A Yankee screwdriver, the kind with spiral plunger which turns when
pushed in, was my solution.  I machined a screwdriver tip into a punch
with the center hole exiting out a side pocket.

With the rotary action, the punch cuts a delicate hole without dimpling.
I found it was easy to edit on the piano, slipping a piece of cardboard
under the roll, and the punch would retain a number of punchouts and not
be too messy.

Karl Petersen
Boise, Idaho