication results.
- Improve my Material Efficiency
- 10 Ways to Cut Material Waste
Nothing cuts into cash flow or is a profit drain like wasted raw material. And nothing is more frustrating than seeing huge piles of scrap go out the door. It is these real, tangible costs that, with some foresight and creative thinking, can be turned into rewards.
Here are a few tips to start you down the road toward material savings.
1. KNOW YOUR MATERIAL USE RATE
It is surprising in this age of technology how many manufacturers don't know their material use rate. They cannot easily answer the question, "How much of each sheet of material is used for parts?" or "What percentage of your raw material is scrap?" In some cases they need to grab a pencil and paper and do some quick estimates. And that's fine if that's where you are. At least it is a start. The best place to start when reigning in your material waste is getting a handle on what kind of scrap rate you currently have. When calculating, be sure to look at a large enough production sample to extrapolate use over six months or a year to get a truer picture of reality. Remember you can’t change what you can’t measure…at least when it comes to material waste.
2. DETERMINE A MATERIAL USE GOAL
What would be a reasonable goal to achieve? If you are currently getting 70% actual efficiency, is it possible to get 75%? What is a reasonable expectation for the processes - punch, laser, plasma – you are running? What would a 5% increase in material savings translate in to cost savings?
3. IDENTIFY SAVINGS CONSTRAINTS
What things hold you back from gaining more savings? Do you have really large parts that don't lend themselves easily to nesting? Are you working with a grained material that impedes rotation on a nest? Is there a limit to the amount of time you can spend (manually) nesting to achieve higher efficiencies? Do hot parts and rush orders mess up your efficiencies? Are you shearing blanks? Make a list.
4. IDENTIFY OPPORTUNITIES FOR SAVINGS
Now look for ways to reduce raw material costs. Have you evaluated all of the opportunities? Could savings be achieved with a smaller inventory on hand and ordering as needed (just in time)? Is it possible to purchase fewer sheet sizes in greater quantities and get a better price on standard sheet sizes? Is it possible to get better use out of your more costly materials? Would there be savings opportunities if your production time window was opened to include more future orders? Could nesting automation improve your efficiency?
5. MAKE USE OF THE TRIM STRIP
The trim strip on any piece of sheet metal is a golden opportunity to improve material usage. By placing additional parts in what could be a 3-4" strip the length of the sheet or nesting beneath the clamps, you can increase your material usage significantly. Be certain to make accommodations for the clamps and any repositioning necessary.
6. NESTING PARTS IN HOLES
Any part with a void or "hole" is an invitation to increase efficiency. Take every chance to place suitable parts in the holes. Doing so can make excellent use of scrap material and realistically take your actual efficiency for the sheet over 100%. Look for opportunities to mirror parts or create 180° pairs to increase the compactness of the part and fit additional parts in the holes.
7. COMMON EDGE CUTTING
By placing parts with similar straight edges together in a laser cutting environment you can save not only material but cycle time with common edge cutting. The reduction in material between parts can save as much as 15% on a sheet of material. Be certain to program the part path to avoid freed parts and potential head crashes.
8. COMMON EDGE PUNCHING
In the same manner as with laser cutting, parts with similar straight edges or like radiuses can be punched simultaneously saving material and tool wear. By programming the same tool, i.e. a 4-way radius or rectangular tool, to strike two part edges with one hit, the material that would otherwise be between the two parts is eliminated. Common Edge Punching
9. FILLER PARTS
Filler Parts take advantage of non-priority parts to make excellent use of sheet material and reduce waste. There are many strategies to make effective use of filler parts, but here are a couple.
Alternate materials - when creating a nest on a high grade material, i.e. brushed stainless, take advantage of parts that would otherwise be created on a lower grade material to fill in the balance of the nest or sheet. The result is less of the higher grade material is wasted.
Stock Inventory/KANBAN - If you regularly produce stock inventory of small parts, such as brackets, introduce them into your nesting process. The inventoried parts can be nested amongst the active orders to reduce waste. The key to this process is keeping track of your inventory part levels and knowing what quantities to produce when. Nesting software can aid with that.
Future Orders - In a perfect world each sheet of material has 100% or greater efficiency using only the most urgent parts due today. But that isn't always possible. However, material waste can be significantly reduced by looking forward in time at the orders due tomorrow, next week, next month and bringing those part orders into the current sheet layout. You are not only meeting deadlines on those parts in advance of their due dates, but you're increasing material efficiency.
10. REMNANT MANAGEMENT & NESTING
A remnant is a large segment of sheet material left over after parts have been cut from the sheet. This can easily account for significant waste if not handled effectively. Ideally, each remnant should be saved and identified as a unique material (type & size).
Then as the next opportunity for creating a nest on that material arises, the remnant is given primary consideration for use. The faster the remnant is consumed, the less chance there is of sheet damage or loss.
11. BATCH NESTING
It goes without saying that the greater the part selection in a dynamic nesting environment the more opportunities a programmer or nesting software will have to find optimal part combinations and thus increase material efficiency. That’s exactly the concept behind batch nesting. Throw a bunch – a batch – of your most urgent parts in an “order bucket” and nest. Make lots of nests. And they will inevitably have a higher efficiency than creating a nest with a smaller dynamic part selection. Don’t want to be locked into running a series of nests in case something happens and you need to change something? Run the batch. Toss (delete) any nests that haven’t run on the machine. Make the change. Batch nest again.
How about you?
What are your approaches to getting the most from each sheet of material? What’s working? What isn’t? Share your ideas.
If you’d like to talk more about any of the ideas above and how they may work in your shop, contact us.
- How to Optimize Sheet Metal Sizes with Nesting Software
Managing sheet inventory is one of the many ongoing challenges for fabricators. They don't want to consume their cash flow and floor space with too much inventory. Likewise, no one wants to impede production by not having what is needed readily available.
Specifically, the first challenge is to have sufficient sheet quantity on hand. The second challenge is to have the right sizes available. The right size is defined as sheets sufficient in area to meet the need, but not too large or ill shaped that there is excessive scrap.
Engineers and programmers have struggled with this problem since the dawn of fabrication. And there isn't an easy solution to it, unless or until you turn to nesting automation to provide the answers.
The Case of the Shipbuilders
The right-sized sheet problem plays out on a very large scale for builders of ocean-going vessels. Here's the challenge they face. The plate material they are cutting is 0.1-8" thick. Because their product is mostly steel, raw material expense is very high - so there is no room for waste. In order to reduce the waste, they order custom plate sizes directly from the steel mill. There is a six month lead time from order to delivery for their material. Their process is to first complete the design of the metal parts of the ship and nest these parts while the remainder of the design details is being completed. This allows them to customize the plate size to the nest with a special feature called plate cutback. This feature starts by providing the nesting system with hundreds of discrete plate sizes to pick from. The nesting software picks the best plate size for the parts being nested and then if there is any waste at the edges of the plate, it cuts the plate back to a perfect fit. This process helps attain the highest possible material efficiency, but at a cost that only very large volume producers can afford. First the plate sizes are custom and will cost more per pound than standard sizes. The second cost is that the plate must be tracked from receiving into production to make sure the correct parts are cut from the plate. Finally, this process requires long lead times be built into the production process; in the case of shipbuilding, this is not a problem, but most products are produced in much shorter time frames.
This planning process allows them to know what size and how many plates the parts they want to cut will need long before the torch is fired up and parts are cut.
The Sheet Size Selector
It is possible to do something similar and avoid the some of the problems of the ship building model. The extra cost for sheet and plate sizes are mostly associated with the width of the material. This is due to the fact that steel mills like to produce in quantity and offer best pricing on standard width material. Most flat steel begin as a coil of a certain width. Sheet stock is produced by a cut-to-length process that sets the length of the sheet. This cut-to-length process is often done after the coil leave the steel mill. The cost of changing a length is small compared to the cost of changing the width of a coil previously produced. This means that custom lengths are much more cost effective that width changes.
Using this fact, a strategy of allowing the nesting software to select the optimal length is a practical way to determine what lengths with standard width should be inventoried.
If you are lucky enough to have a cut-to-length coil line, it is even possible to customize the length for every nest. If not, you can select an optimal set of lengths from a large range of lengths that fit you machines and your parts optimally.
Selecting from standard widths is also included in this process. The result is a set of sheet sizes that fit your part set optimally.
One drawback of this process is that you must know the part mix you will be produce for long enough to purchase and stock the raw material.
Working with Your Steel Service Center
Another approach is to build a relationship with your steel service center where they keep the various coil widths you need in stock. If the steel service center can deliver quickly, order the optimal width and custom lengths as you need them. If delivery times are too long, select a group of sizes and keep the minimum amount of inventory of each size and reorder as you use each size. The nesting software will pick the optimal size from your available stocked sizes. As you nest on material, the sizes you use most will be replenished as you reorder; this will allow you to keep a low inventory on site that is dynamically replenished by your steel service center. The result will be an optimal mix of raw material.
There is no need to guess about something as costly as material inventory when there are tools to quickly and easily get the answers you need to make informed decisions.
How about you?
How do you forecast material needs? What tools do you use? How is it working for you?
If Optimation can be of assistance in better managing your material inventory, contact us.
- Four Ways to Maximize Yield on Remnants
Sheet metal remnants (a usable piece of material remaining after parts are cut from the sheet, often referred to as “drop”) are the bane of every programmer and shop's existence. They are a pain to inventory, difficult to handle because of their odd shape, and a constant reminder that they need to be used or wasted.
This article offers some hope to the beleaguered programmer and operator. There are ways to avoid having remnants in the first place, and if all else fails there are tools to help quickly dispose of them with little effort.
Here we go.
How to Avoid Creating Sheet Metal Remnants
As we all know the best remnant is no remnant. In a perfect world all the parts would fill every sheet completely, and we wouldn’t have to deal with this challenge. A zero-remnant reality may not always be possible, but there are two strategies that help avoid creating remnants in the first place.
1. Using Filler Parts to Manage Sheet Yield and Reduce Remnants
Filler parts are parts with a less than urgent priority. They are parts that can be made now but are made from scrap or material that would be a remnant. There are three strategies commonly used to manage filler parts.
Filler Part Strategy #1 - Part Inventory
Creating part inventories from scrap or remnant material is the first strategy for filler parts.
Sometimes manufacturers carry part inventories of stock items to reduce setup costs or order response times. Alternatively, their production line may integrate a Kan-ban system, where part orders are cued when the part "card" indicates a need to replenish the stock.
In either approach, these parts are ideal filler parts. When a nest has unused material, extra space on the nest or material that would otherwise be a remnant can now be filled in with parts that will be used for inventory without preventing urgent parts being produced first.
Intelligent nesting software will report back to the order or scheduling system the number of parts created for each stock item. The scheduling system will then update the "quantity needed" before any additional parts are ordered to avoid overproduction.
Filler Part Strategy #2 - Higher & Lesser Grade Materials
Many manufacturers use multiple grades of material; some more costly than others. In the case of a manufacturer of industrial kitchen equipment, he may use brushed stainless steel for the exterior, visible surfaces of the cabinets and a plain finished stainless for the unseen back panels and interior parts. The brushed stainless is more expensive, but it has the same structural properties as the plain finish, so it is more than adequate as a replacement (filler) material for the plain finished stainless.
The second filler part strategy is to make good use of all of the higher grade material scrap whenever possible. To do this the manufacturer can use the scrap or remnants of the higher grade material to make parts that would otherwise be made of a lower grade stock by treating them as filler parts for the higher grade stock. In the case of the kitchen equipment manufacturer, he would make back panels and interior parts out of the brushed stainless - only when the material would otherwise be a remnant or scrapped – to prevent the expensive material from being wasted. At the end of the nesting process, the nesting software would know how many of the secondary filler parts were and were not nested. It would return the remaining quantity to their normal, not filler, order status on the plain material.
Expensive, high grade material destined for the scrap bin has been salvaged and made into usable product components. And expensive, high grade material remnants have been avoided.
Filler Part Strategy 3 - Future Orders
Consider a nesting environment where the engineer wishes to produce all of the parts due today only. In the case of batch nesting (creating a series of nests for multiple sheets of material from one set of part orders), as nests are built, the number of parts remaining gets smaller and smaller. Toward the end of this nesting process there will be fewer parts to nest and the nest efficiency will decrease; this is known as tail-off. It's also where remnants are created.
To increase the material efficiency, the programmer can allow the nesting software to look ahead at tomorrow's orders and treat them as filler parts. The nesting software will only include the filler orders in locations in the nest where material would otherwise be scrapped, such as a remnant. Today's orders will be the priority and will be nested first, and tomorrow's orders will fill in the scrap areas. This strategy blends the end of today's production with the beginning of tomorrow's production in a smooth and material efficient series of nests. And the opportunity for remnants is minimized.
2. Using JIT (Just-in-Time) Nesting to Avoid Remnants
JIT Nesting is all about creating nests just as the machine that will produce the parts is ready for them - just in time. The architecture behind this process is a never ending, always filling, real time order bucket reflecting the most current production demand. As new orders come in they fill the order bucket. As the machine (punch, laser, plasma, etc.) is ready to produce, the nesting software empties the bucket. Orders and products are coming in and out in a constant flow of production - meeting needs just-in-time.
How this helps minimize or avoid remnant production may not be self-evident. The secret is constantly keeping the orders coming in so that there is never a tail-off of orders, which usually creates a remnant.
JIT nesting in practice is similar to the Future Order Filler Part strategy when used with batch nesting. The difference is the "future orders" for JIT nesting are the orders needed for the very next nest. Whereas the "future orders" for batch nesting may be the 2nd shift production or tomorrow's orders. The window for "future" with JIT nesting is a very tight single machine cycle.
Therefore, each nest will have the advantage of pulling from the greatest pool of orders to provide the optimal sheet material efficiency.
How to Optimize Sheet Metal Remnants
As mentioned earlier, it's hard to imagine a zero-remnant world. So, in those cases where remnants are inevitable, here are two strategies to best manage them and make the most of this extra material.
3. Automatic Remnant Management
Advanced nesting software has the ability to automatically manage remnant creation, nesting, and use for the programmers and machine operators. The process starts when a sheet is identified by the software user as having sufficient material to create a remnant. The user can tell the nesting software to then generate an electronic remnant with a straight edge cut or a stepped-edge cut (see image above) to free it from the consumed, nested material. The software then creates a unique material ID for storage among the material available to nest on. When more parts are ordered the user or the software can "call down" the remnant by its ID, nest parts on it and send the finished nest to the machine operator as normal.
With this approach remnants aren't lost in the system and risk damage or being scrapped.
4. Irregular Remnant Management
Not every remnant can be squared-off to a rectangular or stepped-rectangular shape. Sometimes there are irregular-shaped remnants that result from a very large, odd-shaped part being extracted. In these circumstances, automatic nesting software can treat the irregular shaped remnant in the same manner as a regular-shaped remnant by storing it, labeling it, and retrieving it when needed for use. For more on irregular-shaped remnant management, see this article.
There is no reason remnants should present the problem that they often do. There are sizable material efficiency gains to be had with effective remnant management and the application of dynamic nesting software.
How about you?
Are remnants an issue in your shop? How do you manage them? What's working, and what isn't? Do you have any creative solutions?
If you'd like to talk more about the remnant strategies discussed here, contact Optimation.
- Nesting on Irregular Sheet Metal Remnants
Nesting on irregular-shaped remnants can make a significant difference on material yield. And if you are a manufacturer focused on reducing waste and improving yield, here's a nesting strategy that could prove very helpful.
Manufacturers often have to create large, non-rectangular parts in small quantities. These parts can and do fill the majority of the area on a metal sheet; however, they still leave a sizeable amount of usable space inside voids and around the exterior. This usable space, or remnant, isn't necessarily rectangular, as many remnants are. The remnant naturally follows the negative contour of the single large part removed from the sheet.
Irregular-Shaped Remnant Nesting Challenges
When a programmer is faced with an odd-shaped, sheet metal remnant he is challenged with a couple problems in attempting to use the material efficiently.
1. The programmer can't simply type in the X & Y coordinates of a rectangular sheet or remnant. The irregular sheet isn't rectangular.
2. The cutting equipment can't "see" where the hole in the material is to avoid cutting there. Not able to cut around the void safely, the programmer risks head collisions and damage to the equipment.
