In a thickness of 2.3mm on the board out of the hole 20, the die value of 20.2, the knife has a polished, punch 20, punch out of the hole often crack, and even bubble-like, clearly see the original surface separation Will this question how to solve it,
Punching out of the wafer but also pressure back to the product, in order to smooth, I die in the die where the small chamfer, the problem will not appear on this?
Plate too bad, for high impact plate or discretionary heating environment punching
