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MMD > Archives > February 2025 > 2025.02.21 > 01Prev  Next


Video Recordings of Laser Cut Piano Rolls
By Piotr Barcz

I've been in Poland since the start of February and I brought all of
my rolls that I made for myself using my Spencer Chase laser perforator
to play on my Francis Bacon player piano. It not only has a functioning
tracking pneumatic (rebuilt by Lance Reed five years ago so it's snappy
as heck) but it also has a tight pouch system, unlike my Conway piano
which struggles to even trigger notes on new QRS rolls if the punches
are one row in length.

Here's the video of the three rolls: https://youtu.be/JmUThWJVpXI 

[ 1. https://youtu.be/JmUThWJVpXI&t=203s Who?
[ 2. https://youtu.be/JmUThWJVpXI&t=894s I've Got a Feeling I'm Falling
[ 3. https://youtu.be/JmUThWJVpXI&t=965s I've Got a Feeling I'm Falling
[ 4. https://youtu.be/JmUThWJVpXI&t=1396s You're the Cream in My Coffee

One roll of the old run was punched on low quality Kraft that cost me
more than the new stuff I started using that's better, not to mention
I hadn't had the perforator setup with the paper running against the
rear bearing roller, which allowed a bit less squareness to be achieved
as the paper was going under the pinch roller.

As I noted in the video about that first roll, there are ragged edges
that might've been cut when I had 3D-printed guides from Spencer that
I inevitably mounted in such a way they were impossible to adjust
properly. I replaced them with the wooden guides again and got slightly
better results afterward.

You can also see the wandering of the holes after cutting multiple
full-length slots in succession. By the time those long back-and-forth
moves had been made and then the edges cut, the paper had shifted and
then the bridging is misaligned with the head slot. This was still
present on the second run but not to that horrible extent.

However, despite all of that, the roll did track well enough to play
properly without any issues, even when it was marginally close to
opening up wrong notes on a particularly bad jerking of the tracking
system.

Oh -- Also at the time, the paper I had been using had expanded from
humidity which made it necessary to cut the roll overwidth by 3 mm and
then dry it on the radiator, leaving the paper a bit crinkly but still
playable. However the width was then 285 mm [11.22 inch], QRS's width,
the marginally wide enough size to track properly.

The second roll was the first roll I cut after resetting the perforator,
fixing the missed focus of the laser, and speeding up cutting speed
from 750 mm per minute to 5000 mm per minute! The roll finished cutting
in an hour and a half or so.

Improvements to note: Much better edges that still do wander but not as
fast or rough as with the old paper and the paper itself is much better,
smoother, and being cut at the right size from the getgo.

However I did notice some hole size inconsistency and this is more than
likely because the wooden guides are warped, and on fast and aggressive
backstrokes (which is what 5000 mm per minute cutting speeds do) the
paper would sometimes twist enough to make a bit of a loopy looking
hole.

This hasn't affected any playback accuracy as the hole still starts at
the correct point but I'll give any criticism credit because it looks
absolutely ridiculous. (Just wait 'till someone figures out how to cut
scalloped edge holes!)

The last roll is from the same run: a Blu-Cut Duplicate this time
without the Duo-Art coding. (I don't have a Duo-Art piano so I don't
need Duo-Art coding, and I didn't have a scale for it at the time). The
Tempo issues I believe are present because I removed the guide rails
from my wind motor which lets the valves slide around a bit. I'm not
sure if that actually caused any of the slight Tempo inconsistencies
because I've run rolls at one foot per minute with no Tempo problems.

Anyhow, that will be solved when I recut the roll at the full length
or just under it, depending on if I need to round the punch rates to
get bridging to be of the correct thickness. My cut runs at a Tempo
of around 55 or something (35 on my Tempo meter which is two feet
per minute too fast).

The original roll (which also has a faster indicated Tempo than I like
anyway) runs at like Tempo 90 or 95, but I think if playing at my Tempo
with whatever change in the punch master there may be to get bridging
right, the Tempo will be probably closer to Tempo 80.

Hole sizes will all be correct too but, if I can, I will test play that
first Duo-Art cut on a restored Duo-Art grand to make sure everything
expresses right.

Piotr Barcz
currently in Poland


(Message sent Fri 21 Feb 2025, 10:30:09 GMT, from time zone GMT-0800.)

Key Words in Subject:  Cut, Laser, Piano, Recordings, Rolls, Video

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