Programming Work-Around Strategies
There are a few work-around strategies the programmer and/or equipment operator can use that would solve the challenge with varying efficiency results.
1. The irregular-shaped material could be cut down to a rectangular shape consistent with its largest "x" and "y" dimensions. The interior voids, which may be sizeable, are discarded. This makes use of at least some of the sheet, but wastes the interior void material.
2. The remaining skeleton could be manually measured and programmed into the nesting software to be "seen" as an irregular shaped sheet. The software could then create a sheet layout or program to use the material. This makes use of more of the material but takes valuable programming time.
The Nesting Automation Alternative Strategy
In a perfect world, there would be no remnants because the sheet metal software intelligently optimized all of the sheets of material. However, we know that isn't the case. Large, odd-shaped parts will continue to create a special nesting challenge, and remnants will persist.
So, the next best solution to the complete absence of remnants would be nesting software that automatically captures the digital shape of the irregular skeleton - the exterior dimensions and the interior voids. Then automatically labels it as a unique material shape, and automatically recalls it when parts and orders seem viable for nesting on it. In this approach, the irregular skeleton is optimized for the maximum material available. Additionally, the programming time involved in creating and using the nest is negligible to non-existent. The user gets the best of both worlds – high material yield and minimal material waste.
The Amazing Shrinking, Reused Remnant
Additionally, the irregular skeleton could be cut, nested on, and saved repeatedly as the material is consumed with single parts or small quanitites not completely using the sheet. Each time the remnant shrinks. Imagine this material is rarely used, and large parts are cut singly. So the first large part is cut. The irregular remnant is saved. Then a couple more, smaller parts are cut from the first irregular-shaped remnant. The new, second-generation irregular-shaped remnant is saved, labeled, and stored for nesting a third time. This process can repeat indefinitely until the skeleton is so small as to be of no further use.
Again, the material is well used and the programming time is nominal.
Bottom Line Savings
Manufacturers who handle large, odd-shaped parts don't have to give up on material efficiency or simply wish they had customers longing for lots of little parts they could use as fill-in. With the right nesting software, and a remnant-capturing plan, multiple percentages of material efficiency can be retrieved where none was thought possible - or easily managed - previously.
Are you challenged with nesting large odd-shaped parts? What solutions have you found? Is material yield a concern? Share your story.
For nesting software with the power to handle irregular-shaped parts, contact Optimation.
- Sheet Metal Nest Efficiency Figures - What Everybody Ought To Know
Here’s A Quick Way To Understand Sheet Metal Nesting Efficiency Numbers
Why Manufacturers Track Material Efficiency
Manufacturers track their material efficiency for a few reasons. They follow efficiency numbers as a means of keeping an eye on day-to-day costs. They look at variances in their material efficiency numbers to see if any production changes (part mix, sheet size, trim allotment) have made a difference in efficiency. Finally, manufacturers frequently look at material efficiency as one basis for evaluating the return on investment when sizing up different sheet metal nesting software or CAM packages.
How to Measure Material Efficiency
We now turn to the task of measuring or calculating material efficiency. In doing so, there are a couple of numbers that come in handy when parsing the data. It's important to understand what these numbers are, when they are best used, and how they are calculated.
Actual v. Rectangular Nest Material Efficiency
Actual and rectangular efficiency are two terms that are tossed around in these discussions with the presumption that everyone is operating from the same dictionary. Today, we'll look at these terms, where and when they are used, and how best to interpret the data.
Actual Material Efficiency
Actual efficiency is the material efficiency calculated using the “actual” footprint or area of the parts. It is what you intuitively think of as the material consumption of a part. If the part is 6" x 6" square and without internal cutouts, the material usage would be 36 sq inches. Similarly, a solid circle would have a material consumption in inches of the total area of the part. (see upper right image) It's pretty simple to calculate when working with solid squares and circles.
If a part has a hole in it (see upper left image), the hole is treated as waste and isn't considered in the material consumed by the part. The footprint of solid part would be calculated, then the internal hole(s) would be subtracted. Think of a "donut" shaped part and you omit the "donut hole."
If a part is a solid crescent moon-shaped (see bottom right image), the external curves of the part - the actual part edges – are used to determine how much material is used for that part.
Actual efficiency is the truest sense of how much material is used and saved when a nest is completed. It is most common in contour nesting - but available in punch – and is calculated by sheet metal software that looks at the true or full shape of the part.
Rectangular Material Efficiency
Rectangular efficiency in contrast does not necessarily use the true, external perimeter of the part when determining efficiency. The only instance where the true, external perimeter of the part would be the rectangular efficiency - and the actual efficiency - is when the part is a solid rectangle. Otherwise, there will be a difference between the calculated actual and rectangular efficiencies.
Why Rectangular Sheet Metal Efficiency is Calculated
It may seem counter-intuitive to use any measure of efficiency other than actual. Actual as just stated is the truest measure of efficiency. Given this, there are circumstances where rectangular efficiency is either the only option or the natural choice.
Punch and Shear and Rectangular Efficiency
If your cutting environment is dominated by straight-edge cutting as in a shear, right-angle-shear, or punch/shear, the equipment "sees" and treats parts - regardless of their shape - as rectangles. The material is consumed in rectangular sections, even if the part is not a rectangle. For example, if your design calls for a circle-shaped part (see upper right image), and your tool is a shear, all of the material external to the circumference of the circle but less than the maximum height and width of a square surrounding the circle at its maximum diameter will be consumed as waste. With a shear no other parts can be put efficiently within this waste zone to improve efficiency. Therefore the circle's material usage is calculated as all of the material in the square surrounding the circle. It is greater than the actual material use of the circle itself, but the additional waste in this cutting environment is not escapable.
The practical application comes down to adequately billing the customer for all of the material used in the creation of his part, not just the material evident in the final part. Using this approach, the manufacturer doesn't assume the additional cost burden of the waste inherent in the production of the part.
Apples-to-Apples Material Efficiency Gauging Benchmarks
Calculating rectangular efficiency is so "20th Century" for contour and some punch processes. Because the actual profile can be cut easily with most contour (laser, Waterjet, router, plasma, oxy) or punch processes, the actual efficiency is the default measure of waste and material consumption.
However, you may still see rectangular efficiency quoted in head-to-head benchmarks in contour nesting. It is still used is because some nesting software packages still rely on a rectangular nesting algorithm to nest parts. [A rectangular nesting algorithm treats all parts as rectangles irrespective of their actual shape. It's not a problem if your parts are all squares. If not, it can be pretty costly because it can't take into account nesting options available when the actual part shape is considered.] So, even if the software manufacturer providing the benchmark results does not use a rectangular nesting algorithm - always be sure to ask - they may provide rectangular efficiency results for an apples-to-apples comparison with other software companies.
How Rectangular Efficiency is Calculated
In determining the rectangular efficiency of a part an imaginary rectangle is drawn around the part capturing the space at its largest dimensions (height & width). This may be the true perimeter if the part is a rectangle, but it wouldn’t be the case if it was the crescent moon-shaped part (see lower right image) mentioned above.
Efficiency Greater Than 100%
Have you ever seen rectangular efficiency quoted at greater than 100%? And while you're politely smiling and nodding you may be thinking "these guys are nuts." Their state of mind is for you to decide, but I can show you two ways 100% or more material efficiency is reasonable when using rectangular efficiency as your calculation model.
Sheet Metal Parts in Parts
When / if the nesting algorithm finds an opportunity to place parts inside of a void of another part such as a hole in a window-shaped part or donut-shaped part (see lower left image), there is an opportunity for rectangular material efficiency to exceed 100%. Here's the reason. The full area (length x width) rectangular footprint of the window is treated as used material for that window-shaped part, literally ignoring the void in the material, because there must be that amount of material consumed to create the window-shaped part. However - and this is key to seeing the 100%+ nature of rectangular efficiency - the area of the part placed inside of the window-shaped part is also counted as material consumed. The area of the interior of the window counted twice - once for each part. Thus, the opportunity for material efficiency to be greater than 100% is evident.
Part Rectangles Overlapping
Another circumstance that can lead to 100% or greater material efficiency is the overlapping of rectangles. Imagine if we nested two crescent-moon-shaped parts (see lower right image) by cutting the concave edge of one simultaneously with the convex edge of the other. But we treated each part as a rectangle to measure efficiency. The consumed waste of one part within the rectangle surrounding it would overlap the consumed rectangular waste or actual use of the second part. The some of the material would be again counted twice. And again, the opportunity for rectangular efficiency to be greater than 100% presents itself.
A Final Word About Sheet Metal Efficiency Measurements
So, we have two means of calculating material efficiency. Both are viable. Both have their place in assessing waste. The key for manufacturers is to know when and where each application suits them and understand clearly how the numbers are derived.
How do you calculate waste? Do you use actual, rectangular or a combination of both? Do you calculate waste? Let us know what you're thinking.
For a discussion on waste, measuring it or to compare your best practices to another solution, contact Optimation.
- 10 Ways to Cut Material Waste
- Improve my Capacity or Throughput
- Got Capacity? Nesting Software as a Capacity Maker
We were talking to an OEM (original equipment manufacturer) recently and discovered they had a double-digit number of CNC punch presses. Yet they couldn't keep up with the amount of work that was coming their way. Some would say, this is a good "problem" to have. Nonetheless, there was a clear bottleneck in sheet metal. And that problem needed to be resolved to keep the customers happy by meeting delivery times.
This manufacturer has several options to resolve his capacity issue. Maybe you can think of a number of them. We'll review some options here, and you can decide for yourself, what would be the best solution. Finally, let’s assume that turning the business now isn't an option.
Capacity Solutions for Sheet Metal Production
What does more capacity mean?
Greater capacity can mean a lot of different things to different manufacturers. What they do with the extra capability is all dependent upon the economics of their situation. Here are a few examples.
- More product can be produced with the existing equipment
- More can be accomplished with fewer machines and a smaller fabrication footprint freeing floor space for other operations
- New machine purchases can be put off until the demand is really warrants them
- Superfluous existing machines can be decommissioned or reserved for capacity peaks only.
- In the case of shearing before punching, the shearing operation can be minimized or eliminated, freeing up floor space, manpower, and speeding throughput.
In Conclusion .
The choice of how to increase capacity is a decision that will be unique for each manufacturer. What we have discussed today is that there are a number of solutions - including automatic nesting software - as tools that can add more "floor space" and get more product out the door. It is the savvy manufacturer that considers his options and chooses wisely.
How about you?
How are your capacity challenges handled? What solutions have you implemented? What advice would you give to someone in this situation? Let us know.
If Optimation can help you explore nesting software as a potential solution, let us know.
- Eight Ways to Gain Productivity
When sheet metal nesting every parameter, machine setting, order sequence, or part layout choice impacts nesting productivity – time & material.
There are countless sheet metal fabrication requirements to be considered when placing parts on a CNC punch, laser, plasma, waterjet or router. The design, the fabrication requirements, and the order sequence can have a significant impact on the quality of the nest. How well those requirements are respected when compiling a nest is at the heart of an effective sheet metal nesting strategy.
Let’s look some of the real world demands that these requirements place on a programmer when nesting, and more significantly, the tools and techiques available improve your numbers today.
Can the equipment produce the nest as programmed?
If the programmer does not take into consideration the machine requirements (reach, repositions, tooling stations, kerf allowances, etc.), the production may be stalled or halted to address unforeseen problems. Part quality may suffer, the machine may be damaged, and certainly production time will be lost. Creating a quality nest means taking into consideration the ability to produce it.
Best Practice: You can test a part or a nest’s ability to be manufacturered using the principles of concurrent engineering and test programming and nesting a part before it ever gets to manufacturing.
Does the tool path retain enough material integrity to hold the sheet together throughout the machine cycle?
If the skeleton falls apart before the parts can be off loaded, a potential hazard is created. Parts can come loose, tip up, fall through slats and get damaged. Parts or the machine can be damaged or personal injury can occur to the operator. Ideally, the tool path should be intelligently programmed to accommodate any manner of offloading with no risk.
Best Practice: Intelligent tabbing can be automatically achieved on a part by part basis or by using a minimum size parameter, i.e. all parts under X width get tabbed, to avoid mishaps.
Does the nest reflect the most priority parts?
Material efficiency is often an important priority when nesting. But sometimes, a "hot part" trumps material efficiency in terms of priorities. And even when material efficiency is the priority, are "hot parts" still effectively addressed in the nest? Optimal nests consider the real world manufacturing environment with all of its often competing priorities.
Best Practice: With automatic batch nesting a series of nests – not yet produced – can be discarded, a hot part inserted in the order bucket, then the batch is rerun. Achieving both material efficiency and responsiveness. Another approach is JIT nesting, where each nest is made in real time and reflects all current demand.
Are the individual parts within an order held together in the same or successive nests?
Order cohesion can be critical to managing the downstream production flow. If parts in one order are spread over multiple nests, which could be cut hours apart, the opportunity for part damage or loss increases. A nest should keep parts within one order together and have supporting documentation that identifies the status and location of each part and order for the operator.
Best Practice:Intelligent order management using smart sheet metal nesting software knows which parts belong together in an order and which orders have priority. The software can keep track of whether an order is new, complete or a work in process. Further, and taken to the next level, JIT Kit Nesting addresses the needs of keeping all of the parts of a single assembly together, so they can flow through the shop as a unit. Through intelligent nesting, the material efficiency can be managed to eliminate the end-of-kit efficiency tailoff and additionally reduce material waste.
Does creating the nest pose any potential physical hazards?
Slugs. Loose parts. Floating Scrap. These are all machine operator nightmares and an invitation for machine downtime. If the nest is not created to prevent their occurrence, any savings gained in material efficiency will be lost in rework and repair.
Solution: Again, strategic, automatic tabbing and intelligent nesting with collision avoidance can overcome these obstacles for the programmer and the machine operator.
Did the time spent programming the nest the justify results?
Sometimes programmers spend from 5 to 15 minutes to up to several hours programming a nest. The truth is the programmer's time is valuable and comes at a cost. Is an extra hour or two creating or manipulating a nest worth the additional material savings? Is there more value-added activities that he or she can be doing that makes a greater contribution to the value of the product? Depending on the cost of the material and the opportunity costs of the programmer’s time, it may be justified. But it is important to weigh all costs - including programming time - when evaluating a nest.
Best Practice: Programming time is just one of the many costs involved in nesting. Automatic nesting can drastically reduce that time and open up other opportunities to improve production with better use of the programmer’s time.
Is the nest meeting the ideal balance between all production requirements (material efficiency, programming time, throughput)?
When looking at the nest, it should reflect the priorities you have set for your production. And each manufacturer has unique standards. If material efficiency is the only criteria, then it should be the most material efficient nest possible. If programming or shop time, throughput, inventory management, or overhead are important, it should reflect these production demands as well. The challenge for sheet metal software is to find that perfect balance based on the priorities – all fo the priorities – you’ve set.
Solution: The optimal nest is a function of all of your priorities – response to change, efficiency, programming time, order priority, order cohesion, and more. Intelligent sheet metal software can dynamically balance these objectives and still keep you in control.
Is the nest material efficient?
I’ve mentioned it a couple times, but it merrits repeating because material efficiency is an important criterion. Does the nest make use of all material saving opportunities? Does the nest calculate part rotations at fixed angles (90, 180 degrees) or does it take full advantage of all angles, i.e. 123.574 degrees, to find the best part orientation. Does it create mirror parts, 180-degree pairs, or parts within holes? Does it take advantage of common cut or common punch situations to save material? Does it take advantage of trim strips through - in the case of punch - clamp repositioning? How does it handle tail off? Even a small percentage increase in material can return large savings.
At first blush the concept of a nest may seem simple – just layout the parts on the material, then cut. The art and science of producing the nest in an optimal manner to achieve all of these goals is where the real complexity lies. But, if you’re thinking broadly, taking in to consideration all of the variables, and relying on good, solid tools including a quality sheet metal software package, the complexity can be tamed and your results will meet or exceed your expectations.
What challenges do you encounter when sheet metal nesting? How’s the process working for you? Let us know what you think.
- Weighing Material Efficiency & Throughput
And depending on the nature of the manufacturing operation, there may be only one, clear, obvious choice. If you’re cutting expensive material, i.e. stainless steel, it would be common sense to save every last percent of material because waste is expensive and the cost only nominally retrievable. However, if you’re in a quick-turn-around shop where delivery is measured in hours, not days or weeks, you may be willing waste material just to meet the delivery requirements. If the customer is satisfied with your responsiveness and offers more business or is willing to pay more for the fast turn around, the monetary loss in waste can be overcome.
