Die Quoting

Before you receive a contract to design and build a die, you must quote a price to the customer. Because many factors affect costs, and every die usually is one of a kind, quoting the tooling cost is not always easy. You must have a good understanding of sheet metal processing methods and the die design and build process. Understanding these factors is critical, because you can determine the die cost only after you decide the process steps. In other words, you must know ahead of time how many steps will be needed to make a given part. Some parts can be made in one or two steps, while others might require numerous steps.

Many quoting engineers keep historical records of quotes. They can look at previous quotes for similar dies, determine if their company made or lost money on the project, and quote the new tooling with respect to the last quote.

Many factors influence tooling cost. Among them are:

Type of tool needed

Delivery time

Volume the die must produce

Contract payment terms

Die building shop's location, capacity, and niche

Once the quote is submitted and the customer has approved the tooling purchase, you can begin designing and constructing the hard tooling (Figure 1).

Part Processing Methods

To help you get a good feel for the part the die will make, as well as help you interpret the exact part geometry, you likely will want to have a plastic model of the part made. This model can be passed on to the diemaker so that there is no miscommunication regarding the part's shape. You can make this plastic prototype part using stereolithography or a process called 3-D printing.

Forming Simulation

In most die shops the actual die design doesn't begin until the process, or steps for making the part, has been established. Many advanced shops use forming simulation software to help them develop and prove out their process before designing and building the die. This is especially helpful when the part has very difficult geometric features. Let's take a look at this virtual forming process.

Virtual forming, otherwise known as a virtual press, is a type of finite element analysis (FEA) software that can accurately simulate metal forming using a die. Metal drawing, stretching, bending, flanging, and ironing can be accurately simulated to help you develop the correct forming die geometry before you build the die.

The simulation shows the metal splitting, thinning, and wrinkling as well as how much springback occurs. It also can help you determine the correct blank type and size required to make the part. Using forming simulation greatly reduces the risk of designing and building a die that doesn't work. Keep in mind that the result of forming simulation is only as accurate as the data provided. You must enter the type of metal that will be used to create the part, along with its thickness and all of its mechanical properties. You also must provide information such as the coefficient of friction. After you enter all of the required information, you can virtually create the anticipated die geometry. Then you can perform the simulation.