Piano Player Repairs

Oh great, I ran out of pneumatic cloth. Guess I need to send some money and an order to the player piano guy.....

Meantime I'll work on the key pneumatics.

The cloth is a mess. I should have known life would suck when I noticed white glue on the intake ports. Oh great, did dad use WHITE GLUE HERE?

https://i.imgur.com/tripaqY.jpeg

Oh god maybe. This stuff requires a LOT of heat with the air tool; worth having. Almost brought out my SMT air soltering ...

First step is to take it apart.

Screws came off easily enough and one of the arms. But the other arm was solidly attached. A little heat from my air gun loosened it up and it finally came off. We'll put those to the side and fix them later....

https://i.imgur.com/2qUuiOh.jpeg

Taking off the ...

One of the most important things a player piano needs to be able to do is rewind a roll and shut itself off. This is done by a special signal on the player bar that is supposed to engage a pneumatic to throw the piano into "rewind" mode when it's hit. If this does not happen properly the piano will ...

While working under the piano I noticed that a lot of the air leaks were caused by the fact that the pipes going into the valve boxes and various pneumatics were.... well, loose.
https://i.imgur.com/c9HS2HA.jpeg

As in you could turn them. You can see this in the above picture of the duo art valve ...

A quick pic of the unit in the piano.



Everything clears, nothing is binding, however I do need to do a lot more work on the piano. Several of the pipes to the valve boxes (most of them) are loose and need to be re-glued.....

Whelp, got the Duo Art box completed. The second (Accompaniment) set of stacks went together a bit rougher than the first, but they're holding vacuum and gauged to specifications.

I did make some minor but annoying errors. Worst was mistaking the locations of the screw holes and putting one set of ...

Very good news: I unlocked the top screw on each of the arms and turned the bottom screw. They bottom screw is a jackscrew to adjust the position of the knife valve in the box. If you don't know to loosen the top screw on the arm, you will strip the adjustment jack screw.

Both jack screws are good ...

Final thought: Tried ironing the junction between bellows 2 and 3. It doesn't collapse under normal vacuum and barely collapses when the other bellow is blocked off.

Given the leak is small, there is no clue where it is, and to be honest the dynamics work fine I'm going to declare this "good enough ...

Leak update. With proper hose, bellows 1 and 4 hold vacuum fine.

Bellows 2 leaks a bit, but not if I plug the hose to bellows 3. This indicates a leak between 2 and 3. Same with 3, it leaks back through two. However with 3 covered the pair of them hold vacuum.

This.... might be an issue. I think I ...