Method :

Take a junk drill - chuck it in up-side-down.
e.g. grind off the drilling part and use an old shank.

Now where you want to drill - drive this blunt end into the
metal.

Friction heat the spot - turn it blue and go to the next.
Once all are blue - use a set punch to mark the hole and
drill with a normal drill.

Martin

wrote:
You may want to check how hard the the sawblade is first.

I needed a spacer for a dado blade and decided to cut one from an old
10" blade. I tried to drill a number of 1/8" holes near the desired
diameter but only 3 of 40 holes were able to be thru drilled. The
drill would cut well for the first .02" then hit a hard center
core. I finished the task with a cutoff wheel.
Perhaps the center is intentionally left hard?

OTOH have you looked at the Freud website? They do make a variety of
smaller blades.


Best of luck