A: As an example, let's say you need to punch .875" diameter holes in 3/16" type 304 Stainless. The formula begins the same as for mild steel:
3.1416 x .875 (Dia. Of Hole) x .187 (Mat'l Thickness) x 25 = 12.8 Tons for mild steel
Because stainless steel has a higher shear strength, a multiplier factor of 1.40 is required.
12.8 (Tons for MS) x 1.4 (Multiplier for stainless) = 17.9 Ton per hole required.
For this and other tonnage calculation formulas, click here for Technical Data page 110.