> I wanted to call this subject "Players suck" just to > get some attention, but refrained. Technically > correct, but often mistaken for a disrespectful value > judgement. > > My problem: customer's Laffarge upright player, built > 1919, player action nicely rebuilt 1970, still very > clean and tight, works great, EXCEPT... > > When starting a roll, there is the sound of a major > vacuum leak. The spool turns slowly, but no keys > play. You have to turn the electric vac up to full > power, something pops shut, then the piano plays > perfectly, even after slowing the vac back down to the > minimum. The pump is tight, the motor is tight, the > action stack leaks only a little at the end gaskets. > > I think the action cutoff "gate box and vent block", > between the pump reservoir and action stack is > malfunctioning. It appears externally to be exactly > like the photo in Reblitz's "Player Piano...", page > 106, Illus. 6-17, third printing, 1986. > > I didn't have time to take it apart, but was hoping an > expert would have an idea why this valve would be slow > to close, needing very high vacuum. Any advice? > Quick fix? Something else wrong? > > Greg Graham > Closet player piano aficionado in denial It's likely an Amphion action, which means the valves are mounted upside down. Even with a with a good rebuild and a minimal 0.030" valve gap (neither of which is likely), 80+ valves all leaking that little bit until enough vacuum can be generated to suck them all up to seat will drain the system down. There's no field repair for poor design, so I'd expect you won't fix it with adjustments to the stack cutoff. Ron N
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