This is a pneumatic vacuum-powered reader for old-fashioned paper player piano rolls. (See 1st image)

Certainly there is a musical use for this, but I had other purposes in mind when I came up with it.

Specifically, I designed this for the purpose of being able to "program" pneumatic machinery.

More details available on my projects blog, here:
https://theheadlesssourceman.wordpress.com/2018/06/22/piano-roll-reader/

NOTE: The customizer may be of questionable usefulness. It could be fun to fiddle with, but to do any real work, I recommend downloading the openscad file.

Doesn't Matter

Doesn't Matter

You may run into size issues depending on the size of your print bed. You may need to slice, print separately, and glue together.

Most everything should print fine as-is.
(Haven't actually tried it, so...)

I cut the rollers in half, so you'll have to print both parts and glue together.

You need:
4x 608 skate bearings
4x 1/4 inch bolts
some kind of drive mechanism
a lot of vinyl aquarium tubing
some vacuum-controlled mechanism to hook it to

The .stl files should fit a standard player piano roll. I have no way of testing this, but if you try, let me know how it works out!