Monthly Archives: October 2012

Does Your Cut Path Look Like This?

Optimizing Tool Path for CNC Lasers

Optimizing Tool Path for CNC Lasers

Is your machine cycle time satisfactory?  Are you crashing – or risking crashes – from freed parts?  Does your cut path look like a swirling mess?

If any of these questions ring a bell, you may be experiencing loss of throughput or productivity.  It may be simply taking laser too long to cut a sheet and get the work done in the allotted time.

For some shops, their critical need is not to save material, or keep orders together, but to get the product out fast.  Turn around time can be hours for shops to take an order, process it, and have it at the customer’s door.  A crazy cut path can be a real show stoppers.  .

If machine throughput or productivity is important, there is a solution.  Crazy tool paths, head crashes, or loose parts don’t have to be the norm.

We’ll look at a couple tools available with laser nesting software.

Tool Path Optimization – The first place to start when looking for machine cycle time improvement is the tool path.  Does the head or turret proceed in a logical manner from one end of the sheet to the other minimizing travel time or does it look like the picture above?  Each few seconds of extraneous time spent adds up and over a sheet or a run the time can be prohibitive.

A nesting software with tool path optimization looks for the best tool path when cutting from one end to another.  It seeks to minimize rapids (non-cut travel) and find the shortest path from one completed path to the next pierce or edge-start.  It avoids crisscrossing already cut paths to inadvertently release parts causing tip-ups and head crashes.

Collision Avoidance – Does the path avoid crossing over previously cut paths, holes (where the head can drop in and crash), or the edge of the sheet? If so, that’s a problem.  Collision Avoidance logic directs the cut path away from precarious situations that could cause harm to the machine, the material or the operator.  And, not insignificantly, it cuts the tool path and cut time.

Common Edge CuttingCommon edge cutting with overcut is part of a tool path that cuts two part edges with like entities or arcs at the same time with on head pass.  The simultaneous cutting of part edges not only reduces waste, but it cuts down on the machine cycle time by eliminating unnecessary cut paths.

By the way, the overcut is significant because it directs the laser head to cut beyond the part edge on the first side of the part.  Why? Because when the part’s tool path is complete – the head finishes the enclosed path – the head doesn’t meet a previously cut part, risking a tip up or head crash.

For more information about optimizing a tool path contact Optimation.

 

 

Nesting Software Increases Productivity 320 Fold

Vac-U-Max Productivity U-Turn

Vac-U-Max Productivity U-Turn

We talk to manufacturers every day.  Each story is unique.  Some are in need of material savings.  Some are struggling with the slow task of programming.  Some want to better manage orders.  Finally, some are looking for a better way to connect engineering design, scheduling, and the shop floor.

Vac-U-Max from Bellevelle, NJ, was hampered by the manual nature of their programming and nesting operation.  Programming created a massive shop bottleneck.  It  took multiple hours per day and held up the laser operation.  The laser, not to mention all downstream operations, was “impatiently” waiting on programs every day.

Not good.

Fortunately, Vac-U-Max reached out to Optimation for help.  The result was a dramatic turn-around in productivity.  The laser didn’t need to wait – it could be running not 4 hours per day, but 10 hours per day as more work was brought in and the fabrication operation scaled up.  Vac-U-Max slashed the time from design to nest from  a ratio of 4 hours of programming to 4 hours of cutting to 15 minutes of programming for 20 hours of cutting.  A 320-fold increase.  The positive results were very apparent from “Day 1.”

Excellent!

Read more about the turn-around success story the partnership between Vac-U-Max and Optimation create here.

 

Eight Ways to Reduce Waste with Automatic Punch Nesting Software

Optimizing Sheet Metal Sizes and Inventory

Optimizing Sheet Metal Sizes and Inventory

The right automatic nesting and part programming software can cut material waste by 3-5% conservatively.  Many see it as a tool of programming efficiency and throughput, not realizing it can achieve bottom line savings through material efficiency, too.  In this paper we’ll look at eight ways advancements in nesting technology that enable a user to cut scrap, eliminate waste and increase the dollars that hit the bottom line.

