Cutting Die Ordering

[FAQ]

Cutting Die Ordering
Mark B. Baril, Cut Smart Engineering & Manufacturing, Inc., Waitsfield, VT, USA

Is cutting die ordering an art or a science? Communication between the diecutter and the diemaker rests at the heart of the diecutting process.

Converted products have a huge range of identities. Throughout the world, we converters produce everything from labels, gaskets, and envelopes to folding cartons, medical devices and specialty “whatchamacallits.” No matter what your product is, there is common ground that involves a single process. That process is diecutting. Whether you are manufacturing heart monitors or cupcake packages, missile parts or greeting cards, stamps or walking shoes, the communication between the diecutter and the diemaker rests at the heart of the diecutting process. With open and specific communication, the production rates, quality of the finished products and profit margins will have their best chance of being fantastic! When the diecutter and diemaker have a system in place to exchange information accurately and openly, the process of ordering tooling works to everyone's advantage. This article will outline the specific information that needs to be passed down the line when any of the many different types of cutting tools are ordered.

Critical Project Information:

* Material being cut
* Quantity to be cut
* Shape or design to be cut
* Final product quality requirements
* Press/production specifications
* Die specifications
* Extras/add-ons
* Delivery date
* Pricing

Material being cut

Every time you order, allow your diemaker to know the basics of what his/her tool will need to stand-up to. By providing this information you close the miscommunication gap. For example, both materials can be run on the same press and in the same shape, but there's a monstrous tool difference when going from .010" (.254mm) polyester film to .1875" (4.76mm) cloth inserted rubber.

Provide this key information:

* Material type/name/style/color
* Thickness
* Durometer/hardness/shore
* Sheet size or web width
* Grain or material orientation
* Printed vs. non-printed
* Are there laminations that will be cut? If so, what are they, and what is their relationship to one another?
* If this is an uncommon or unfamiliar material—provide a sample.

Quantity to be cut

The diemaker needs this estimated information to determine what the tool should be made of and how it should be built. Will it need to go through one sharpening or re-knife in its expected lifetime, or will it be worn and ready for sharpening within a week? Does it need standard or ball bearing type bushings? Each specific type of tooling can have built-in features that will allow it to both last longer and be reworked more easily. It may cost a little more, but as the old saying goes “you can either pay now, or you can pay later.” On the flip side, your project may be such a short run that cutting back on material strength and advanced design features will make no difference to the process or the product. In this case, why pay for more when you need less?

The other thought processes that will be stimulated by this quantity knowledge are those of speed and secondary process elimination. Depending on the run size, the feed rates, waste removal, ejection, material usage, etc., all become increasingly important and are oftentimes bettered as a direct result of tool engineering and collaboration between the diemaker and diecutter. Make your diemaker think! Everyone will be happier in the long run!

Provide this key information:

* Number of sheets/impressions/parts to be cut per set-up
* Number of sheets/impressions/parts expected during the life of the tool
* Is this likely to be a repeat cutting job? How often will it repeat?

Shape or design to be cut

Perhaps the most important detail to be communicated, the drawing of the part needs to be handled with care. Both the diecutter and the diemaker must maintain a system of document control within their shops to ensure that the correct drawing is used. Once the shape has been determined, all the other questions and answers can start to flow.

Provide this key information:

* What is the shape? What is the part used as? Is there a print or a CAD file that specifies the final part design? What is the drawing number/revision? Is there embossing, creasing or any other “during the impression” detail we need to know about?
* What is the layout? How many can we fit within the press/tool/material limitations?
* Which direction does this image need to face within the tool/press to account for press type, repeat lengths, feed rates and material related direction? The “material related direction” may be caused by grain, printing, directional laminates, etc.
* What is the yield expected for this part within the constraints of the material size?
* What amount of space is needed between the parts and on all sides of the complete layout to get the cut material through the press?
* Which side of the part does the drawing show? This is extremely important in printed and multi-layer materials!

Final product quality requirements

Details related to quality are very important to the diemaker. If the tool will be cutting a part that needs to have a final tolerance of ±.003" (.076mm), a typical steel rule die or clicker die is not be the best way to go. Better results will come from a matched metal, milled die, or other tight tolerance tool. The diemaker must also know if your product is machine-filled, assembled or otherwise dependent. Does it require tight tolerances on the finished set-up size as well as the finished blank size? To produce a machine-filled folding carton, for instance, a laser-cut die with matched phenolic or steel counterplates may be the only way to achieve a perfect box.

Provide this key information:

* What are all the tolerances for the final part - are there areas of the part that have larger/tighter tolerances?
* Are there any uncommon quality requirements for this part?
* What is the edge quality requirement? Just how burr/dust/sliver/crush-free does the part need to be?
* Are there any non-contamination specifications? Some tooling may incorporate materials that will contaminate the parts. Open cell sponge rubber ejection in medical product tooling is a typical example of a troublemaker.

