<< Does anyone know right off the top of their heads the amount(s) of vacuum needed to run an old player piano?>> It varies a lot with the leaks, and condition of the valve leathers and cloth, but the average player should work pretty well at 20 inches of water vacuum. I used to do a lot of player work. The tighter the player, the less friction here and there, the better it was rebuilt, the less vacuum, and volume of air, it needed to play well. In a complete rebuild, I worked to achieve a standard of playing well (if quietly) and continuously at 5 inches of water vacuum. If it doesn't work at that level, then tape off parts and test and redo until it does play well. The old, unrebuilt players that have leaky cloth, cracks in the pneumatics, etc., will not work until 80 to 120- inches of water vacuum, which is very difficult to pump by foot. The leaks can often be overcome with vacuum cleaner motors that easily can produce 100 to 120 inches. If you are getting into rebuilding, test every large pneumatic by itself, every component at the lowest possible level. It should, for example, take a minute or longer for a sustain pneumatic to expand after it was exhausted and sealed off. If it takes 5 or 10 seconds to fill when sealed, you have a leak that needs to be chased down. Do that type of testing to every component and the final player can perform fabulously well. If you rebuild a player really well, and you set it to "PLAY", you should be able to just walk up to it, stomp quickly just once on the pedals, and it should play the roll and produce the music starting very loud and diminishing to nothing over perhaps three to five seconds with just that one pedal push. Bill Simon Phoenix
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