It has been pointed out to me that there is an apparent contradiction
in my posting about Triola rolls.  At the beginning I say that it is
not necessary to punch the small timing holes in new rolls, only that
the number markings should be correctly positioned.  Later, I say that
when playing the 'number only' accompaniment one should play the bass
string on the first beat, where the number appears, and the three
stringed accompaniment where the small hole appears for the remaining
beats of the bar.

I was assuming that the player is sufficiently musical to be able to
hear the beat and play along at the correct beats of the bar.

In retrospect, I accept that it would be better to cut the timing hole
to assist the beginner.

I see no reason why the same punch could not be used for all holes on
the Triola roll.  There is a wide margin on both sides of the music
punchings, quite sufficient for a single hole to be punched into the
left hand margin for timing.

The rolls have a pitch of about 5 mm with a hole size of 4 mm, leaving
1 mm between tracks.  The margins are 15 mm at each side so I suggest
a 4 mm timing hole should be placed to leave 3 mm of paper between
itself and the edge.  This will leave an 8 mm unpunched strip for the
numbers to be printed.

Best wishes to all aspiring Triola players,

Nicholas Simons
East Midlands
Great Britain