Press/Production specifications

Finally, you may be saying! Yes, this is the area where most tool makers and diecutters focus their attention when building/ordering a die and rightly so, because if it doesn’t fit the press, it is not going to work. The details, when it comes to fitting a die to a press, are straightforward and should contain the basics every time you order. Just keep in mind that the questions to ask are close to being the same for all presses, but for every press type, model and operator there is a different set of answers. A common platen press may have the same chase size and bolt hole pattern as all the others made like it, but if your customer decided to stay with the .923" (23.44mm) cut height because they already had a rack full of dies when they bought the press, this detail becomes extremely important.

Provide this key information:

* What type of press? What type of die? Is it a clicker press or a soft anvil rotary press? Is it a steel rule die or is it a matched metal die?
* What is the base size and dimensioning the press will take? Length/width/thickness/gearing/number of teeth/maximum opening/closed height/bed and frame specifications/chase specifications, etc.
* What type of feed mechanism is being used? Hand, suction, grip and draw, nip roller, belt, etc.
* Where does the overall cutting image lay within the overall die size?
* What will the die strike against? Will it be cutting against or through a steel cutting plate or a soft cutting pad/belt/blanket?
* How fast is the press expected to run? How many impressions per hour will it need to make?
* Is there in-line stripping or blanking? What are the specifications for these additional tools? That is an enormous question—we’re going to have to leave the specifics for a later article.
* How will the parts be ejected from the tool? Are the parts being fed through, blanked down, being pushed out with rubber, being put back or staying in the web/sheet via a stripper plate? Within each one of the techniques of ejection comes a whole new set of questions. If your diemaker has answers to the questions asked so far, he/she will be able to guide you towards ejection that works well the first time.
* How will the waste be separated from the parts?
* How will the parts be delivered through the press and to the final customer? Will the tool be kiss cutting to a liner or pushing the parts through into a box?

Die specifications

Given all the answers to the questions asked so far, the engineering specifications for the tool to be made will become clear to the diemaker. The rule type(s), clearances, base material and sizes, ejection, coatings, processing methods and all the other details for your particular type of tool will all become automatic. These die specifications become your base of information for this type of project on this particular press and should be used over and over again.

Extras/Add-ons

There are additional services that a diemaker often adds to make the tooling complete. With them, a toolmaker may gain an edge on the competition. Without them, the cutting may not go forward. Tell your diemaker if you need: stripping tools, blanking tools, stop blocks, pre-press nicking, die-strikes, vinyls, QC reports, makeready sheets, counterplates, embossing inserts or any of the other items you need that are not considered a normal part of the complete tool. As with all the other parts of the die, communicate the details that go with each of these extras.

Delivery date

Simple enough—when does the diecutter need the die in-house? For the diemaker, this communication is critical. A perfect die a week late can become a major part of the quality equation. On the other hand, a super-rush tool, with all the headaches that go with it, that sits on a shelf for a month, can lead to bad feelings in an open relationship. What type of time frame is realistic and what is absolutely out of the question?

Pricing

If the tool was not quoted prior to the order, it is important for the diecutter to know how the tooling will be priced. Good communication on pricing means that the diemaker and diecutter have an open exchange on what is possible to do for the amount of money allowed for the project. Diecutters must remember that a little more money toward the tool can save time and money in production. Diemakers must remember that a die with a few less features may not make any difference to this particular production situation. If you get to the point in your relationship where close estimates with a little room for adjustment in price in either direction become the norm-you have a great working relationship.

Provide this key information:

* What was the quoted price?
* Have changes been made since the quote?
* If the tooling was not quoted, what is budgeted for tooling?
* Do you want to get into some type of a negotiated long term contract situation for tooling?

Last, but not least

Is this the right type of die/press to cut this image, in this material, in this quantity?

Now there’s a tough question that must be asked and answered on at least your big run projects. Yes, we must all deal with the equipment we have on hand, but can it be produced more easily and quickly with a different type of processing? I have found this to be one of the most important questions a diecutter can ever ask a diemaker when on unfamiliar ground. By jumping right in and ordering the same type of tooling every time, you may miss an opportunity to improve your methods. Many of today’s very savvy diemakers will also be able to direct you toward alternative cutting methods if your run is a short one, a long one, or unusual in any way.

The answer to the “is it art or is it science” question can go both ways. There is the science of diecutting that is controllable, repeatable and predictable on the one hand, and on the other hand we have the confusing art of good communication. The object of the ordering game is to turn the communication of the details into a science. What has worked before and what has not? Where did we fail and where did we nail it down just right? Once the diecutter and the diemaker have established all the guidelines that make a certain type of project work well for a certain press, they can use these rules over and over again to produce perfect results. The trick is to document your experience and use it every time during the ordering process. If the experience isn't there, build upon the questions you ask and the techniques you try to make your new experiences count the next time you crank up the press. If you have an ordering system in place right now, I hope this article helps you add information to it. If you are just starting to build this type of communication with your diemaker, I hope this article gives you a big head start. Good luck!