However, most manufacturers don't live in such a black-and-white world where there is only one, clear objective. Most wrestle with trying to achieve a bit of both simultaneously. What, then, do you do? How do you accomplish reducing material waste and increasing throughput at the same time?
Before we answer these questions, let's first understand the makings of throughput in a fabrication operation. Throughput as it relates to nesting and CNC fabrication is a function of two variables - programming time and machine time. Manipulating either of these variables will impact throughput, which we'll simply define here as how much product can come off the CNC machines in a given period of time.
These two leavers (programming and machine time) need to be synchronized. The machine optimally shouldn't ever wait for a program. Assuming the demand is there, the machine should run to optimal capacity for as long as needed. Similarly, a program shouldn't wait for machine time. The machines shouldn't be down, disabled, or otherwise off line - certainly because of a programming error.
Maxim: The longer programming takes, the longer a machine is down, the greater the drag is on throughput.
Understanding Material Efficiency
What tools do we have to drive material efficiency? Well, the first is the density of the parts on the sheet. How tight is the nest? How much skeleton is left after the parts are cut? The greater the density; the higher the efficiency.
But there are other - not so obvious - tools at our disposal to increase efficiency. Choosing the right sheet size can make a big difference in two ways. Some parts fit more optimally on one sheet size versus another. Knowing - or finding out - what is the best size sheet for any given set of parts can significantly improve material efficiency. The second silent benefit is the potential cost savings on raw material. It may be possible to transition from specialty size sheets to more common sheet sizes and save in purchasing costs.
There are ways to work-around these problems to achieve both material efficiency and throughput in a satisfactory manner. Some may use manual nesting to get high efficiency at the cost of significant programming time. Others may use static nests to get high efficiency with moderate programming time at the cost of reduced ability to respond to change. Finally, others may turn to single part programming (programming one part at a time) to respond to change rapidly at the cost of material efficiency.
The Optimation Solution
Optimation has nesting software, AxiomVE®. It is so intelligent that it can respond to change, significantly minimizing programming time by up to 90%, and optimize material efficiency, and increase throughput. It reduces machine downtime caused by poor programming resulting in 80 - 90% uptime. It uses dynamic nesting to respond to your priorities in the manner you would if you had the time.
- Best Practices Relaying Data from CAD to CAM
Today we spoke to a manufacturer, who shared with us his process of taking geometries from AutoCad® to his nesting package. It seems he exports them out of AutoCad, saves as DWG files segregated by material type, strips out all the non-cutting, non-tool path data by hand, and saves these edited files in another file for retrieval from the nesting software.
Maybe a piece or two of this cumbersome and frustration-ripe story resonates with your experiences or the experiences of another company you've heard about. It strikes me that in this scenario, there can be a lot of opportunities for error in passing manufacturing data from CAD to CAM by missing a step, grabbing the wrong file, or processing parts based on incorrect information. Ouch. If this rings even a little true to you, allow me to suggest a few alternative ways of looking at this process that could save significant time, error, and frustration.
Each and every manufacturer has their way of getting information needed for manufacture from design to production. And while no one way will be perfect for everyone, there are a few guiding axioms that may be of help.
The more files; the more errors
In any process where multiple copies of anything - let alone part geometries – are created, is a process asking for accidents. The engineer or programmer doesn't have a bulletproof system to know which file has the latest and greatest copy. He is left guessing or remembering or hoping a mistake wasn't previously made that will translate into significant downstream problems. The chance of him grabbing the wrong file is great. And we all know the snowball effect of grabbing the wrong part file and creating the wrong part, wrong version, or wrong size.
Best Practice Use one database for design. Have the nesting software draw on the CAD files for all part files. Don't store multiple design copies in CAD and CAM.
When the manufacturing data (material, grains, downstream processes, etc.) necessary to produce a part is stored in multiple places, the opportunity for mistakes is ripe. If the material is in the file name, the grain information is in the design file, and the post-fabrication processes are on a separate paper chart, the process is slowed considerably and, again, the opportunity for error is great.
Best Practice Agree on a standard set of naming and location conventions between design and manufacturing. Collect all of the relevant data in that same location, whether it is in the design file, a table within the design file, or within a separate table. The nesting software can then read all of the pertinent data automatically.
Proprietary file formats
Every CAD package has a proprietary file format. With AutoCAD it is "dwg." And this is all well and good. The challenge comes when passing off data to a CAM package. Because the proprietary file format is unique not only to that CAD package, but it also changes with every release. Integrating with a nesting algorithm becomes a moving target. Some CAM software packages overcome this by inserting a second CAD package in the process to convert the files to a format they prefer. See prior discussions about CAD package duplicity challenges Further, what do you do with all of the legacy files - the 500, 5,000, or 50,000 part files - that are in a proprietary format when you want to integrate with a CAM package that doesn't support the older version?
Best Practice Building and saving files in standard file formats (DXF or IGES), can make the whole communication link so much easier and opens up many more production options.
Stripping out non-cutting data
I have three dogs..that shed . a lot. I've long since given up trying to pick off the dog hair from the backseat of my car by hand. It's tedious, aggravating, and, well, tedious! Stripping out non-cutting data from a design file, in my humble opinion, is equivalent. Why manually edit all of the extraneous information? The opportunity for missing something that will impact production is huge. And the time consumed is non-value added.
Best Practice The best practice is to create a standardized format for manufacturing data that the design and manufacturing teams agree on and use with every design. For example, to communicate material type for each part, simply agree to a set of abbreviations for the material names, then put that abbreviation after the initials "RM" (raw material) in the design file. The nesting software can just pick up that information without human interaction. Similarly, if the grain information is needed in fabrication, insert a directional line in the CAD file on a separate layer. Again, the automatic nesting software will pick it up.
What are your experiences? How do you relay manufacturing data from CAD to CAM /nesting software? Do you have a best practice?
When looking to achieve nesting success there are best practices to draw on to minimize error, save effort, and reduce confusion. Contact Optimation to learn more about putting these best practices in place with automatic nesting software.
- Got Capacity? Nesting Software as a Capacity Maker
- Tame the Shop Floor Chaos
- Respond to Change in One Machine Cycle
We often hear from programmers and engineers about the hours upon hours they spend librarying parts, creating programs, and optimizing tool paths. Then they hope nothing changes in the schedule to disrupt their much-labored-over work. And you know how the story ends. Something happens - it always does - that throws the schedule into a tailspin, the nests are scrambled, the work starts over, and someone loses their lunch break just to keep the ball rolling. Meanwhile that equipment is still waiting; waiting impatiently with its metaphorical metronome ticking - loudly.
The solution to this time-and-time-again proven problem is simple. Just wait until the very last minute - seconds - before the laser, punch or other fabrication equipment has completed the current nest and the operator has unloaded it to create the next nest. That very next nest would reflect precisely current demand - orders, order quantities, part revisions, and material inventory - and prevent the dreaded last minute scramble to accommodate any and all changes.
It’s possible to do this. Really. Allow me to introduce you to "Just-in-Time Nesting."
What's Just-in-Time Nesting?
I'm sure you've heard of “JIT” or “Just in Time,” the Lean Manufacturing concept of producing products, delivering goods, or meeting demands "just-in-time" to reduce shop floor chaos, eliminate material waste, cut production time, minimize floor space, etc.
JIT Nesting is an advanced sheet metal nesting strategy that takes the same JIT concepts universally applied to the manufacturing process and focuses them on the nesting process to achieve much the same objectives. The JIT nesting process looks at the assimliation and integration of geometries and orders into nests in real time and pushes them to the shop floor within minutes or well under one machine cycle.
JIT Nesting is exactly what it sounds like. It is sheet metal nesting - creating a flat pattern layout of parts for 2D CNC cutting equipment - just in time. That would be just in time for the next machine cycle, just in time for the equipment to be optimized and not left idle, and just in time for all the priority orders, part revisions, and material inventory to be reflected in the next nest. Just in time to reduce chaos and preserve lunch breaks.
JIT Nesting Advantages
The advantages are clear. The machine operator or programmer now has the opportunity uneventfully manage a new part revision, a hot part, a damaged part, a new order, or some other chaos-inducing problem without disruption to the natural flow of production. Ah, relief. All of those changes are absorbed by the JIT Nesting strategy as a matter of routine. No issue is left hanging and no special order needs to be re- routed around or red-lighted through the fabrication process. Chaos is reduced. Normalcy becomes, well, the norm.
Eight Best Practices for Implementing the JIT Nesting Strategy
A successful JIT Nesting Strategy relies on a few tools and best practices. Here's a checklist of some of those requisite tools to review against your current environment to see if you're ready to roll out a JIT Nesting Strategy.
1. An Eye on Productivity / Efficiency Let's be clear, the JIT Nesting strategy isn't for everyone. But if you fall within one of several groups, JIT Nesting may be the solution for you. In a manufacturing shop where fast turn around, optimal throughput or productivity, and/or a large volume of parts/material are the case, JIT Nesting may be the solution to your production challenges. We've found that manufacturers already focused on demand-pull or JIT production are well suited to JIT Nesting. Any company keenly focused on reducing costs through lean manufacturing or a Six Sigma program are already disposed to integrating JIT Nesting. Finally, a manufacturer challenged with significantly long or short materials lead or product delivery times might be looking for a solution that wraps around JIT Nesting.
2. Basis for Justification Introducing the JIT Nesting Strategy may mean some costs – learning curves, process or policy changes, and maybe some technology investments. How to justify this change should be a question asked up front. Where’s the tangible savings? There are a number of financial bases you can touch on to build your justification. A) Material savings through reduced or eliminated remnants, better sheet metal nesting, introductino of standard or more optimal sheet sizes or reduction or eliminatation of batch nesting tail off. B) Improved machine cycle time from a reduction in machine set ups or elimination of wait time for nests which translates into more production. C) Reduced programming time by empowering the operator to in essence create the nests using automation.
3. Standardization. Your shop may be the definition of design and manufacturing process standards, or reaching the goal of standardization may be a work-in-process. Either way, it's very important to have design and manufacturing data standards to implement a JIT Nesting strategy. Why? JIT Nesting is an automated process of driving nests to the floor based on your priorities, your data, and your needs. It can only work if and when you have a consistent environment from which that automation can pull your priorities, your data and your needs and upon which it can build the nests. Think about having consistent file output formats, reliable material naming conventions, and dependable digital order requirement formats. If this JIT Nesting automation tool knows where and how to find the information it needs, it can and will do so automatically - in minutes and well under one machine cycle.
4. A Continuous Flow of Orders. A major component of the JIT Nesting Strategy is to keep the equipment going in an optimal fashion as demand requires, manage change, and eliminate the majority of the redundant programming efforts. If you have a backlog of orders or even just a steady flow of orders (per material), you have the makings of an environment for the JIT Nesting Strategy.
5. Dynamic Nesting The JIT Nesting Strategy relies on the ability to dyanmically nest and combine orders to both optimize the order process and material efficiency simultaneously. Without this flexibility – imagine JITNesting with static nests? – the strategy falls apart. The user would be asking the strategy to be flexibile and rigid at the same time. It won’t work.
6. Electronic Designs In the 21st Century CAD software is ubiquitous. The cost has come down and the need is so universal that virtually every manufacturer has some electronic design software. Pro-E/Creo, AutoCAD, and SolidWorks are just a few of the more common brands. In order to do JIT Nesting the nesting software needs to draw on (please excuse the pun) a CAD output file, where the design and, optimally, some manufacturing information reside. Electronic files are a low barrier-to-entry requirement for JIT Nesting, but a critical one.
7. Electronic Order File Not quite as common, but becoming more so, the order information - at minimum the quantity, material, and due date - are in a digital file. This can be as easy as an extract in CSV file format from an MRP/ERP system. Or it can be as simple as an Excel spreadsheet forwarded from Scheduling. Either way the nesting tool can pick up - and return - order data on the fly for efficient sheet metal nesting.
8. An Intelligent Nesting Software As you may have guessed, the JIT Nesting Strategy isn't an effective process without the benefit of some pretty capable nesting algorithms. The nesting tool needs to be able to nest fast and efficiently, respectful of demand changes, honoring order priorities, aware of part revisions, knowledgeable of material inventory, and even alert to equipment failure so as to drive nests to the next available, like-process equipment. The nesting algorithm needs to think intelligently on multiple dimensions and about multiple combinations of parts and orders within the constraints of your systems, your priorities, and your needs. Did I mention it needs to be "fast?" Without this intelligent nesting tool, the JIT Nesting Strategy would be virtually impossible.
How Does Just-in-Time Nesting Work?
Once you have all the tools and best practices in place, it is a matter of integration and automation. The user/operator pushes the button to call for the next nest. The JIT Nesting software / algorithm begins the process by querying the order bucket (electronic order file) for any new orders that have come in since the last query. (The time interval is set by the user.) It reconciles any new orders with the latest part library (created from electronic designs) checking for revisions and/or new designs. Next the JIT Nesting Software triages the orders by due date and/or arbitrary priority settings and funnels the most urgent parts into the nesting algorithm for dynamic nesting. Note: the nest isn't created solely on the basis of order priorities. Many other factors including material efficiency are weighed, again based on the user's priorities. The next nest - and only the next nest, meaning single sheet - is created, programmed, and sent to the machine tool. Once the nest is complete, the information about the orders processed on this nest is sent back to the order bucket and the work-to-do file is updated.
It's that simple. It's that automatic. It's done in less than one machine cycle.
Is the JIT Nesting Strategy a possibility for you? Do you see an application in your shop? Do you have or are working toward acquiring the necessary tools to make it happen? What's your story? Raise your hand and let me know.
For a broader discussion of nesting strategies read Understanding Nesting Strategies and Tactics.
For more information about JIT Nesting Software and a chance to talk to customers using practicing it today, contact Optimation.
- 4 Levels of Order Entry & Nesting Software Integration
One of the advantages of automatic nesting software is the ability to integrate with the existing order management or scheduling system (MRP/ERP) creating a seamless upstream and downstream information flow.
One of the concerns some manufacturing engineers have is what does this functionality mean to me if I'm not using an MRP/ERP system. Is it more than I need? Or can I start with a simpler method and work up to something more sophisticated with full integration and/or JIT?
The Four Automation Levels of MRP/ERP and Automatic Nesting Integration
The good news for all manufacturing engineers is that order entry integration with automatic nesting isn’t an on/off switch. There are levels of integration that you can dial up or down to suit your needs. Further, as your operation gains sophistication, you can keep up with it without making software changes. Automatic nesting software with MRP integration is a scalable tool that can grow with you and your needs.
Level #1 - Manual Order Entry - Users familiar with work orders or travelers as the method of communicating orders to the shop may feel most comfortable with this approach. The programmer or machine operator can simply key in the part number, quantity, and choose the material from a drop down or key it in for each order from any paperwork available. If warranted, additional information, such as job number or due date, can be also be entered with the order. The upside is a lot of control over the process. The user can independently set the priorities or production sequence as the orders come through. The downsides are the time consumed and the opportunity for error - a quantity of 5 parts can easily be 55 with one key stroke.
Level #2 - File Download - Some manufacturers have a bill of materials system or a spreadsheet where the orders and schedule are managed. Most, if not all, of these have the ability to export their part order data into an ASCII text file which is similarly formatted to and can be opened in a Microsoft's Excel® program. Any and all of the information mentioned above - part ID, quantity, material, due date, etc. - can be captured and downloaded with the orders into the ASCII file from the Excel or Bill of Materials System. With this data extracted to a file, the user can easily - without rekeying it - import it into the automatic nesting software. The entire order entry process for hundreds or thousands of orders can take a matter of seconds or minutes. The process does need to be manually initiated and managed. Often fabricators do this once or twice a day depending on the volatility of orders. However, it is exponentially faster and more error-proof than manual order entry.
Level #3 - MRP/ERP Integration - The next step in our scalable continuum is integration with the MRP/ERP system. For those fabricators leaning toward a JIT fabrication model and JIT nesting, this may be the process best for you. In this model, the automatic nesting software queries the MRP/ERP system at set intervals (every hour, shift, day) as set by the users, for new orders that appear in the MRP/ERP system. If new orders are found, they are downloaded to the nesting software for processing. The orders - again with the same information as above - are triaged based on either arbitrary priority settings in the MRP/ERP system or by due date. This ensures that the hottest parts are handled first, while at the same time the material efficiency, and order cohesion are maintained as well.
