Ken Goodman asked about sharpening arch and tube punches.  If you take
them to a local machinist or machine shop they will be able to help
you.  If you want to do it yourself you will need a metal cutting lathe
and a tool post grinder to get the best results.

The most time-consuming part is setting up the handle of the punch in
a 4-jaw chuck and having it run true so that you are then able to grind
it.  If you don't have experience with metal working I would suggest
you take my first suggestion about the machinist.

Walt Kehoe
Syosset NY