Die Science: Who’s driving this thing?

Wow! The last few years have been a whirlwind for the tool and die building and sheet metal stamping industries. New high-strength materials are being introduced; more and more tools are being built overseas; spring-back and part-cracking issues are at an all-time high.

Over the last few years, I have had the opportunity to see many political and sometimes just plain l’foolish decisions being made regarding processing and purchasing of tooling. Some of my adventures have been so frustrating, I’m prompted to ask: Who is driving this thing? Who is really making the decisions with respect to how a part gets processed? Who decides the number if stations a part will be made in? Who decides which tool steel will be used and how much the tooling will cost?

Some of the answers may shock you. Keep in mind that my intent is not to upset or point a finger at any one person or department, but to inspire you to take a look at your own process with the goal of improving them.

Product Designers

This whole process starts as soon as a product designer begins to design a stamped part. Every decision the designer makes regarding part material, product tolerancing, and part geometry affects the number of dies needed, the size of each die, the tool steel being used, the lubricants necessary, the press capacity, and the speed simply, every line, every hole, every bump, every flange, and very bend adds cost and process steps. Every tolerance specified can dramatically drive tooling cost. The product designer, perhaps unknowingly, starts the ball rolling on what could end up as a great success or disaster. Product designers might engineer the car, but they are not usually in the driver’s seat.

Process Engineers

Process engineers are responsible for determine the methods and stations necessary to turn a flat sheet of metal into a finished piece part that falls within the part design tolerancing. Most good process engineers known the number of steps necessary to make an acceptable part.

So are they the ones driving the tooling decisions? Although they are responsible for determining the number of stations needed, they are doing only what is necessary to make the parts as designed. So no, they are not driving.

Die Designers

These folks are responsible for engineering the tooling that will execute the process established by the process engineer. Although some of the decisions they make will affect tooling cost, they are making these decisions based only on pre-existing die building standards or past experience. They determine the material that the car is made from, but they typically are not driving it.

Stamping Engineers

Stamping engineers typically determine if the process can fit into the press. Stamping companies usually are limited to trying to make a part in fewer stations that it really requires. And the process needed to make a given part often is based on the bed size of the press, which is risky business. If it takes eight stations to make a part, it takes eight stations; attempting to do it in five is not a good idea. So are they driving this thing? No.

Purchasing Staff

Yes, tooling guys, the moment you’ve been waiting for! And you probably already know the truth: the purchasing staff members are not only in the driver’s seat, they often are in the carpool lane driving 20 miles under the speed limit.They have a budget that the tooling must fall within. It doesn’t matter if it takes two or 22 stations to make the part, the die must not exceed X dollars. They often don’t care what the part is made of, or if the press is big enough, or what tool steel the die needs to be made of. They only know that last year the tooling for a similar part cost X dollars, so in the interest of reducing tooling cost, you will be allowed up to 10 percent lower cost than last year’s tool.

Cost Versus Value

Cost versus value comes up time and again. For example, a certain company has a very high about of scrap and downtime because of poorly performing dies and tooling. Most of the failures are because of poor tool steel selection, poor processing methods, and poor die workmanship.

Needless to say, the company ends up struggling financially and looks to the purchasing department to help save money. Tooling cost is reduced, and dies come in that are just short of being made out of Elmer’s® glue and sawdust. That tooling fails, and so does the company.

High-quality dies cost more, but as the saying goes, you have to spend money to make money! Dies are not a liability; they are an asset, an investment in the future. Understanding the difference between cost and value is crucial.

Today's toolmakers are being asked to produce dies that can form advanced materials into complex geometries with tight tolerancing expectations. Every one of these changes is driving a big increase in tooling cost. Many shops no longer can use conventional tool steels for forming and cutting—they are forced to use premium tool steel cost, but require more machining time. The sections often have to be large as well. Yet tool and die shops are expected to reduce tooling cost and lead-times?

The Solution

Education and communication are the foundations of any successful company. Everyone involved in a part's production must have a complete understanding of the political and financial constraints that purchasing people must deal with. Communications with each other will help determine which costs are value-added and which are wasteful.

No single department should drive the decisions; they should be made as a group in the best interest of the entire organization, not a department or individual. Until next time...Best of luck!