Dishing Sheet Metal

Drilling is done in sheet metal only when piercing cannot deliver the accuracy required.

Dishing sheet metal. Maximum depth of dish can be sheared flanged on the model 87 using the equipment that is standard on the machine. Dishing the metal into a hollow or depression in the end of a log works but unless you have a lathe to quickly turn out a bowl shaped depression you must carve a hollow by wood chisel or simply repeated pounding. Flat heads and dished heads 9 230 mm. Drilling tapping counterboring and countersinking are the usual operations done in sheet metals.

I will show you how to dish sheet metal. While sinking is a relatively fast method it results in stretching and therefore thinning the metal risking failure of the metal if it is sunk too far. Both of these latter methods take time and all three presuppose a handy wood source. Reverse dished heads can be accommodated with additional tooling.

Sinking also known as doming dishing or dapping is a metalworking technique whereby flat sheet metal is formed into a non flat object by hammering it into a concave indentation. For example on a formed part when holes on different features need to be coaxial the accuracy obtained by machining may be required. The maximum major axis diameter is 9 2750 mm with a maximum major minor axis ratio of 2 1.