Hi Eliyahu and MMD.  I have two punches, one for 88-note and one for
65-note rolls, that produce a strip of iron-on tape about 7 cm long,
with three side-by-side rows of holes punched in it (two rows in the
case of the 65n punch).  I separate the rows with a scalpel.  The
iron-on tape is called Crompton Tissue and was obtained from the UK
for me by Julian Dyer.  It is a little tougher than Filmoplast-R
iron-on tape, which doesn't stand up too well to the punching process.

To apply the tape I first cut away any remaining bits of bridges with
a scalpel.  Then I put a sheet of Teflon ironing sheet under the roll
before positioning the strip of bridging tape over the damaged long
perforation.  I fix the tape in position with a few quick dabs of an
iron.  (To avoid domestic discord I have my own piano roll iron.)

Then I place a second Teflon sheet over the top of the tape and iron
it on properly.  The Teflon sheet underneath stops the exposed bridges
from sticking to whatever surface the roll is resting on and the top
Teflon sheet stops hot adhesive leaking through the tape and onto the
sole plate of the iron.

The advantages of iron-on tape are that one can move it around on the
roll until it is positioned exactly and it doesn't stick and that once
the glue is cooled it is no longer sticky and so any exposed bridges
don't stick to the next layer of paper when the roll is wound up again.

John Phillips in Hobart, Tasmania