All too often people quote “Please quote the design and build a class A mold, capable of producing x, xxx, xxx, xxx parts per the attached design with a CpK of 1.33” What have you really asked for? Did they even ask the right question? Or, is it like your 8 year old daughter answering your question with “Because”, thinking it’s a complete answer.

What’s a ‘Class A’ Mold?

Capable of producing x, xxx, xxx, xxx parts over the life of the tool or annually?

Can the parts even be made to your design? Who says so?

A CpK has cut all your tolerances in half. Can anybody make those parts?

Simply shot-gunning the above quote to five vendors (plus the one you picked offshore only because they took out an ad in a trade magazine or you received one of their bulk e-mails) will only result in six completely different quotes with different size and different technology molds. This give you NO information. Unfortunately what usually happens is someone picks the low bidder and you’re stuck with what you have.

First you need to know your annual volumes. If you don’t have that take what marketing calls a three year life span and divide by three. There are several economic formulas that will tell you how many operating cavities you’ll need to support this volume. If you have big parts, this may mean multiple tools. It may also come back and say you need 250 operating cavities. Unless your part is really simple you haven’t got a prayer building a mold with that many cavities that you can control.

Now you need to know what kind of a tool is best for your part: Two Plate, three plate, hot runner, insulated runner, valve gates, tab gates, sub gates or a combo tool using any of the runnerless technologies combined with conventional sprue/runner designs.

What’s the answer? Actually it’s simple: COMMUNICATION

If you don’t know (exactly) what kind of tool, what technology (no Injection Molding isn’t the only one out there), what kind of steel (Why steel in the first place?) and how many cavities are the best for you, hire someone who does. This person you hire must be able to do several things:

1. Not only recommend how to write the request for quote, but explain to you in simple language why it’s written that way.
2. He must be able to come up with tooling sources that have proven that are familiar with parts similar to what you’re looking to produce, and show you the proof – while hiring your friends might be nice in these economic times, you’re betting the future of your company on this part and friendship has nothing to do with it.
3. He must use specific and exacting tooling specifications. There’s no such thing as a ‘Class A’ tool. Some people use the SPI designations, but if you look at those they are very vague.
4. He must be able to prove to you your mold isn’t going to be a Maintenance Money Pit before you build it.
5. He must show you industry standards for tolerancing and show you that what you want is within those tolerances.

While this consultant may seem expensive by the hour, remember a good tool costs about the same as a house. Paying a few thousand to assure it will do what you want is a good investment.

Once you’ve chosen a tool shop capable of making your mold, you must have a weekly progress report assuring you it is on time and on schedule. All too many people will place a job for several hundred thousand dollars and then begin calling the tooling source two weeks before its delivery asking when it will be ready. They usually find out it won’t be ready on time.

If your only interest is in procuring parts, you should have purchased this tooling expertise from a molding house. However, they should have demonstrated expertise making parts in the volumes you want to the tolerances you need before you give them the work.

Once you’ve built the tool, not only try it out to see if it makes parts, but OPTIMIZE the cycle. You’ll need your designer, engineer, quality person and buyer present. Before everything is over, get a signed document on the definition of a good part. In the end you only want a pipeline full of functional, cosmetically acceptable parts. Since you’re not willing to pay for the Crown Jewels, don’t ask for them.

Things to avoid:

“We have velly hard workers and goode machines” If you tooling source’s website looks like it was written by an 11 year old, it probably was.

“We’re doing OK’ – instead of a progress report. Before you place the job have them show you the progress reporting form they use. If they don’t have one, what does that tell you?

Never pay more than 50% of the quoted amount before you get good parts. Conversely, never hold back money ‘just to keep them honest’ – who’s being dishonest here?

“You can process that dimension in” Maybe you can, but why should you? You’re purchasing a mold that supposedly will give you the widest possible process latitude, not a narrow one to get a dimension correct because the tool maker couldn’t.

Having a good tool made is like finding a marriage partner. If you go in blind, you get what you deserve. If you take the time to see how the relationship will work before you commit to it, your life will be easier.

* * * * *

You can read this, nod your head knowingly and place the job with ‘the low bidder’ with a shop whose major asset is its location where you can do some really nifty shopping. Congratulations you just purchased a very expensive boat anchor. Or you can read this and begin asking questions about the choice of a vendor. OR you can admit you’re not a tooling or molding expert and in the interest of your own company, hire someone on a short term basis who is. In the long run you’ll save money. OR your can use this to scare the rats in the executive offices and go back to sleep.

It’s your choice.

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