Level #4 - Full JIT Integration - For the fabricator fully embracing the JIT model, full JIT integration between the MRP/ERP system and the automatic nesting system would be a strategy worth investigating. In this model, the information flow is not only from the MRP/ERP system to the nesting software but the reverse happens, too. The nesting software reports back to the MRP/ERP software what parts have been nested and material used. The quantities used are then deducted from the "quantities needed" for both parts and material inventory. And in a real-time manner all systems are current with the realities on the shop floor.
So, the solution for any one fabrication operation may be different or as is likely with most organizations it may be an evolving process. The best solution for most is a product that can meet you where you are with your systems and needs today, and grow with your needs as your operations change.
How about you?
What kind of order entry system do you have? Is it manual or automated or some combination thereof? Is it working? What would you like to see? Join the conversation.
In the meantime, if you'd like to pursue this conversation, contact us. We'd be happy to talk.
- Respond to Change in One Machine Cycle
- Does Mixing Shop Orders Make You Nervous?
Does the thought of mixing orders in a nest strike fear into your heart? Or does it just feel better to keep your items separate, like food on a tray - no mixing allowed.
This probably isn't you, but maybe you've heard of others, who under penalty of death, will not mix orders when nesting. It's true. We hear about it a lot.
Although I'm having a little fun with it here, some have very real concerns about mixing parts from different orders, jobs, customers on a single or series of nests. And those concerns are probably based in real-world, nightmarish experiences.
Today, we'll look at the challenges of mixing orders and some best practices and tools to address them. Then we’ll consider why mixing orders would be beneficial when done right and with the right tools. Finally, we’ll ask the questions you may be asking to determine if mixing sheet metal nesting orders is right for you.
Challenges in Mixing Orders When Nesting
Shop Floor Chaos
The biggest concern we hear about mixing orders, jobs, customers or any other non-like entity in a nest is that it will - and does - wreak havoc on the shop floor. The machine operators are moving as fast as they can to keep the line going smoothly. When the orders are mixed coming off the nest, it simply adds complexity to their work to have to sort the parts by order, job, or customer and keep everything moving smoothly. And then there is the challenge of where to stack everything, once it is coming off the cutting bed.
Best Practice to Address Shop Floor Order Management Chaos
The shop floor chaos of managing orders resolves into two issues. The first is process-management. With the part, order identification system and the right visuals - plots and / or labels, and the right reports - the machine operator can easily identify the parts and orders. When the process is made doable, the task is manageable and shouldn't add to the job complexity. It should simplify it.
The other issue is a culture or mindset. If anyone, including myself, perceives that a job will be made harder and there is nothing in it for me, there will be pushback. I understand. That makes sense. The tool to leverage here is a clear understanding of the process, everyone's role in the process, and how the change will benefit everyone including the operator.
Another concern we hear about mixing orders is job costing. If the sheet isn't dedicated to an order, job, or customer how can the parts (machine time and material) be costed accurately? Or what if the customer supplied the material, then the job can't be mixed with anything else, because it is dedicated, customer-specific material.
Best Practice for Job Costing
The technology exists today to cost a job (machine time and material) by sheet and / or by part with the right nesting software. So, even if orders are mixed, the individual piece-parts can be costed separately and tied to their respective orders, jobs or customers. There is no reason to separate orders simply to be able to cost a job accurately.
Finally, if you are mixing orders, some say, there is no way to set priorities based on job, part, customer, order, etc.. I must put the orders through as whole orders in the order in which they are needed. How can you juggle orders, material and priorities and keep everything moving smoothly?
Best Practice for Handling Order Triage
Prioritizing jobs, parts, orders by their due date or an arbitrary status is easily done in conjunction with an ERP/MRP system or through manual assignment in an advanced sheet metal software product. The software can order the parts with the priorities or due dates you assign, and respect your need to obtain a satisfactory material efficiency.
Mixing Orders | What's the Benefit?
What would be the upside of mixing orders? Why would any manufacturer ever do such a thing? Would it be worth the effort?
One possible advantage for you of co-mingling orders (jobs, customers) would be an increased material efficiency. If there are more parts from multiple orders in the order bucket, then the sheet metal nesting software has more part options to work with when creating a nest. More part options naturally - assuming a variety of parts reflecting different sizes and shapes - would lead to increased material yield. For example, if the nesting software can look at 250 parts from five orders all with near-term due dates, it can choose from several options for each nest, and ultimately choose the best - again recognizing a number of priorities - due dates, material efficiency, and throughput. It's not always the case, but in this situation "more" parts is "better."
Manufacturers typically have some materials that get heavy use, and others that get light use. You may run 18-gauge aluminum all day long and only on occasion run stainless steel. If you were to mix the stainless steel orders from multiple jobs or customers, then the chance of a remnant or irregular sheet metal remnant would be minimized. Alternatively, with a greater density of parts from combined orders, the manufacturer could do some sheet size estimating or forecasting. With a clear window on future needs he can standardize the sheets, order in more favorable quantities, or move to a JIT sheet ordering system.
Grouping Like-Downstream Process Parts
In most operations there is at least one downstream operation performed on a part after nesting & cutting. Whether it's welding, painting, forming, assembly, or something else, there is a scheduling challenge to be managed. Some processes take longer than others, and ultimately all the parts for one assembly should come together at the same time.
By mixing parts from various orders but segregated by their downstream process, i.e. welding, the parts can be scheduled to give the downstream process plenty of time and still come together for assembly or shipping at the same time. Welded parts could be cut with a 2-day lead time, where painted parts may only need 1-day before assembly. Using this thought-process, the set up and tear down time for the downstream processes can be minimized because more like-parts are coming through at one time.
If the engineer is mixing orders, then he has the opportunity to introduce "filler parts." Filler parts can be "second class" parts that only are created in the sheet voids in and among the priority parts. They would, by definition, be a different order. This "second class" order may possibly have a later due date, a different first-choice material type, or may be made for inventory. Regardless, its urgency is less than the priority parts, and is treated as a subordinate order - a mixed in order. By using filler parts the engineer can increase material efficiency by making them out of material that would otherwise be scrap with nominal programming time.
Evaluating Order Nesting Options
So, we've assessed mixing parts and seen where there are indeed pros & cons to the strategy; challenges and best practices. This leaves us with a couple questions.
Do the pros outweigh the cons enough to consider this option? Ask yourself, what could be the gain in material efficiency? Is there a compelling argument? Could we reduce shop floor chaos by better timing the orders that go downstream? Is there an opportunity for filler parts to be introduced? Would filler parts save us time and material, if so, how much?
Each manufacturer has to assess independently whether mixing orders is a viable option. With good information at hand, access to nesting software able to meet the challenge, and an upfront discussion with the stakeholders involved in the process, a clear choice can be made.
How about you?
How do you handle a variety of orders? Do you have a solution to some of the challenges presented here? Maybe a best practice to offer. Share your ideas.
For more information on sheet metal software capable of handling mixed orders in a dynamic nesting environment contact Optimation.
- What Problems does Nesting Software Address?
- Should I Buy Nesting Software
- How to Justify a Nesting Software Purchase
- Financial Justification
- How to Financially Justify a Nesting Software Purchase
Most project managers we meet, who are tasked with investigating a nesting software purchase, inevitably come to the fork in the research road where they need to make a case for the software to the boss. Those who come equipped to management with an argument for why and how the nesting software will pay for itself in a short period of time, come out ahead for their efforts.
The question then becomes, how does the nesting software pay for itself? Or you may be asking, really, can the nesting software pay for itself? The answer to both questions unfolds several ways.
We'll break the ways to make that case for cost-justification down here.
What is the old adage in real estate? "Location. Location. Location." Well, something very similar can be applied here. Although it's not the only way to justify a nesting software purchase, material savings is the approach most often taken and not one to overlook. So, we could say "material, material, material" is the first place to look for cost justification.
Nesting software can, in most circumstances, demonstrate a multiple percentage reduction in material use. That is, a manufacturer can see is material usage drop by 5% to 15% in relatively short order with the use of effective nesting software. That percentage when multiplying it times the cost/pound, can easily represent the monthly expense saved through nesting software. It's important to notice that these are hard costs, real expenses, which are measurable and can be clear witness to the impact the nesting software is having on the amount of material used. A perfect basis for cost justification.
How do you know how much material a nesting software will save? Ask for a benchmark to be done.
Streamlining the Fabrication Process
Throughput or productivity in this discussion is about the amount of product that moves through the shop and out the door within a given period of time. Impediments to throughput or productivity come in many forms. They can be additional processes, i.e. shearing before punching. It can be the number of machine set ups as a function of changing sheet sizes or turret configurations, which are time consuming. It can be the hassle and time-involved material management such as loading and unloading, transporting sheets from one process to another, stacking and/or counting sheet inventory.
Automatic nesting software can minimize or eliminate redundant or additional steps streamline the process and increase throughput. If the machine operator changes out the turret fewer times, if there is less need for shearing, if there is fewer sheet sizes to manage, time and money is saved. Because it is measureable time, which can be multiplied times the labor costs, it can be the basis for a cost justification for nesting software.
Optimizing the Cut Path
Another method to achieve greater throughput is by looking at the cut path or tool path. This is the time and distance used by the cutting head or turret to cut or punch the entire sheet. Logically, the shorter the distance from start to finish the faster the cut time and the greater the throughput. Automatic nesting software can optimize for this benefit. Further, the time and distance can be measured and compared to existing practices with the help of a benchmark - yet another tool for a cost justification.
Programming Time Savings
Sometimes the significant (up to 90%) savings in programming time can be used as justification for the nesting software purchase. There are three ways to find the cost savings here. 1) When engineers are at or exceeding capacity and either their time could be more cost-effectively used elsewhere then the better use of their time can be a basis for justification. 2) When engineers are unable to keep up with production demands and productivity and throughput suffer, then improving the speed of programming can and does increase throughput (capacity), which can be the basis for justification. And finally, 3) if the demand on programming is so great as to incur overtime costs, employing nesting software to expedite the process and reduce overtime can lead to direct, justifiable savings. The best way to quantify the time savings is to benchmark or test the programming time in an alternative software, then use those numbers to compare to the present situation. The difference is the justification.
In Conclusion -
As we've seen here there are several ways to meet the needs of the decision makers when looking for a cost justification for a nesting software purchase. The answer may mean looking to one or more of these approaches, running the tests, doing the analysis and creating a cohesive, compelling argument. If that sounds daunting, that's okay, there are experts at Optimation, who travel this road every day and can help.
How about you?
Are you looking to build a case to justify nesting software? What's your approach?
If Optimation can help you build a justification, please contact us.
- Four Secrets to Profiting with Nesting Software
Why would a fabricator consider, let alone implement nesting program? What's in it for the manager or the shop personnel to invest in a CNC nesting program? There’s got to be ways to profit from this investment, why else would someone go down this road.
Let's be upfront. Changing or introducing new software into the work environment means, well, change. And there are costs to making such a change. Beyond the monetary investment there is the time and effort invested in the research and implimentation. So any sound reasoning would lead us to believe there must be a profit at the end of the process to make that experience worthwhile. There needs to be benefits for the whole team - managers and shop personnel – to justify not only the expense but the transition time and effort.
If you've ever thought about using - or upgrading to - an automatic, dynamic nesting program you may be asking yourself, "what's in it for me?" If so, some of the following secrets to profiting may ring true to you - or they may be the catalyst you are looking for to talk to the boss about nesting programs. If you've not considered automatic nesting program, look to the list below for a new idea that might spark a very interesting discussion.
Nesting Programs | Financial Return through Nesting
1. Programming Time
An automatic, dynamic nesting program can and will cut programming time by up to 90% as compared to manual or interactive nesting and part programming processes. How? Truly automatic nesting program slashes repetitive actions commonly found in CNC programming. By eliminating the repetitive actions the programmer not only saves time but greatly reduces the opportunity for error. Let's briefly review the three main areas of fabrication CNC programming that can be dramatically impacted by dynamic nesting and part programming.
With a manual or interactive process the programmer drags & drops or imports one part at a time. Every part needs to be reviewed for manufacturability. Every part needs to be touched. With automation - or batch input - these steps and more are eliminated. One to one thousand parts can be imported and reviewed along with their manufacturing attributes in seconds or minutes. Time Saved: hours.
How many production orders do you get each day? 5, 50, 500? Each one has to be communicated with the right parts, the right due date, and the right material and quantity to the nesting program. For most manufacturers this process takes time, and for some, a lot of time to complete accurately. With an automatic link between the nesting program and the order entry system, this manual process can be completely eliminated. There's certainly no need to key some information into CAM software if it already exists electronically. Connect the two and save hours of repetitive work.
Orienting each part on a sheet to respect is required grain, optimize the material, avoid collisions, account for pierces, leads, trim, clamps, and on and on is hugely time-consuming - not to mention error-prone undertaking. One of the central tenants of advanced nesting program is the automation of this process. Intelligent software knows the variables for which to account, understands and even thinks through its options, weighs the various outcomes, and independently determines the optimal result. In seconds or minutes a nest program can create a workload for one or more cutting machines for an entire day's work. Time Saved: hours.
2. Material Yield | Material Efficiency
Typically, manufacturers zero in on material savings when seeking to justify a nesting program purchase. It's true. Automatic nesting program can save 5-15% in material, which in most cases can result in a 6-12 month payback on the investment. Where saving programming time may get the attention of the programmers and operators, material savings may be the easiest means to justification simply because it is so tangible. Why? Material savings are hard, real, highly visible costs. You can see the change in how much you're purchasing or how much you're sending to the scrap dealer each month. You can see how big - or small - the scrap pile or the scrap revenue is. Unlike saving programming time, which is typically consumed by another - hopefully more productive – task, there is a clearer, more concrete benefit with material savings.
How do you save material with automatic nesting program? There many ways to save material through advanced nesting program. From more efficient nests, to part order strategies, to making fuller use of or eliminating remnants, to maximizing the trim space or space inside of part holes, the opportunities are only limited by the sophistication of the nesting algorithm. For a much more extensive discussion of material savings opportunities check out these resources:
3. Machine Efficiency | Throughput, Productivity
Throughput can point to either machine efficiency (uptime, duty cycle) or production efficiency (product production cycle time, time-to-delivery, order response time). Either way in most instances faster is better, more is good up to the point in which there are diminishing returns from human errors, production mistakes, broken equipment. The sweet spot for optimal throughput is that point at which all resources (human and equipment) are functioning at a level of near capacity while ensuring minimal mistakes.
Advanced nesting programs achieves that throughput sweet spot. By reducing the programming and nesting time and error through automation, and relieving engineers and operators to manage the process, troubleshoot, and plan, the whole production cycle can and will move more smoothly. Programs can be on the floor well in advance of the next machine cycle to avoid any downtime. Programs can be automatically checked for accuracy - head collision avoidance, grain constraint, tabbing, leads, etc. - to avoid machine downtime due to errors.
4. Schedule Demand | Order Cohesion; Order Management
We talked to a manufacturer of emergency vehicles awhile back. Solid, manageable order cohesion was paramount to their process. Every order was 100% custom, and all of the parts for that order needed to stay together for the duration of the production cycle. That's a tall order if you're doing it without nesting program capable of handling it.
Nesting software handling order priorities. This is a not-often considered upside of advanced nesting program. A true, advanced nesting program will be a manufacturing-production extension of your ERP/MRP, or order management software. It will following your instructions, keep the orders together that need to be together, prioritize orders based on your priorities - arbitrary or date driven - and manage build-to-inventory needs. It can keep kits or assemblies together. It can and will figuratively speaking juggle all of the balls of production orders and keep the system moving without stress.
Nesting Programs as a Financial Resource
In conclusion, nesting programs are more than a tool to achieve part production. They should be part of your cost management strategy and among your financial resources to gain production efficiency. As we've discussed here, there are multiple ways to leverage a nesting program to bring down costs and improve productivity. And those benefits are compounded when brought to bear through one advanced nesting solution. How that plays out in your production environment is a conversation well worth having.
