How
to Make a Razor Hole Saw
Cutting a clean hole in a soft wood is a challenge. As far as I know,
no tools are made commercially that can do this — particularly in all the
odd sizes we need.
Brad point drill bits work very well in a drill press as long as the bit is
sharp and you work very slowly. Unfortunately, my drill press can only
handle bits up to 1/4". The other problem is that brad point bits come in
limited sizes.
I have been making punches and hole saws for a long time. They work
well but sometimes require a bit of tweaking before they work properly.
If you are working with balsa 1/16" thick or thinner or 1/64" plywood then
you can make a twist punch. A twist punch is simply a piece of tubing
sharpened on the inside or outside depending on the application. In
either case the punch has no teeth.
A twist punch doesn't work well for thicker woods because the plug jams the
punch and prevents it from cutting deeper. |