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Technology Focus

Changing with the Times - Technology Advancement in Die Making

by Bruce Byrne, Southeastern Die

May-June, 2003
The manufacturing of steel-rule dies has always been considered a labor-intensive process. And until recent years, it was. The die boards were cut with a jigsaw blade, the rule was bent by hand to fit into the board, and the rubber was all placed on the die board by hand. Today, technology has streamed-lined many of these processes, making die making more of a science than an art as the industry has changed.

Laser Cutting
I was working in a folding carton converting plant in the late 70’s when I first heard of laser dies. The block die was the predominant die used in the cutting process, and the laser concept was hard to imagine, primarily because the term laser seemed like something from outer space. Additionally, the cost of the laser machine was extremely high, making it difficult to justify for most converters, and even most die makers.

Over the past decade, the cost of lasers has decreased dramatically while the cutting speed and accuracy has increased. Cutting speeds have increased from the first 150 watts that cut wood die boards at 6 inches per minute to 2000 watts that cut up to 125 inches per minute. Although the technology gains and cost reduction have made purchasing a laser cutter a much more feasible option, folding carton and graphic finishing companies still have a difficult time justifying the purchase. What laser cutting has accomplished is to give the die maker the tool to meet rapid turnaround and provide the equivalent in accuracy to the block die. The following is a list of advantages provided by laser cutting:

  1. Accuracy of the cut to +/- .005.
  2. Repeat accuracy of duplicate positions on dies.
  3. Accuracy of repeat die boards.
  4. Quick turnaround.

When I shifted to sales in the die making industry in the late 80’s, there were converters still saying that they would never buy a laser die. NEVER SAY NEVER!

Rule Benders
So we came into the 90’s with this great capacity to cut die boards but to knife them was still a bottleneck. Again, I heard the phrase from die makers that a machine will never be able to bend rule. The first auto rule benders had some shortcomings such as calibrating, notching, and mitering, etc. But as technology in the CAD programming and tooling of the benders advanced, it closed the gap in limitations. Will the next step be a bender that also inserts the rule? We’ll have to wait on that. Auto benders provide several advantages:

  1. The rule is bent in one pass even with complex bends.
  2. While duplicate rules are being made, the die maker can be knifing the die.
  3. The turn around on a knifed die has been greatly reduced.
  4. Repeat orders are done from a stored program.
  5. Coils are used which improves inventory control.

Water Jet Cutting
As the quest continued to control costs and minimize turn around time, the die makers found another technology tool to help them - the water jet. Using a CAD program and a water jet machine, die makers can now make a custom fit set of rubber for dies in literally minutes. Yes, it really looks nice and perception is sometimes 90% of success, but it contributes to the following factors:

  1. The process decreases time for die makers to rubber dies. This doesn’t cut cost of the dies but helps decrease turnaround time dramatically.
  2. It also balances the dies so that it reduces makeready time for cutting. This is a cost benefit that the converter realizes.
  3. Additionally, this balance decreases the number of carton nicks and their sizes.
  4. Finally, with high-speed die cutters, the consistency of water jet rubber has aided in obtaining higher run speeds.

There are several water jet machines on the market and each company will have to research which one best fits its needs.

Stripping
The stripping section of the converting process has received constant attention because of the higher press speeds. Additionally, this process must be efficient in order for blanking to be successful. The move has been to develop tools to eliminate bottom pins for maximum waste removal. Effective waste removal eliminates hand sorting and jamming in the blanking section. Again, machines are being developed to manufacture these units to reduce labor and increase efficiency.

Blanking Tools
The last area I’d like to touch on is blanking tools. The drive to reduce costs and delivery time has thrown much attention to this part of the process control. If the converter uses universal tooling supplied by the machine manufacturer, efficiency and labor is a significant factor. Most converters do not have this capacity so they must rely on the die makers for this tooling. Making the welded female blankers is time-consuming and the tools are very heavy. Using new technology with aluminum rails and a combination wood top and/or welded inner grid has changed managers’ thinking about blanking. This new female blanker has given us the same durability, quicker turnaround, and less cost. Foam male blankers have been available for some time, but cutting the foam was a drawback. The pushers had to be cut on a jig saw and complex shapes were too costly to make. With the availability of the router and water jet, that obstacle has been overcome. This unit has fewer parts than the traditional constructions of wood, stand-offs, and rubber, so it has reduced cost and turnaround.

I would like to conclude by restating what I said earlier - never say never! What we think is impossible today will be routine tomorrow. Steel rule die making has developed from a totally labor-intensive process to an almost completely automated system. That automatic rule inserter may not be far behind!

Bruce Byrne is a technical/sales representative for SDC International (formerly SouthEastern Die Co.) headquartered in Decatur, GA. Any response or questions can be directed to (800) 358-2388.