Die cutting tonnage refers to the force it will take a die-cutting machine to cut a given product using a specific publishing material. While most die-cutting presses have much more pressure capacity than they will ever need, the occasional job or material will test the limits of a company's press. For this reason, it is important to be able to calculate needed tonnage going into a project, which means planners need to know the material strength and image size, as well as other factors specific to the machine.
Calculate the number of "inches of rule" you need to cut. This is the linear length of your cut. For each inch, assume you'll need anywhere from 300 to 500 pounds of pressure -- 400 pounds for standard computer paper.
Determine the square inches of rubber you will need to cut. The stacks of paper you'll be cutting with your machine have rubber strips holding them together so that your cuts will go through the same spot on each sheet. For each square inch of rubber, assume you'll need 50 pounds of pressure.
Add together the tonnage capacity you'll need for the project. For example, let's say your project involves 500 inches of rule, and your paper has 1/2-inch rubber strips on either side of the blade -- 500 x 400 = 200,000, and 500 x 50 = 25,000, for a total of 225,000 pounds, or 112.5 tons.