What is your nesting program doing for you? Are you achieving the full payoff you'd hoped from this tool? What would you like to gain, but aren't realizing? Comment to this blog post; let us know what's working and what isn't.
For more information on Optimation or to start a discussion, contact Optimation.
- How can a Small Company Benefit from "Big" Nesting Software?
There was a time – 10, 20 years ago – when only very large manufacturers like Caterpillar or Siemens could afford advanced nesting technology.
Conventional wisdom had it that because these manufacturers were large and had deep pockets only they could benefit from the advantages of automatic part programming and automatic nesting. Further, the thinking has been that the "big guys" could use this technology to support lean manufacturing, demand-pull, and other revolutionary, cost-cutting initiatives. Therefore, only they could benefit from tools that afforded less programming time, less material waste, better order cohesion, improved throughput and all of the gains gotten from advanced nesting.
Fast Forward to the 21st Century
Now, this isn’t the case. The best kept secret about advanced nesting software in the 21st Century is that it is not only viable for the small shops, but affordable. As with most technologies as innovation increases costs decline, and a product that may have seemed out of reach before is now very much accessible by all. We can point to a few changes in manufacturing, which have laid the foundation for the democratization of advanced nesting software.
CAD Programs Ubiquitous
Today, virtually every shop has its own design software. There is a pretty robust, full-featured CAD package in most manufacturing operations - regardless of the size of operation. As a result, several benefits to the manufacturer open up. 1) This common denominator among shops enables them to have digital part designs to export into a nesting program. 2) This development allows for standardization among part design conventions to make a nesting program function properly – importing many parts at one time, reading processes and manufacturing specifications (grain, rotation, etc.) automatically. 3) The use of a full-featured CAD program enables small manufacturers to separate the purchase of a CAD package from a nesting package and purchase the product that best suits their needs independently. 4) There is no need to buy a bundled CAD/CAM package simply to have the CAD utility or the CAM functionality. In fact, when using a CAD/CAM bundled package, the user inevitably runs into the problem of duplicate "golden" drawings. It's very easy to inadvertently create two copies of a CAD file that differ in the course of a busy day. All that has to happen is the engineer outputs manufacture-ready artwork from his CAD package and sends it to engineering. Then the machine operator learns of a last minute change needed or finds the artwork can't be cut as is. The operator makes the change on the floor in the CAD/CAM package and cuts the part. You now have two "golden" parts. Which one gets produced the next time?
Computing Power Ramping Up
Ten or more years ago, the thought of a small manufacturer having a computer powerful enough to run an advanced nesting program was unheard of. Only large, enterprise-sized companies could afford the Unix or Vax, room-filling computers that had the horsepower to drive a nesting program. We certainly don't have to look far to see evidence of the world having changed - dramatically. When our Smart Phones have more computing power than the first astronauts had at their disposal, we know we’ve seen a revolution in technology in our lifetime. Today, an everyday, off-the-shelf PC - even without the latest capabilities in speed and computing power - can easily handle the nesting algorithms in advanced nesting software. And at today's prices, most manufacturers have at least a few PCs in engineering and on the shop floor. Thus we have eliminated one more barrier to entry for nesting software for small shops.
CNC Machines Prevalent
It has been a generation (30 years) coming, but the conversion from NC to CNC among the fabrication equipment population is complete. Even the population of used equipment still in the marketplace, is driven by computer numeric controls. And where there is this almost universal demand for NC code to drive the equipment, there is a similar need to provide it through advanced part programming. Because manufacturers in small shops have to provide code, they have the golden opportunity to optimize that program through advanced nesting software. By taking one more step with scalable nesting software, the path to greater savings in material and programming is made clear.
Why Advanced Nesting Software?
Based on these arguments, it seems reasonable that there isn't a technology-based, or budget-based reason to prevent a small manufacturing shop to consider advanced nesting software. The next, and seemingly obvious question, would be "why?" Is advanced nesting software applicable in a small shop environment?
There are several reasons to consider this option.
1. Tame the Chaos
We hear from manufacturers all the time that everyday is an "adventure." The schedule is changing every 15 or 30 minutes. What was "hot" this morning is not as important as what is "hot" at noon. Priority customers, rework, keeping orders together, downstream priorities, and managing the every day flow of work creates a lot of chaos. Stress. Advanced nesting software can tame the chaos by managing the priorities and reworking the flow of parts and nests for the engineers when something happens to upset the schedule. Depending on the unique circumstances there are a number of advanced nesting tools that can be leveraged here including Batch and JIT Nesting to name just two. Imagine being able to respond to changes in production demand the very next machine cycle.
2. Control Order Priorities
Often deciding which parts are cut first can be a very subjective process. The machine operator may do the "easy" jobs first regardless of what's needed first. The customer who screams the loudest may get his job pushed in front of others - that may have a very legitimate claim to first priority. Orders may be segregated by job, product, customer or order just to keep the machine off-loading manageable with no attention paid to priority or nesting efficiency. Then there are those shops that just to keep it simple they handle orders on the first-in-first-out basis. Though very democratic, it may not reflect the true priorities of the orders. Wouldn't it be great of the nesting software could look at all of the orders and all of the priorities and due dates, and manage the creation and flow of nests accordingly? It can. Advanced nesting software can act as the order priority arbitrator and deliver the optimal result.
3. Reduce Programming Time
Unlike enterprise-sized manufacturers, small shops typically have finite manpower. More often than not, each person wears multiple hats. We've talked to CEOs that do the programming for example. The solution to stretching the manpower comes in a number of forms. It can mean long hours, and/or the use of nesting and programming short cuts. The programmer may create one nest for a set of parts, save it, and run it over and over. This saves time but sacrifices flexibility and possibly material efficiency. The programmer may program one part at a time and run it. This keeps the machine cutting, but at the cost of a lot of programming time and possibly material efficiency. These work-arounds work, but at what cost?
In those uniquely, resource-pressed small shop environments, advanced nesting and programming software can make a huge difference with tools that cut programming time by up to 90% and maintain or improve material efficiency and throughput.
4. Improve Material Efficiency
Small shops with no nesting software or a nesting-aiding interactive software probably have pretty good material efficiency. Why? Because a programmer if time is available can spend the time to drag and drop, twist and turn, move and shift each of the parts to create a nest. And with enough time, he is able to create a pretty efficient nest.
The challenge arises when there are more than a few parts to consider, and he has to look at keeping orders either separate or try to mix them intelligently. Then he needs to look at the sheet sizes and determine which would be best. Or should he use a remnant? But what about the "hot" order that showed up? Should he scrap the nests he just built to insert the new part, run it by itself, or add it to the next nest? None of which are great options. Even the most talented programmer would be stressed by all of the variables in place. Most solve the problem with work-arounds as mentioned above.
The alternative would be to put all of those variables - the parts, the due dates, the hot orders, the sheet size options, and more - into a "hopper" called advanced nesting software. Let it absorb the decision making "stress", and the programmer can relax. Believe it or not, it, too, will do a pretty good job - maybe even better - at material efficiency.
What have we discovered here today? We’ve learned that the barriers to obtaining advanced nesting software that were common a decade ago, simply are not the case today. Indeed, the equipment market is pulling small shops in the direction of using optimizing programs to drive their computer-literate equipment. Further, we have recounted four specific ways that small shops specifically and uniquely can benefit from advanced nesting software.
If you are a small shop and would like to discuss your circumstances and see if there is a fit with your needs, give us a call. We'd be glad to chat.
- How to Financially Justify a Nesting Software Purchase
- Technical Justification
- When Material Savings Alone Doesn't Justify the Purchase
One of nesting software’s the biggest benefits is material savings. Manufacturers can see improvements in material usage of 5-15%. That's huge! And that's one of the primary reasons material savings is called upon to help make the financial case for a nesting software purchase. There’s a clear line between use of nesting software and material saved in fabricating.
That said, what if you cut inexpensive material, where material savings isn't a big dollar figure? Or what if you don’t cut a large volume of material? Then can a case be made for the purchase of nesting software?
The answer is "yes." Let's talk about the other ways to make a case for nesting software that don't hinge on material savings.
Ask yourself, would it be worthwhile to either get more product out the door or shorten the amount of time it takes to get product out the door? If more product goes out the door, presumably revenues and profits increase. If this is of interest to you, you may have a case for nesting software.
Throughput: Streamlining the Process
Automatic nesting software can minimize or eliminate redundant or additional steps streamline the process, and increase throughput. If the machine operator changes out the turret fewer times, if there is less need for shearing, if there is fewer sheet sizes to manage, time and therefore money is saved. Further, because of the savings in process time, more can be accomplished in the same time and more product can go out the door increasing revenues and profits. When making a case for nesting software fortunately, this is measurable time. With some calculations it can be the basis for a cost justification for nesting software.
Throughput: Optimizing the Cut Path
Another method to achieve greater throughput is by looking at the cut path or tool path. This is the time and distance used by the cutting head or turret to cut or punch the entire sheet. Logically, the shorter the distance from start to finish the faster the cut time and the greater the throughput. Automatic nesting software can optimize for this benefit. Further, the time and distance can be measured and compared to existing practices - yet another tool for a cost justification. And as above, the faster the process, the more product that can be produced, which leads to greater revenues and profits.
For more windows into throughput savings visit this page.
Programming Time Savings
Sometimes a reduction of programming time can be used as justification for the nesting software purchase. Typically users can see a reduction of up to 90% of programming time with automatic nesting software.
There are three ways to find the cost savings here. 1) When engineers are at or exceeding capacity and either their time could be more cost-effectively used elsewhere then the better use of their time can be a basis for justification. 2) When engineers are unable to keep up with production demands and productivity and throughput suffer, then improving the speed of programming can and does increase throughput (capacity), which can be the basis for justification. And finally, 3) if the demand on programming is so great as to incur overtime costs, employing nesting software to expedite the process and reduce overtime can lead to direct, justifiable savings. The best way to quantify the time savings is to benchmark or test the programming time in an alternative software, then use those numbers to compare to the present situation. The difference is the cost justification.
For specifics on where to find programming savings opportunities check this out.
Just-in-Time and Other Nesting Strategies
Then there is the production flow discussion. If your facility is seeking to optimize its production using Lean Manufacturing, Six Sigma or any other sophisticated production flow techniques, nesting software is a near imperative. Beyond drawing a direct line to any savings, it is needed to put in place manufacturing strategies that require a faster programming speed, an ability to manage variety of due dates and priorities, and the ability to tightly integrate into upstream and downstream software such as an MRP/ERP system. The savings then become clearly apparent when the whole system – nesting software included – transforms the production facility and squeezes out waste everywhere.
In Conclusion -
As we have seen there are several ways to meet the needs of the decision makers when looking for a cost justification for a nesting software purchase. The answer may mean looking to one or more of these approaches, running the tests, doing the analysis and creating a cohesive, compelling argument. If that sounds daunting, that's okay, there are experts at Optimation, who travel this road every day and can help.
How about you?
Are you looking to build a case to justify nesting software? What's your approach?
If Optimation can help you build a justification, please contact us.
- Who Should be Involved in a Nesting Software Purchase
- How Long does it take to Research Nesting Software?
Don't you just hate it when you ask a seemingly straight-forward question, and you get a waffle-y answer like "it depends?" I think that's frustrating, too. But as we know life isn't always black and white. And as to the question, how long does it take to research nesting software, the answer really is, "it depends."
I will cut to the chase and give you a time frame of three to nine months up front. But in all fairness to manufacturers, the vendors, and the process, I need to flesh this answer out a bit to make it more constructive for everyone.
There are a number of factors that strongly influence the amount of time it takes to research and purchase nesting software. Let's take a look at a few, and you can use this as a checklist to plan accordingly when and if you should take on a nesting software research project.
1. Compelling Event - One of the biggest drivers is a compelling event. Something is happening in the future that is driving the research and decision timeline. Most commonly that is the purchase and arrival of a new CNC machine. If it is due in October, there really needs to be nesting software ready and waiting to drive it as soon as it is operational. It wouldn't be wise to start the research process any later than three months out from the delivery of a machine for reasons I'll explain. Other issues that would drive a timeline are a company merger, new facility, large new contract where more capacity is needed, or a new product line coming on line.
2. Bad Numbers - Another circumstance that tends to propel a timeline is the continuance or appearance of bad efficiency numbers. If the scrap rate is too high, the machine duty cycle is too long, the programming process is creating either overtime or bottlenecks, there may be a mandate to resolve the problem by the next quarter or the next fiscal year. These arbitrary dates hang as an endpoint for the research process.
Drivers of the research process notwithstanding, the actual process usually unfolds in a number of steps, which take time. The steps for each nesting software vendor under consideration are:
1. Initial Discussion
4. Discussions or Visits with Vendor Customers
6. Approval Process
There are a number of time consuming factors in the process. To what degree these impact the process, creates the variance between a three month and a nine month research project. The factors include -
1. Gathering and scheduling the financial and / or technical decision makers for demonstrations
2. Collecting parts for a benchmark
3. Gathering the financial and / or technical decision makers for customer visits or calls
4. Scheduling and visiting a customer
5. Reviewing the information presented in the demonstration
6. Reviewing the proposal with all of the decision makers
7. Getting final approval on the proposal
As you can see there are a number of steps in the process, and they can take time. This isn't meant as an admonition, but simply a reality check and checklist. It's a means to set real expectations on how long this process can take.
As I often say, most people, most companies are not in the business of shopping, and in this especially case shopping for nesting software. They have roles, responsibilities, and commitments that need to be addressed every day - then they have time to squeeze in the "nesting software" project. No matter how high of a priority it may be, it still needs to be managed within the context of a daily routine. And that means it takes time to work through each research step.
By planning accordingly and managing the project, the process can move very smoothly and quickly. The best projects start with clear expectations of what’s involved and how long it will take.
If you have questions or would like to discuss the process, contact Optimation.
- When Material Savings Alone Doesn't Justify the Purchase
- Financial Justification
- How to Research Nesting Solutions
- How to Shop for Sheet Metal Software
Whether you're in the market now or think buying sheet metal software may be a project in the future, it's helpful to have tools and techniques to make the process easier, more efficient and a productive use of your time.
Assuming you're not a professional buyer or in the corporate product acquisition department, you may not be used to identifying, evaluating, requisitioning, budgeting, and purchasing sheet metal software. It can be a daunting task for the uninitiated or the already busy.
Indeed, most manufacturing engineers, programmers, or even manufacturing management doesn't concern themselves with the software acquisition process on a day-to-day basis. Their focus is all about producing parts and products. And suffice to say, there isn't a lot of overlap in the steps and processes involved in purchasing software and producing a product. So there is often a fairly large, on-the-job learning curve to be had for anyone endeavoring to research and purchase sheet metal software.
The goal with today's discussion is to outline a few guideposts that will help facilitate the process and identify any potential challenges - before they become a problem.
What is Sheet Metal Software?
First a quick definition to make sure we're all on the same page. Sheet metal software is CAM or nesting software for 2D part fabrication. The software we're discussing automatically creates part programs, nests them on a flat stock material - most often sheet metal - finally, creates a tool path optimized for the equipment (punch, laser, router, Waterjet, plasma) that cuts the material.
What Makes Buying Sheet Metal Software Different?
Sheet metal software is a unique purchase - different than other manufacturing software packages, i.e. ERP, MRP, CAD - in that it can and will drive down overall manufacturing costs directly. Its value is more than a simple utility that enables a cutting process. The purchase can and is often justified based on a return on investment financially, and its capability technically to perform and optimize the required tasks.
How to Buy Sheet Metal Software
Because buying sheet metal software is a "different kind of purchase," with two trains of justification - technical and financial, we need to take the purchasing process down two different roads simultaneously.
Sheet Metal Software | Technical Justification
Often engineers and/or programmers are the first to see the ground level need for sheet metal software. They are looking for a tool that will save time, reduce errors, increase productivity, and all in all reduce their stress. Or there is a need to bring a new piece of equipment online, and sheet metal software is called for to drive the equipment.
Automatic sheet metal software typically meets these needs through automation of the CAD input, order management, CNC nesting, and tool path creation and output. All of these tools address the needs above. Additionally, there may be an interest in employing sheet metal nesting strategies - batch nesting, JIT nesting, Kit management and kit nesting. Again these strategies help create the basis for a technical justification.
