There’s a tool called a die blank which should work, with a male
punch and a female slot, like a circular or scrapbooker’s novelty
paper hole punch.
There’s instructions on how to make your own: called the R T
blanking system,
I’ll leave further discussion to people who actually know what
they’re talking about.
Sebastien Bailard
RepRap.org - self-reproducing 3D printer project.