So what's working?

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czunit
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Posts: 11
Joined: Sat Jul 18, 2026 12:34 am

So what's working?

Post by czunit »

That's an interesting question. Being that I was seven when I last worked on this there are some gaps in my knowledge but there is a surprising pile of information in here rattling around. So after a bit of work, here we go:

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  • Main pump: Operational. Pulls 40+ inches of water at the main regulator. I think this is good.
  • 1 inch hoses: Old, need replacement. For now I have taped the ends to make them more snug on the fittings. Stops the leaks and allows things to work
  • 1/2 hoses: Same. One of the hose brass fittings to the rewind valve system was loose; re-glued with hide glue, now tight.
  • Small hoses: Seem good oddly enough. No cracking or leaking.
  • Main vacuum regulator: Works. Rewind cuts out the player system and the vacuum on the end side is pretty constant.
  • Wind motor: Works. Oddly enough no leaks, dad fixed this well and used leather on the edges so it's quite tight.
  • Governor: Works. Holds a one minute flat time to go 7 feet on the test QRS Duo Art roll. So tempo is good.
  • Rewind: Works but needs adjustment. The dual bellows is meh, should recover, used some rubber sealant on the edges for now.
  • Replay: Does not work. System rolls out and stops either setting.
  • Auto off. Works, but anemic.
  • Duo Art expression pneumatics: Totally shot. I don't think dad rebuilt these, and they have totally fallen apart. Probably 100+ year old pneumatic cloth, consider this inoperative. To bypass it I ran a length of 1 inch hose directly to a T fitting and to both sides of the wind chest. Oh well for now.
  • 88 key pneumatics: Mixed. At least 4 fell off the bottom board, and several other notes are not working. The ones that fell have cracks in them at the seams and need to be recovered. Oddly enough most play very well and do not show evidence of damage or leaking. I wonder if this is because us kids would crawl under the piano and play it by pushing up on the exposed rods. Oh well.....
  • Soft and sustain pedals: Inoperative. They need adjusting but for now I'll figure those out later.
  • Tracking: Needed adjustment. Tracking was way off but after loosening the bolts and cleaning it up the piano tracks the test roll well.
So next goal will be to recover one of the key pneumatics and get it glued back to the board. Hopefully without having to remove everything as I have no clue how to do that and it would probably mess up a LOT of other things that I am not yet ready to do. One step at a time if possible.
czunit
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Posts: 11
Joined: Sat Jul 18, 2026 12:34 am

Re: So what's working?

Post by czunit »

So I have a total of five of the pneumatics off the piano. Yes, the looked good. Yes, they leaked when blown into and sucked with one's mouth. Yes, all were recovered. Here are some pictures.

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Here you can see number 13 and 14 together. 14 was re-covered and passes both a blowing and sucking test. #13 kind of passes it but as you can see the flexible sealant makes the overall pneumatic shorter and it doesn't move as well. So recover the thing! It's not totally impossible.

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A view up in the piano. The glue does not look too great there; I'll remove it to make a clean surface then re-install with a bead of fresh glue. Hide glue of course. It's going to be a bit complex as I will be doing it upside down, will hold in place for 5 minutes then use tape to keep it up till the glue solidifies.

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This is.... very interesting. It looks as if dad used a paper gasket or something between the bellows and the board. Not sure what that is or why, but maybe it was the style of repairs in the 1970's? Don't know.

The one on the right is even more interesting. It looks like the glue was overheated and applied burned or something. I do not know. What I do know is that all of this glue is coming off....
czunit
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Posts: 11
Joined: Sat Jul 18, 2026 12:34 am

Re: So what's working?

Post by czunit »

Oh this is interesting. When I went underneath to clean up the board I knocked three more off.

Why? They all had the burned glue. I think I found an error that dad or mom did 50 years ago; a batch of the pneumatics did not go on properly and the glue failed.

On the positive side it's limited to 9 of them so far. On the negative side it's 3 more to cover. I'll re-cover even though they did play perfectly because removing them is a pain.

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Birds of a feather :-)
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