Not sure why, Quickly pierce metals while leaving perfectly round holes behind with the Eastwood Metal Hand Punching Tool. This 17-piece heavy-duty power punch kit provides over 2,400 pounds of punching power for accurate holes. It’s a fast and clean way to start holes for drilling or form them for rivets, bolts and other fasteners. You can also use them to remove damaged rivets or, form more visible points for a metal shear. See this valuable tool in action by watching our video in the Eastwood Garage. Our metal hand punch tool works on steel, aluminum and brass up to 16 gauge and has a 5/8-inch jaw opening. It comes with six sizes of punch and die sets, and by using the adjustable work stop, you can form holes up to 3.25 inches inward from the edge. Shop at Eastwood for metal cutting tools designed by DIY experts with a 100% customer satisfaction guarantee. Works with up to 16 gauge steel aluminum and brass Punches between 1/8 inch to 7/16 Inch 3.25 Inch throat depth with 5/8 Inch jaw opening

It should, but spring steel is harder so it may accelerate die wear and take additional hand pressure compared to an equivalent thickness mild steel.

We don't recommend this tool with stainless steels. Perhaps if it is extremely thin (1/40" max) it will work for some time, but I'm just unsure of the durability in the punch and die bits for a material like that.

We do not recommend using this tool on stainless applications.

No, we do not have square punches available for this tool

Unfortunately no, there is not an available die option to produce this that we offer.

We do not recommend using this tool on stainless applications.

While it's possible since biothane should be much softer than steel we have never directly tested with anything other than metals.