I must agree with Robbie on the economics of re-producing music rolls.
A laser just doesn't give the economic benefits to justify the purchase
price.  Commercial lasers are still expensive because (a) that's what
the market is prepared to pay and (b) they are built robustly for years
of accurate service.

The price of low power laser modules has come down over the years and
a good home technician could build a laser cutter at reasonable cost,
but as Robbie points out, would there be any benefit over the existing
mechanical systems?

The reason model kit suppliers are going to lasers is because in their
industry there _IS_ a large time and labour saving.  The old way of
producing kits involved tracing the many individual drawings onto
templates, then making numerous metal clicking knives and die cut
plates, then "clicking" the balsa or wood sheets.  Now the kit
components are simply drawn as, or converted to, CAD files that drive
the laser.  The craftsman has been replaced by someone who can press
"Go" on a computer panel.

A roll cutting laser would be quite simple, utilising an input roll
holder, a take-up roll holder, a transport roller driven by a stepper
motor and a carriage with the laser head that can move back and forth
across the width of the paper, driven by another stepper motor.  There
are simple 2-axis stepper motor software programs available to tell
the laser when and where to burn a hole, then move the paper forward
to the next note.  In principle it's not any more complex than a
computer printer and in fact someone has pondered on the possibility of
utilising a computer printer as the basis for a roll cutter.  Computer
sign and label makers work on the same principles but use a sharp point
to cut the paper.

The problem is that a simple laser machine as described would be slow,
say 1 or 2 holes per second.  To speed it up requires higher power,
faster stepper motors and a more rigid machine, and there goes your
budget.

Of course the other major problem with a laser cutter is transcribing
the original roll accurately to a computer file in the first place.
So you need a roll reader; that could comprise another set of feed
and take up roll holders and a transport roller.  The notes could be
read by a strip of LEDs positioned above the width of the paper and the
position would come from having a position encoder on the transport
roll shaft.  This is not unlike a computer scanner mechanism and in
fact one of the brands of scanners has just such a set of LEDs in it's
reader bar.

If someone had a complete laser cutter, that cost him, say, US$ 30,000,
how much would he have to charge to recoup his outlay and ongoing
labour costs and just how many rolls would he get to make?  Would you
pay an extra $20 per roll for a laser cut version?

Sorry to be a wet blanket, still !

However, there probably will be someone one day who comes up with a
laser roll cutter -- because he can!

Colin MacKinnon