Technical Justification | Shopping Tools Sheet Metal Software
As a project manager, you'll want to gain some assurances as to what degree the sheet metal software you're evaluating meets your needs. Here are a couple tools.
Demonstration or Trial Disks
Interesting thing about demo/trial CDs or executables, they do an excellent job of showing how the interface works. They give you a clear idea of what buttons to push, where to drag & drop, how to manipulate a nest, and what your day will be like interacting with the software - all day, every day. What they don't tell you is how effective the sheet metal software is at the things you're most interested in - saving time, reducing errors, increasing productivity, etc. A demo disk is like a simulator - it validates your personal experience, not your results.
A live demonstration - typically done over the Internet or in person - offers the opportunity to see and understand how effective the sheet metal software will be with your unique challenges. If your goal is batch nesting, you can see it operate in batch nesting mode, and clearly gauge the impact it will have on the programmer's time. If your goal is cutting the time it takes to bring parts from CAD to CAM, then you can see it operate in automatic mode - and clearly compare it to your present circumstances.
Benchmarks - a "test run" of sheet metal software using your parts, quantities, materials, guidelines - are a perfect opportunity to try before you buy. This is a tool, where you can get "proof of concept." That's a fancy term for seeing if the sheet metal software will do what you want it to do. Will it accommodate your needs - your unique parts, orders, timelines? You want to know, "Will it perform as I want and need it to perform with my parts, my machines, my due dates?" A benchmark will do that. Benchmarks are typically done for free, and repeatedly using in different manufacturing scenarios as needed. For example, you may want to know if this sheet metal software can do common cutting, and how it will impact your duty cycle, material efficiency, programming time, or even if common cutting is an option. A benchmark run with differing parameters can give you those comparative results.
Real World Experiences | Talking with Customers
Whether you are looking to meet the technical or financial justification needs in your research, there isn't a better tool than talking with real customers of the prospective sheet metal software company. They use the software, and they have no vested interest in whether you purchase or not. They are the best, authentic, independent and qualified review you'll get prior to purchase. Ask the sheet metal software company if they have customers either in your industry (which may pose a conflict of interest - company secrets), or better yet, someone running the same machines you're running or doing the operations, i.e. common cutting, they way you want.
Here's an easy list of questions to have at hand when you pick up the phone or make that trip on site.
1. What's the support like? (A demo and benchmark can't answer that for you. Only a customer can.)
2. What was the training like? How long did it take to learn it? (Again, only a customer knows this and can give you the answers objectively.)
3. What's your return on investment? How long did it take to pay for the software in savings?
4. What's been the impact on the production floor? Productivity? Throughput? Material Savings? Programming?
5. What were the challenges they were trying to overcome? How did it work out?
6. How does this compare to their previous process/software?
And there you have it, the straight scoop on best practices for researching, evaluating, and purchasing sheet metal software. This type of manufacturing tool is - and should be - an investment that pays dividends in time and materials regularly. A wise choice can make all the difference in what the future looks like for the sheet metal department. These tools are intended to enable a wise and clear choice.
Are you shopping now? How's the process going? Do you have any tips or suggestions from your experiences? Comment back, and share your ideas with the rest of the community.
For help and professional assistance in the purchasing process for sheet metal software, contact Optimation.
- How to Compare Nesting Software Using a Benchmark
When researching nesting software, most manufacturers turn to a benchmark as an objective, analytical tool to compare products. This article is a primer on benchmarks - what are they, how are they best used, and what every manufacturer should know going into a benchmark.
What is a Benchmark?
A benchmark is a "test run" of sheet metal software using your parts, quantities, materials, guidelines. It is a perfect opportunity to try out nesting software before you buy.
How is a Benchmark Done?
The manufacturer collects a real world, production-ready set of parts, order quantities, due dates, materials, and cutting or punching requirements. That is, he is assembles everything necessary to simulate the cutting of these parts. The manufacturer sends this data to the nesting software company to do a trial run or simulated run of these parts through their software. The results are returned to the manufacturer for comparison with their software and other nesting software products.
What Do You Look for in a Benchmark?
A benchmark is a tool, where you can get "proof of concept." That's a fancy term for seeing if the sheet metal software will do what you want it to do. Will it accommodate your unique needs - your parts, machines, orders, and timelines? How long does it take to create the nests? Tip: Ask to see the nest compile in real time. How fast do the nests run? What kind of material efficiency can the software provide? How does the software company achieve the material efficiency it demonstrates? Can it handle changes in part revisions, hot orders, new quantities? How does it do it? Can the software handle different manufacturing scenarios, i.e. with or without common edge cutting? What is the difference in efficiency? How automatic is the nesting process? How much manual intervention is needed? A benchmark will answer these questions.
How are Benchmark Results Presented?
Typically benchmark results are presented in an online meeting forum where you and any associates can see the nests, ask questions, and evaluate the results. Additionally, copies of the nests and summary data can be provided for further analysis or distribution internally.
What Do You Do with Benchmark Information?
Benchmark data, in addition to providing comparative information among nesting software providers, is ideal for use in a financial justification of the purchase. There's no better way of demonstrating financial justification or return on investment than a benchmark. Why? Benchmarks are excellent at contrasting the material use or time expenditures over your present approach. Here are a couple examples of how this is typically done.
These are just two ways to build a financial justification using benchmark data. There are as many approaches to this as there are manufacturing companies. The important thing to remember is that benchmarks are a valuable tool when compiling a justification for nesting software.
What Not to Do When Benchmarking
Creating a useful benchmark result is really a partnership between the manufacturer and the nesting software provider. It is truly a team effort to create a set of results that have meaning and relevance to the manufacturer. With this in mind here are a couple “dos” and “don’ts” to be cognizant of throughout the process.
Avoid the pitfalls that have befallen many project managers by having reliable, comparable data with which to evaluate your benchmark results. For a benchmark to be effective, useful, comparable, or valuable in a discussion of financial justification with your boss - and maybe his boss - it is imperative for the project manager to have an apples-to-apples comparison of nests. The most helpful is to have a set of parts for that is reflective of a slice of real production. (As mentioned earlier, this can be a day or a week's production - whatever is a representative variety of parts.) Then give the nesting software company these parts, due dates, materials, cutting/punching process, part constraints, trim requirements, etc. that you used in your slice of real production run. Now you can compare the results, and they will be meaningful.
How to Select the Right Parts for a Benchmark
Sometimes manufacturers pick "any old parts" for a benchmark because they are busy, doing their jobs and simply don't have the time and energy to give concerted thought to planning a benchmark. This is completely understandable, but not recommended. A few quick guidelines could keep this process still quick & easy but will deliver much more actionable results.
1. Don't pick sheet-sized parts, unless you're looking for a proof of concept for single part programming. There's no art or technology that would be tested to nest one, single, large part.
2. Don't pick lots of rectangles, unless all you have is rectangles. This is a baseline sheet metal function. Any simple nesting software can do rectangular nesting. Using rectangular parts exclusively won't discriminate among competitors.
3. Pick enough parts & orders to fill multiple sheets - using 10-20 sheets is a good place to start. This way you can tell how much time it took to program the parts and create the nest. This will also provide the sheet metal software the opportunity to work with many combinations of parts and quantities to demonstrate real material efficiency with advanced nesting algorithms.
4. Let the sheet metal software company know if there are particular constraints on certain parts, i.e. grain constraints, fixed leads, or long & skinny parts, which need to be across the slats. Let the nesting software company know about these rotation constraints, so you can see how it performs under real world conditions.
5. If at all possible, set aside 15 minutes to talk through the benchmark with the sheet metal company before they start on the benchmark. Let them know what you're hoping to achieve, what you're looking for, and where your current challenges are. Without a clear direction of where you're going, they will be hampered to give you the most relevant answer. Then let them come back with results to meet your needs.
Benchmarking is an excellent tool, free to project managers and provided by nesting software vendors, to provide the real world analysis needed to make an informed purchase decision. Don't be shy about asking for a benchmark, you have a right to know how any nesting product will perform with your parts.
How about you?
Have you had a benchmark performed? What kind of results did you get? What was the process like? Weigh in on the conversation.
If you're shopping for nesting software and would like to have a benchmark performed with Optimation software, just let us know.
- How to Benefit the Most from a Nesting Software Demo
It seems natural to start requesting demonstrations of nesting software when you begin your research for a nesting software package. The objective seems obvious. You want to know what the nesting software does and how it works. And one of the best ways to answer those questions is to see a demo.
Stop. Before you pick up the phone or fill out that online form to request a demo, there are several things you can do first to make the demo a productive use of your time. Trust me on this one. We've done a bazillion demos, and the manufacturers who were well prepared came away with clear action items, a clear idea of how it would benefit them, and a shorter, less-stressful acquistion timeline.
So here's the formula for watching nesting software demonstrations success.
1. Reserve space and time for the demo It's always hard to break away from the day-to-day routine to sit down for a demo, but you do yourself a disservice by not devoting a dedicated time and space for it. Reserve the conference room. Close your office door. Unplug your phone. You'll be able to focus and get the answers you need when the time is reserved. Also, let the software company know how much time you have for the demo. They should do everything they can to accommodate your schedule. Additionally, ask how long the demo should take so you can plan accordingly.
2. Online Demo? Check for internal access. Many demos these days are conducted online using services like GoToMeeting or WebEx, which means you need to have Internet access and an available long-distance phone line. Check in advance to make sure these tools are available for you in the space you've reserved for the demo. Some companies, especially military or defense related companies, have restrictions on Internet access, so it's always good to check.
3. Prepare your technical shopping list. When you're watching the demo, have a "shopping list" in mind or at hand. What are trying to evaluate when you see the software? Divide your shopping list in two - "gotta haves" and "wish list." Are you looking for certain features? This is important - what would those features do for you? Retain existing capabilities? Improve time or material use? Knowing why you want something is just as if not more important than knowing what you want. A good recommendation is to visit the software company's website before the demo and review what they say about their products and services. This should prompt ideas for good questions to ask.
4. Begin to plan your purchase justification strategy. Nesting software is unique in that it is not just a utility software that helps automate a process. It is a money saving, money generating tool. And as such its purchase can often be justified by the dollars saved in material and time saved in programming. Before you go to the boss to make your pitch - and before you sit down to see the demo - start thinking about how you're going to sell this to the decision makers. If you're at a loss on how to proceed, talk to the nesting software company. They work with manufacturers all the time to make these justifications. They will have good suggestions. If they don't, move on to the next software vendor. In the demo, ask about the features they show and how they can be used to justify the purchase. For example, does the vendor do common cutting? How can that help justify the purchase? (answer: material savings, programming savings, throughput increase)
5. Gather the team. Are you doing the first round of preliminary shopping and then you'll gather the rest of the team for a second look? Or should someone from design, estimating, IT, or the executive team sit in on this demo? If others are involved in the decision making process, ask them to bring their "shopping list" to the demo, and encourage them to ask questions.
6. Communicate in advance your process interests. Are you interested in seeing a punch, laser, router, or other demo? Or would you most like to see just a laser demo? Sharing your equipment list and your processing priorities (we do everything on the laser or we're getting a new punch) is most helpful in targeting the demo to your needs, and it will keep from wasting your time needlessly on features and functions that have no interest to you.
7. What's your fabrication process like? Have a quick conversation with the people doing the nesting software demo before the demo day. Let them know what your day-to-day process is like. Do you run in JIT mode or do you single part program? Is your order entry manual or are you "wired" to a sophisticated ERP system? What in that process is working; what would you like to change? That's another big point. Regardless of the new nesting approach you choose, there will be some changes - probably related to how you get parts in to the software, manage orders, create part programs and/or interface with the machine. Knowing what you like and don't like about your current process is a great place to start when you investigate the probable changes that come with new nesting software.
8. Come with an open mind. You may see new ways of doing something that you'd never considered before. It's best to keep an open mind and ask questions. Maybe this new process, technology, feature, tool could make a real difference in your operation.
9. Know what your next step is. When planning the investigation and possible purchase of nesting software, it's always a best practice to think a few steps in advance. So ask yourself, after the demo, then what? What happens next? If you like what you see, what's your next step in the process? (possible choices: another demo, a benchmark, a quote, or talking to customers) If you have questions after the demo, how do you want to proceed? (possible choices - internal meeting, follow up discussion with the vendor) And how fast do these things need to happen to be consistent with your timeline? Note: having a timeline - and sharing it with the vendor – is a good thing.
Demos are a perfect opportunity to do quality discovery work to make an informed decision about your purchase. It's the ideal time to ask lots of questions, explore new ideas, and learn about best practices and industry standards. There isn't a better learning time. The take away here is that that learning time is best taken advantage of when you do your homework in advance. If you set your own expectations in advance of what you want to see, do, and learn, you will know what a good demo looks like when you've gotten your answers, and have clear objectives after the fact, your shopping process will run very smoothly. I guarantee it.
And here's the bonus tip, if you have your plan in place as described above you'll be far less subject to the direction the software vendor may want to take you - which may not be in your plan. It's very easy to get caught up in the "bells and whistles," if you don't have a focus on what you're trying to achieve.
What's your experience?
Do you have a demonstration story to tell of a lesson learned or a great tip to pass along? Share your ideas.
For more guidance on a productive discovery process or to discuss a demonstration of Optimation software contact us.
- How to Shop for Sheet Metal Software
- How to Compare Nesting Solutions
- Understanding Nesting Strategies - An Overview
UNDERSTANDING NESTING STRATEGIES & TACTICS WHITE PAPER
Choosing the best method for your operation
A nesting strategy is an overall approach or direction to be taken with processes related to nesting parts. A nesting tactic is the short term actions taken to achieve the nesting strategy.
The intent of this paper is to describe and evaluate Fifth Generation nesting strategies and different tactics used to achieve them. The discussion falls into three categories roughly following the production process. They are:
- How nesting software see part shape
- How previous and current generation nesting software create nests
- How nesting software manage part flow
"HOW TO CLASSIFY A SHAPE" STRATEGIESIt seems intuitive that when you view a part shape, you see the shape as it is and can easily determine how the part best fits in the nest. But this isn't always the case when software views parts that are to be nested. Different nesting tactics approach what seems to be natural to the human eye in different ways with varying results.
TACTIC 1: RECTANGULAR NESTING - FIRST GENERATION NESTING
First Generation nesting software used Rectangular Nesting (see white paper describing the history and development of Nesting software.)
- What is it? Rectangular Nesting "draws" a rectangle around the part at the largest height and width. It treats the part geometry as the rectangle, not the real shape of the part when placing the part on a nest.
- Advantages. Rectangular Nesting is satisfactory if and when your parts are primarily rectangular in shape.
- Challenges. This process does not consider arcs, holes, or other non-rectangular variations in the part when nesting. Similarly, rectangular nesting does not create the opportunity for interlocking of parts. A common example of interlocking parts are two L-shaped parts, one rotated 180 degrees, locking together like puzzle pieces. Also, holes are not filled with standard rectangular nesting software.
TACTIC 2: HALF SHAPE (TRUE SHAPE) NESTING - SECOND GENERATION NESTING
- What is it? Half Shape Nesting identifies a portion of the actual shape of the part. It puts the shape in the lower left corner of the space available and identifies the minimum "X" and minimum "Y" coordinates where the next part can be placed. Often Half Shape nesting is called True Shape nesting because it uses the actual part boundary as it places the part. However, only half of the part shape is considered. Only the left side and bottom of the part is examined to determine how well it fits with adjacent parts. The top and right side are ignored until another part is placed next to it. In Half Shape nesting algorithms, the parts already placed on the nest remain stationary and only the newly inserted part is consider for placement and rotation.
- Advantages. Half Shape or True Shape Nesting is a more real-world approach than Rectangular Nesting, because it takes into consideration half of the actual shape of the part during placement. When the part shape is used, the nesting tool can find greater material savings advantages by rotating the part. It also opens up the possibility of greater nesting efficiency.
- Challenges. Half Shape or True Shape Nesting comes up short in its ability to make evaluations about the full shape of the part. Some questions it fails to answer include:
TACTIC 3: VISION EMULATION NESTING
- What is it? Vision Emulation is a feature of fifth generation nesting technology. Vision Emulation Nesting "sees" the actual full shape of the part and makes logical conclusions about it, just as a human looking at the part would. The process is modeled after human vision and decision making
- Advantages. Visual Emulation can automatically find occasions to reduce material waste by seeing parts to nest in the appropriate voids. It naturally reduces the nesting time by allowing the optimal placement to be seen - unlike previous generation nesting - by only trying reasonable shaped parts and orientations that are optimal.