1.    Common Punching

Common edge cutting is often practiced in contour cutting; however, can be done – automatically – in turret operations or with punch nesting software.  Common edge punching aligns like-profiled parts next to each other in the nesting process.  Then tools the adjacent part edges in such a manner that one tool hit punches two part edges simultaneously.  This not only damps down the press duty cycle by eliminating one sequence of hits, but it eliminates the web between parts – saving a significant amount of material.  For more information and illustrations visit here.

2.     Nesting Beneath the Clamps

In a turret environment the material is held to the bed with clamps to hold the material securely when the sheet is repositioned to prevent parts from freeing or tipping prematurely.  This security comes at the cost of material efficiency because as much as 3 – 4 inches along the length of the sheet is reserved for a trim strip or clamp zone.  Automatic nesting beneath the clamps retrieves a large part of that trim strip by placing parts in the trim zone, then strategically planning hits in and around the clamp holds before and after they are repositioned.  Again, saving thousands of pounds of material from the scrap bin.  For more information visit here.

3.       180 degree pairs

How parts are oriented on a sheet can make a huge difference in material efficiency.  That may be intuitive.  What may not be so obvious are the bonus savings opportunities when like parts are paired together to take advantage of their concave profiles to either insert other parts in the recesses of two parts or put the two parts together so they can self-maximize their efficencies.  Imagine two “L” shaped parts paired inversely to create a “hole” inside of the two shapes.  Or take the circumstance of two “C” shaped parts paired facing each other and offset to maximize each void.  The difference with an intelligent nesting algorithm is finding and using these opportunities to save material.

4.       Parts in Parts

Not unlike the creative nesting in 180 degree pairs, parts in parts takes advantage of holes inherent in the design of a part.  Automatic nesting seeks out and identifies parts that would be good candidates for another part to be placed within.  For example, if a part is shaped like a window with a large void in the middle, one or more parts can easily be placed inside the window to optimize efficiency.  Frequently, this tool nets a greater than 100% rectangular material efficiency on nests.

5.       Sheet size optimization 

It’s common for manufacturers to either shear-to-blank before punching or manually estimate the best sheet size for a group of parts.  Either approach is designed to maximize material use and minimize remnant management.  However, an expert nesting algorithm has the skill to forecast from a number of sheet sizes what material size would be the best for a bucket of parts.  Further, it can optimize from an existing array of standard sheet sizes minimizing the need for purchasing specialty sized stock.  Working with fewer standard sheet sizes or eliminating the shearing process not only saves material, but increases throughput and reduces raw material inventory loads.

6.       Tool Management / Preferred Tool List

The complexity of tool management takes turret nesting to a whole other level above and beyond that of more straight-forward contour nesting.  With powerful tool management and a preferred tool list, intelligent nesting software can optimize the tool selection for the turret to achieve several efficencies.  1) Minimize turret changes by selecting tools for the turret that can get the optimal number of hits per nest, 2) Minimize turret rotation and sheet movement by creating an efficient tool path, 3) Increase material efficiency by increasing the number of parts to be considered for a series of nests with a standard tool configuration in the turret.  If you change out the tools less frequently, use common tools to do most of the cutting, and increase the number of parts that can be cut with these settings, the user can increase material efficiency.

7.       Batch Nesting

Batch nesting, though not unique to the turret environment, dramatically increases material efficiency.  An Expert Nesting algorithm can look at a large bucket of orders, i.e. a shift, day, or week’s work on a machine, and consider all parts when optimizing nests.  With a large bucket of parts, there are by definition greater nesting combinations and more opportunities for nests with a higher material efficiency.  Automatically, a series of unique nests of 5, 50, or 500 sheets can be nested with the Expert Nesting algorithm looking as trillions of part combinations to find optimal efficiency in minutes.  For more detail visit here.

8.       Dynamic Nesting | Axiom VE

Dynamic nesting is at the heart of any material efficiency strategy.  With Axiom VE, nests can be calculated that consider all of the variables (priorities, change, due dates, throughput) a shop must contend with and still optimize material efficiency.  Multiple orders, progressive due dates, kits or assemblies, manufacturing requirements, rework and revisions for thousands of parts can simultaneously be considered, weighed for highest relative value, and optimized for efficiency.  It is precisely because the mathematical problem is made “harder” that the results can be so fast and material efficient.  For more on the science behind the algorithm visit here.