Pins: surprisingly complicated
Most of the historical washers or collars were made of multiple parts of very thin metal stock. Each layer was punched out of a sheet of rolled metal (brass, bronze, nickel, silver, copper, sometimes even gold).
Most of the historical washers or collars were made of multiple parts of very thin metal stock. Each layer was punched out of a sheet of rolled metal (brass, bronze, nickel, silver, copper, sometimes even gold).