"HOW TO CREATE THE NEST" STRATEGIESEach manufacturer has a unique set of production objectives. The nesting strategy used should be consistent with and supportive of the production objectives. For the purposes of this discussion a "nest" is considered one machine cycle processing one sheet of material.
TACTIC 1: MANUAL NESTING - FIRST GENERATION TECHNOLOGY
- What is it? Manual Nesting is the process of interacting with each nest by dragging and dropping each part geometry on the material. The user works with the individual parts - moving, replacing, and rotating - to achieve the optimal nest based on his priorities. The priorities could include material use, how much time he has, and any part priorities or due dates. All choices are left to the programmer to make.
- Advantages. Manual Nesting offers maximum programmer control over the layout of the nest. He has complete discretion over the part choice, part orientation, degree of material efficiency, and programming time.
- Challenges. Manual Nesting can be very time consuming and error prone. A nest may take hours to create and still lead to such issues as the possibility of laying parts on top of parts, creating problems with the tool path, no consideration for order cohesion, or material efficiency may not be optimal. For punching operations, tool setup optimization may be compromised. Further, there isn't a quality check mechanism to insure parts can be produced or errors don't exist in the nest.
TACTIC 2: FIRST FIT NESTING - SECOND GENERATION TECHNOLOGY
- What is it? First Fit Nesting Heuristics (algorithms) create an ordered list of parts. Most often the list is ordered from the largest part to the smallest part. The First Fit Nesting heuristic places the largest part in the list on the nest first, then the next largest and so forth. If the second largest part doesn't fit, the software moves down the list to the first part that will fit; hence the name "First Fit." Additionally, when considering the part for placement the nesting tool chooses from several pre-set rotation options (90°, 180°, 270°) to find the best fit. Best fit is defined as rotation that brings the center of gravity closest to the lower left corner (or other specified datum point).
- Advantages. The First Fit Nesting approach is more automated than manual nesting and can be less time consuming.
- Challenges. There are several limitations to the First Fit Nesting tactic. It is impossible to create a single list that will reflect all of the demands on the production schedule, i.e. due dates, hot parts, while maintaining a largest to smallest part order. Nesting mathematics is very complex. Since 50 parts can be nested in more than 10100 alternative ways, this single list is only one of the many possible nests and is extremely unlikely to be close to the optimal solution. Another challenge is the limited number of part rotation attempted. As an example, assume a rotation setting of 10 degrees. If a part must be rotated 92° and fit, the part would be rejected as not fitting in the space available. If the software is given a large number of rotations, the time to nest the parts can become impractical. In short first fit heuristics are blind and are not able to consider multiple requirements simultaneously. Despite these limitations, the first fit heuristic is used widely by a number of nest software suppliers. The reason that this 2nd generation heuristic is used so much is that it is easy to code and easy to understand. 3rd, 4th and 5th generation nesting technology is very complex and not published in the public domain. Many 2nd generation software suppliers offer multiple variations of the first fit method which they consider different nest algorithms.
TACTIC 3: MULTI-DIMENSIONAL COMBINATORIAL NESTING - THIRD, FORTH AND FIFTH GENERATION NESTING
"HOW TO MANAGE NESTING PRODUCTION" STRATEGIESReally, creating the nest is only part of the task of producing parts. Effectively managing the production schedule and the efficient flow of product is at the core of meeting manufacturing goals. First consider your production objectives - material efficiency, labor efficiency, part flow, throughput, flexibility, dynamic machine loading, setup costs, and overhead conservation - then look to these strategies to determine the best fit.
TACTIC 1: STATIC NESTING
- What is it? Static Nesting is the process of cutting multiple sheets of material with the same nest or part layout. The parts, the part quantities, the orientation of the parts, and the part layout all remain precisely the same on each sheet of metal cut with the static nest.
- Advantages. There are a couple reasons why a fabricator may turn to Static Nesting. First, if they are producing a very large volume of the same or same set of parts, such as the case with a kit or product assembly, it may be cost-efficient to spend the time to create one single nest (interactive or automatically) with the best possible material utilization, then cut the same nest repeatedly. Often this process will result in a custom size of material for each static nest. This tactic achieves material efficiency while minimizing programmer time in creating the nest. The part cost and cycle times could be determined from past experience and be the basis for future estimating. Often manufacturing cells are designed to eliminate setup and accomplish single kit flow.
- Challenges. Static nests are only useful when the nest can be repeated a large number of times. The biggest challenge with static nests is the lack of same part volume and that some high volume kits make poor nests. If a part design changes or a produced part needs to be re-created quickly, it is generally impractical or impossible to incorporate the new part into the static nest. Unless the new part is 100% geometrically the same or smaller than the part it replaces in the nest, a new static nest will need to be created. Hot parts are handled independently often at a high labor and material costs. Because of the normal changing demand on most shop floors, static nests are often only used for special kiting requirements.
TACTIC 2: AUTOMATIC SINGLE NEST CREATION
- What is it? Automatic Single Nest Creation is the process of creating nests automatically, one sheet layout at a time. Each nesting action is cued by the programmer. The nesting software creates the nest, assigns lead-ins, tooling, manages order priorities, and creates the tool paths automatically, without user intervention. When the automatic nesting process is complete, the programmer can review and/or interact with the nest if needed. The order information or pool of parts from which the automatic nests are created remains constant until it is updated.
- Advantages. This tactic affords the user the multiple advantages of automated nesting and the control of "final approval" or "final editing." Advantages include, but are not limited to: reduced programming time, optimal material efficiency, error checking, increased throughput, and overhead conservation. An intelligent nesting tool will be able to produce the nest in a matter of minutes, if not seconds, far faster than most machine cycle times, so keeping ahead of the production pace is typically not an issue.
- Challenges. The programmer is responsible for maintaining a fluid cue of nests for production. If problems arise in programming, a production bottleneck can be created. Often programmers work on a single shift while production can have two or three shifts. Production problems in shift two and three can cause delays and increased cost because the programmer is not available to correct the problem.
TACTIC 3: BATCH NESTING
- What is it? Automatic Batch Nesting creates multiple sheet layouts or nests with a wide variety of parts for a specific material in a single process. Unlike Static Nesting, it creates any number of nests required - some replicates, some unique. It looks at all part orders for a given time - a shift, day, week - then creates nests optimizing the material efficiency, order cohesion, and part due date.
- Advantages. Automatic Batch Nesting is designed to achieve maximum material efficiency through an automated nesting process using minimal human interaction or limited programmer time. An entire batch of nests, for example 2nd shift's production, can be created in a few minutes and ready for the machine operator to download and produce. If, after the batch is complete, changes in demand occur, such as a "hot part," the entire batch of nests can be discarded and re-run with automatic batch nesting affording far more flexibility than manual or static nesting. Production is able to see the demand that is in front of them and can better plan manpower.
- Challenges. Automatic Batch Nesting does not reflect changes in demand over time. If a batch nest run is created and downloaded to a machine with the intent of running the batch over an eight hour period, changes in the schedule are not able to impact the production results during that shift.
TACTIC 4: AUTOMATIC JUST IN TIME (JIT) NESTING
- What is it? Similar to Automatic Single Nest Creation, Just in Time creates one nest (sheet layout) at a time automatically without a programmer. The nest creation is triggered by the machine operator asking for the next nest. This allows the JIT nest to be created at the last possible time it is needed. The nest is then automatically generated without human interaction using the most recent order information. The next nest always reflects the current order demand. Hot parts and schedule changes are responded to with each machine cycle. Multiple machines are automatically load balanced; providing optimal use of your capacity on the most important items to be produced.
- Advantages. Automatic Just in Time Nesting has all of the advantages of Automatic Single Nest Creation - material efficiency, reduced programming time, increased throughput, and overhead conservation. The distinctive advantage JIT Nesting has is the user is ensured that all "hot parts" or any order demand changes will be reflected in the next nest. Additionally, workload is automatically balanced between machines by redirecting nests among machines as they become available. Inherent to JIT system is the optimal flexibility to react as production requirements change, machines become inoperable, or order requirements vary. Human nesting time is eliminated; freeing your most knowledgeable employees to support the JIT process. Material efficiency is greater because there are always more new orders waiting to be nested and there is no tail-off caused by running out of parts. Often unused material remnants can be completely eliminated. Kanban or other demand pull system are a perfect fit for JIT nesting. These real time production planning systems require maximum flexibility to an ever changing demand.
- Challenges. JIT nesting requires a very intelligent 5th generation nesting system. Simple single-dimensional 1st or 2nd generation nesting systems will fail to make the correct decisions in an rapidly changing production environment. JIT nesting is a new paradigm for most production employees. The new methods must be learned to gain the maximum advantage from the system. Support systems such as MRP/ERP, Kanban or Demand Pull must deliver reliable production plans or the JIT nests will produce the parts based upon an erroneous schedule.
ABOUT OPTIMATION®Optimation® delivers economic performance for fabricators through advanced nesting software. Optimation® develops and supports nesting and CNC part programming software for fabrication processes, which include punch, laser, plasma, Waterjet, router, and CNC knives. We cover the range from single-machine sites to sites with hundreds of machine tools with the highest possible automation. Our automated approach to manufacturing solutions dates back to our beginning more than three decades ago. It is our belief that routine - and even not so routine - nest technology fabrication can be best achieved through a rules-based system that reduces not only material waste but programming time and error and keeps the manufacturer in control.
- What is Dynamic Nesting?
There are a lot of terms tossed around to describe types of nesting. "Dynamic" is one of those terms, and, unfortunately, often its meaning gets lots in translation.
What is Nesting?
First, let's be clear about what nesting is and is not. Nesting in fabrication describes the laying out of multiple 2D or 1D-parts in a defined space to be cut from flat stock (sheet metal, composite material, etc.). Typically, the nesting goals include material efficiency and/or response time / throughput. Additionally, the nesting process implies the creation of the part program suitable for manufacturing and a tool path to direct the cutting by CNC machine.
Not – Single Part Programming
What nesting doesn't include is "single part programming." When single part programming, the programmer is placing one - often very large - part on a single sheet of material. The reason single part programming isn't under the umbrella of nesting is because of the single part nature of the program. There aren't multiple parts to arrange in an optimal manner to create a "nest."
Dynamic nesting points to a fluid or varied part selection as to be distinguished from "static." Dynamic and can mean one or both of two things. First, it can point to the variety and complexity of the orders. There can be many, many different orders ranging in due date, size, number of parts, size of parts and even materials. It also reflects the rapidity of change. Orders can and often do come in with great frequency.creating a very dynamic environment. The other aspect of dynamic nesting points to the variety and complexity of the parts. Dynamic nesting manages many, many different part sizes, shapes, materials, cutting requirements, cutting constraints, tooling, and much more.
Dynamic nesting seeks to manage a real world environment of constant and rapid change sent down from scheduling and engineering/design.
Dynamic nesting realizes there is only one constant "change." And it is flexible enough to adapt to that environment and still control material and programming costs.
For more on advanced nesting check out these two reports:
For more on Dynamic Nesting visit this blog post – Dynamic Nesting v. Static Nesting | 6 Comparison Points
- What Makes Dynamic Nesting "Dynamic?"
Dynamic Nesting is one of those ubiquitous terms that often has different meanings depending on who you are talking to and what their previous experiences have been. The term “dynamic” can point to three different attributes of the nesting process – 1) the shape and variety of parts, 2) the management of due dates and priorities, and/or 3) the mixing of orders.
Mixed Part Shapes
Most commonly, dynamic nesting is distinguished from static nesting by the ability to nest many parts of different sizes and shapes. There may be ten, twenty, or fifty parts on a sheet or nest, but there may be up to an equal number of different parts. “Dynamic” in this case means the combining of large and small, round, rectangle, obround, and any other shaped part in one sheet of material to achieve an optimum fit. The user in this scenario is focusing on optimizing material efficiency. For more on mixing parts and how it differs from static nesting, check out this blog post.
Mixed Due Dates and Priorities
Often, however, dynamic nesting means the ability to combine part orders with different due dates or priorities. The user may employ the nesting engine to first fill the nest will everything due today and any “hot orders.” Then, if there is space to look for additional parts with less pressing due dates to fill in the voids and increase the material efficiency. The dynamic nesting engine can be calibrated to meet any combination of urgency and/or efficiency the user desires. The user in this case is focusing on optimally managing change and chaos in the production flow and material efficiency.
Finally, dynamic nesting can mean mixing orders, customers, kits, or any other combination of parts that are typically segregated in a static environment. The orders (or other unit identification) are mixed most often to improve material efficiency. However, within this strategy, the orders (or other unit identification) can still be identified and managed for optimal order cohesion to make common sense management of off loading and downstream processing. The user here seeks to optimize order cohesion and material efficiency by mixing orders in a well-managed manner. For more on mixing orders, visit this blog post.
Optimation gives you the opportunity to do any or all of these approaches to dynamic nesting to achieve your set of priorities of order cohesion, material efficiency, throughput, programming time, and response to change.
How about you?
Do you do dynamic nesting? What is dynamic about your nesting?
If you’d like to know more about dynamic nesting, let us know. We welcome the conversation. Contact us today.
- Dynamic Nesting v. Static Nesting | 6 Points of Comparison
What's the difference between dynamic nesting and static nesting?
They are two nesting strategies frequently used in 2D or sheet metal fabrication. Both strategies speak to the means and method by which the parts are ordered, arranged or laid out and produced on the laser, punch, plasma, router or other fabrication equipment.
Although they serve the same need of nesting, the differences between the two approaches are striking.
So there you have it, a contrast between the nature and process of static and dynamic nesting and their relative applications. We often find that static nesting is a method born of necessity to cut the programming time and still have a respectable material yield. It is only when inventory spirals out of control, or scrap is too high, or changes comes too fast that this work-around becomes unfeasible. Enter automation with dynamic nesting software.
How about you?
What is your nesting strategy? Do you use static or dynamic nesting or a combination? What led you to this choice?
If there is an interest in automation through dynamic nesting, contact Optimation. We can help think through the process and the possibilities with you.
- Nesting Algorithm Differences You Need to Know
When researching nesting software, it is very common for project managers to see all nesting software - even dynamic nesting - as the same. However, the nesting software marketplace reality is very different.
As you might expect with all software, nesting software has evolved tremendously over the last thirty years. What you need to know is that it has gone through five generations of evolution, and all five generations are still on the market today. What you need to know is how to identify each generation, what each generation does and doesn’t do for you, and how each would solve your nesting needs. It is the only way to make an informed, wise purchasing decision.
The generations are distinguished by the approach to nesting - how the algorithm addresses each part, optimizes for efficencies, and ultimately creates the nest.
First Generation - Rectangular Nesting
Second Generation - First Fit Nesting
What is it? First Fit Nesting Heuristics (algorithms) create an ordered list of parts. Most often the list is ordered from the largest part to the smallest part. The First Fit Nesting heuristic places the largest part in the list on the nest first, then the next largest and so forth. If the second largest part doesn’t fit, the software moves down the list to the first part that will fit; hence the name "First Fit." Additionally, when considering the part for placement the nesting tool chooses from several pre-set rotation options (90°, 180°, 270°) to find the best fit. Best fit is defined as rotation that brings the center of gravity closest to the lower left corner (or other specified datum point).
Challenges. There are several limitations to the First Fit Nesting tactic. It is impossible to create a single list that will reflect all of the demands on the production schedule, i.e. due dates, hot parts, while maintaining a largest to smallest part order. Nesting mathematics is very complex. Since 50 parts can be nested in more than 10100 alternative ways, this single list is only one of the many possible nests and is extremely unlikely to be close to the optimal solution.
Another challenge is the limited number of part rotation attempted. As an example, assume a rotation setting of 10 degree increments - 10, 20, 30, 40, etc. - and can only be rotated in those increments. If a part must be rotated 92° to fit, the part would be rejected as not fitting in the space available. If the software is given a large number of rotations, the time to nest the parts can become impractical. In short first fit heuristics are blind and are not able to consider multiple requirements simultaneously.
Despite these limitations, the first fit heuristic is used widely by a number of nest software suppliers. The reason that this second generation heuristic is used so much is that it is easy to code and easy to understand. Third, fourth and fifth generation nesting technology is very complex. Many second generation software suppliers offer multiple variations of the first fit method, which they consider as different nest algorithms. The user can run the parts through one algorithm, see the results. Then the user can run it through the second algorithm, see the results, and compare it to the first algorithm, and so on. It can be pretty laborious.
Third Generation - Half Shape (True Shape) Nesting
What is it? Half Shape Nesting identifies a portion of the actual shape of the part. It puts the shape in the lower left corner of the space available and identifies the minimum "X" and minimum "Y" coordinates where the next part can be placed. Often Half Shape nesting is called True Shape nesting because it uses the actual part boundary as it places the part. However, only half of the part shape is considered. Only the left side and bottom of the part is examined to determine how well it fits with adjacent parts. The top and right side are ignored until another part is placed next to it. In Half Shape Nesting algorithms, the parts already placed on the nest remain stationary and only the newly inserted part is considered for placement and rotation.
Challenges. Half Shape or True Shape Nesting comes up short in its ability to make evaluations about the full shape of the part. Some questions it fails to answer include: Is the next part the best part to select for this location? What is the best orientation for a group of parts? Half of the part may fit well with existing parts on the nest at some odd orientation, but that may cause subsequent parts to cascade into a random inefficient
Fourth Generation - Multi-Dimensional Combinatorial Nesting
What is it? Multi-Dimensional Combinatorial Nesting is another automatic nesting technique. The software uses mathematical fathoming to eliminate alternatives that do not need to be considered. See the Flash presentation for a full explanation of fathoming. The nesting software automatically and intelligently considers only those part combinations (nests) that take into consideration machine efficiency, schedule demand, order completion, material efficiency and many more real world requirements. Part layout solutions that are outside of the optimal solution set are simply not considered. In this approach, the production priorities are part of the expert knowledge base in the nesting software enabling it to make intelligent decisions. Due dates, hot parts, machine efficiency, material cost, part attributes and more are evaluated then optimized into a nest or series of nests that the optimal solution to the user's requirements.
Advantages. This method significantly reduces programming time and retains the best possible results for all considered factors - schedule, material, order completion, etc. Benchmarks show 8% to 16% higher material utilization over other methods.
Challenges. While the technology can be simplified and used in any environment, the expert system technology can best be leveraged by fully integrating the system with other manufacturing systems such as ERP/MRP, CAD and other common manufacturing tools. Training and a good support system is necessary to gain the maximum benefit from the technology.
Fifth Generation - Vision Emulation
What is it? Vision Emulation is a feature of fifth generation nesting technology. Vision Emulation Nesting "sees" the actual full shape of the part and makes logical conclusions about it, just as a human looking at the part would. The process is modeled after human vision and decision making.
Vision Emulation looks at the full shape of the part and the space available on the nest, then determines if there is an optimal fit.
Vision Emulation also evaluates the part to determine if and how much rotation is needed to provide an optimal fit. The actual part shape and the shape of adjacent parts is used to determine the optimal orientation. Multiple parts may be viewed on one time. A part could be rotated 123.456 degrees to achieve an optimal fit. This process eliminates the time consuming trial and error process of rotating the part in hundreds of small increments to check for fit. To understand the advancement that Vision Emulation provides, imagine putting a puzzle together in the dark. Without the ability to see the puzzle piece, you would have to try many orientations to determine if the part fits. Vision Emulation is like turning on the lights.
Contact Optimation for a discussion of the best nesting algorithm for you.
- Automatic Nesting and Automated Nesting - Smart Shoppers Know the Difference
To the uninitiated manufacturing professional the two terms "automatic" and "automated" as they apply to nesting and nesting software can whiz by undifferentiated in a conversation. That's perfectly understandable because our everyday experiences afford us no reason to assume there is much difference between the two terms.
Ah, but it is in that distinction where an important mistake is made when it comes to looking at nesting processes and nesting software. There is a difference, indeed, a big difference between the two terms as they are applied to the nesting process. The big difference boils down to the amount of human interaction, human time, human decision making, human-driven errors, and human effort you can expect from each process.
As we know there are many, many steps in the process of creating a nest and CNC code to drive a laser, punch press, router, etc. Those steps include – but are not limited to – importing and cleaning the geometry, identifying the order quantity and material, laying out the parts based on some formula or set of priorities, and, finally, creating the machine-specific tool path.
Automatic and automated nesting approach these processes from two completely different perspectives.
Let me explain.
Automated nesting begins with the manual nesting process and looks to create short cuts to make the manual process easier, faster. Automated nesting looks at each of the discrete steps (listed above) and applies macro-like software tools to speed up the human interaction. There are still copious amounts of human interaction, but it is - or should be - faster than doing the process manually.
Here's an example. Automated nesting will give you the tools to clean geometry (remove redundant lines, connect entities, eliminate irrelevant points) yourself. You have the graphical tools on the screen to make part changes to enable manufacturing. Along the same lines, automated nesting gives you the ability to interact with the part to set a grain constraint or identify bend lines post-design, pre-manufacture.
The nesting the parts is at the heart of the nesting process. Automated nesting will create a nest with the philosophy and tools that the engineer or programmer will come in after the fact and edit the nest. Automated nesting doesn't seek to create the optimal nest independently, just a nest sufficient to act as a starting place for editing. What do we mean by "editing?" You'll hear of editing terms like "bump" and "drag." This is the manual process of squeezing, rotating, deleting, adding, re-arranging parts to improve the nest that the automated nesting software created.
As may be coming evident, the automated software acts as a lever to amplify the human strength, which in this case is the time and mental energy spent to create the nest, part programs and tool path (cnc code). It still takes human involvement, human interaction and opens the possibilities to human-generated errors, but it is faster than creating a nest manually.
Automatic Nesting, in the truest sense of the term, stems from a different philosophy. Its goal is not to amplify human daily interaction, but to minimize or eliminate it using intelligent, logic and rules-driven software settings pre-set and defined by the human engineers. Automatic nesting creates an intelligent decision-making foundation based on human intelligence during a one-time set up. Then it acts as the human engineer or programmer would, making decisions as the human would, creating nests as the human would - all without the daily efforts and tedium of human interaction. The human (engineer) retains total control of the nesting process by creating the automatic environment to his/her liking, then delegates to the software to act on his/her directions.
What does automatic nesting look like?
Imagine bringing in those same unedited, not-ready-for-manufacturing parts as mentioned above into the CAM software. Automatic nesting software knows the tolerances you prefer for connected entities, redundant lines, etc., because you've told it them - once. Automatic nesting software then looks at each part as it is libraried and cleans the part itself. Only when and if a part comes through that exceeds your tolerances, does it raise a flag and the human engineer needs to review the part. Indeed, automatic nesting can be about bringing in lots of unique parts at one time as in a batch. Simply import the files as you would any other program where there is an import function, but the software - behind the scenes - clears the parts ready-for-manufacture.
Automatic nesting, when it comes to the actual nesting process, is so much more powerful than an automated process. You've told the automatic nesting software your preferences for how you want your nest created. (It's kind of like asking for "salad dressing on the side" at a restaurant.) You've told it when, where and how you would like common cutting done. If there are parts that fall between the slats, you've told it to look for them and orient them automatically based on your size preferences. It knows how to create a tool path that avoids loose parts. It knows how to create optimal nests using your part priorities (due dates or arbitrary settings), your needs for order cohesion, your material efficiency minimums, your trim allotments, your tooling, and on and on. Then given your “rules” it performs the nest creation process quickly and efficiently.
Automatic nesting is a tool that you program - once – to act like you. To nest like you would nest. To create part programs like you would like to do. To meet manufacturing requirements (scrap rate, throughput, programming time) that you are required to meet. Then you push the "start button." And walk away. No editing, no cleaning, no massaging, no re-running, no rework. It's a process that you can trust because you set it up to think and act like you would do.if you wanted to manually do the nesting.
So, in sum, there is a notable difference between automated and automatic nesting. It's a little known difference, but one that without understanding can create unexpected results down the road.
To ask about automatic nesting and the difference it can make in your process, contact us.
Meanwhile, let us know what you think. What nesting process – automated or automatic or something else – are you using ? How's it working for you?
- JIT Nesting Software
It’s possible to do this. Really. Allow me to introduce you to "Just-in-Time Nesting."
What's Just-in-Time Nesting?
JIT Nesting Advantages
Eight Best Practices for Implementing the JIT Nesting Strategy
How Does Just-in-Time Nesting Work?
It's that simple. It's that automatic. It's done in less than one machine cycle.
For a broader discussion of nesting strategies read Understanding Nesting Strategies and Tactics.
- All About Kit Nesting
Some manufacturers - maybe you - build products out of component parts. Those completed products are kits or assemblies or units, depending on the term you use. Some parts are sheet or plate metal; some are not. Some parts involve extensive post-fabrication work (bending, forming, painting); some not. But the one thing all kit parts have in common is that they belong together. Kits are designed as a unit and need to be programmed together, nested together, cut or punched together, assembled together, and ultimately delivered together, which creates a rather difficult production challenge.
How do you keep the assembly parts together in a cohesive unit, while reducing the programming time, managing the material yield, and not slowing down machine productivity? There are sheet metal software best practices to help. Often times one or two of these goals are sacrificed to achieve another goal in what is seen as a zero-sum game.
It doesn't have to be that way. There are tools and practices that can help achieve all of these goals in concert and without sacrificing one good for another. Let's look at some of the day-to-day challenges kits present and some solutions to the problems.
Four Best Nesting Practices to Kit Building Challenges
Challenge – Time Consuming – Kits take an inordinate amount of time to order (taking the bill of materials and communicating it to production). Each part geometry needs to be ordered separately - maybe in multiples, but separate from other geometries. There may be dozens or even hundreds of parts to each kit. That's a lot of ordering! And placing the order to have them manufactured, pulled from inventory, ordered from a supplier is a very complicated, time-consuming task.
Best Practice Order your kits as whole units. Imagine your orders as files with subdirectories reflecting each piece part with associated quantities needed for the completion of one unit. Your ordering utility within your CNC sheet metal software should be able to explode those aggregate subdirectories into individual piece part orders and multiply them against the total quantity needed. Doing this can automatically produces parts for nests accurately reflecting your production due dates and timelines.
Challenge – Error Prone - With the amount of detail involved in ordering the individual piece-parts for the nest, the opportunity for human error is enormous. It is easy enough to order the wrong part, the wrong quantity of parts - too many or too few, ordering them with the wrong due date to sync up with downstream processes, or missing a piece-part order altogether. Any one of these simple mistakes can amount to giant headaches on the shop floor. An ordering mistake can mean confusion on the floor, delays downstream, mistakes downstream, and worst of all an unsatisfied customer due to inaccuracies or delays.
Best Practice Minimize the human interaction in the process. Eliminate the piece-part order keying for each kit for production. Assuming the orders are already in electronic form - an Excel worksheet would be sufficient - automatic nesting software can pick up the order number, part number, quantity, designated material, and any other assigned information without human interaction or human error and bring it into the nesting software quickly and painlessly.
Challenge – Tedious CNC Programming Work - The plain truth about kits is that they are a programming pain. No programmer looks forward to working with kits because it is slow, detailed work that in reality takes a lot of uninterrupted concentration, but not a lot of intelligence to perform. The degree of repetition is high simply because the same grouping of parts needs to be ordered over and over and over again. It's not fun work.
Best Practice Step away from the commitment to routine, dull work and lean toward higher value activities. Where programmers and engineers really make a difference is in their ability to assess processes and look for more production-improving tools and troubleshooting - handling the exceptions to the process. Is there something more productive, engaging, and frankly, interesting you could be doing? Lean into to that and turn over the mundane to an automation tool – automatic sheet metal software.
Challenge – Disaggregated Kits - The whole idea behind producing a kit is to build a kit, not a mish-mash of incomplete sets of parts. And that's only possible of all the parts for the kit can be moved through the production process together. The right parts hit the laser, the punch, the paint room, and the welding cell at the right time and in the right order. With all of the parts coming together as if by magic to be assembled. Timing each process and making it as error-free as possible are the secrets to keeping a kit together. When the component piece-parts of the kit are disaggregated, the whole process can quickly come off the rails. And the shop floor turns in to chaos. Then the time involved in assembling the kit and the opportunity for even more errors go up exponentially.
Best Practice Just-in-Time (JIT) Kit Nesting. JIT Kit Nesting is a process by which an entire kit is ordered for nesting, one kit at a time or "Just in Time." All of the piece-parts of an assembly or kit are ordered at one time, simultaneously, and are processed in the nesting algorithm as one, cohesive unit. The automatic sheet metal software keeps parts together in the nesting process while material efficiency is optimized. As the parts and part quantities dwindle for the first kit, the piece-parts for the second kit are integrated in the sheet metal layouts. Again, keeping the kits separate, yet optimizing the material efficiency and machine up time.
There is no getting around the tasks inherent in ordering and nesting kits. The piece-parts need to be ordered, errors need to be eliminated, kits need to be held together, material must be optimized, and then there is the ever-present downward pressure on programming time. The good news is that there are best practices and automatic nesting software that can make a better - even positive – experience out of the nesting of kits.
How are you managing kits? Have you created workarounds to make it more tenable? What's your story? Let us know.
- Single Part Programming Pros & Cons
We often hear from manufacturers that they are doing single part programming. Some do it by design. Some do it by default. Either way it is a process that dramatically impacts how your fabrication operation works. Therefore, it merits a discussion to better understand what it is and how it strongly influences throughput and material efficiency outcomes.
What is single part programming?
Single part programming for our purposes is the laying out of one - often large - part geometry on a single sheet of metal, then creating a tool path program to be sent to the 2D cutting equipment, i.e. laser, punch. Quite frequently this process is preceded by a shearing operation where a sheet is cut to the exterior part dimensions of the part. The material is "sheared to size." Then the blank part is punched or cut to fit the specifications based on the single part program created previously.
To Nest or Single Part Program
The question of whether to single part program or nest really comes down to priorities - your, the department's, or the company's – priorities. It is the age old question of throughput versus material. Which is more important?
Does the time expense spent programming each part individually outweigh the cost of throughput (speed of production) or material usage that may be improved through nesting? Is time better spent in programming and/or shearing? Does getting more products out the door mean enough increased revenue to justify the programming time?
Or is the time better spent in achieving improved material efficiency? Greater material savings outweighs the cost of the programming time.
Let's look at the pros and cons of single part programming in a little more detail.
The Upside of Single Part Programming
- The part is so large as to be either the size of a sheet or greater than the sheet size. There's no need for a nest because no parts can fit on the sheet with it.
- Cutting the exterior dimensions of a large part would be more machine-time consuming on a CNC punch or laser than a shear. If this is true, and there are no parts to nest with a large part, then shearing to size would maintain throughput.
The Downside of Single Part Programming
1. When there are enough small parts – identical parts or different – to be nested with a large part better material utilization can be achieved.
2. When there is a large void (window, cut out) in a large part that can serve as a place for smaller parts to be nesting material waste can be minimized.
3. When there is a sizeable remnant along the trim strip or clamp edge that can be used for nested, smaller parts more efficient nesting can be employed.
1. When the shearing operation impedes throughput and the process can be better streamlined by cutting/punching the part in its entirety time can be saved.
2. When the programming time necessary to create individual part programs leads to machine downtime or other production disruptions downstream processes can be more efficient.
What if material & throughput are both important?
Here's the real challenge. Sometimes, both material and throughput are important. Usually most manufacturers don't face a clear either/or decision. Often there are conflicting priorities in the same shop. The programmers want less time-consuming work, and management has a keen eye on the scrap rate. Or some parts lend themselves to single part programming and others do not.
The Automatic, Dynamic Solution
The solution when you want to achieve both material efficiency and throughput is to have a CAM system that is flexible enough to meet both goals - at the same time. You need a CAM software that can minimize or eliminate the need for single part programming, and be able to do it where there is no other option. A nesting software package should be able to cut programming time to a minimum through automation and eliminate any throughput issues. This nesting software should also be able to identify opportunities to maximize material yield.
It's a tall order. We recommend looking to Optimation nesting software if you are one of those manufacturers that need to watch waste and control programming time and keep throughput up.or any combination thereof.
What about you?
Are you doing single part programming? How’s it working for you? What works? What doesn’t? Join the conversation.
- Understanding Nesting Strategies - An Overview