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Posted By: Dans Piano Service wind motor - 07/26/06 05:26 AM
Hi all. I am a piano technician but am recently interested in old players. Iam working on rebuilding a wind motor. I have been very carefull to make everything as air tight as it can be, wich I have been succesful at until I reached the slide valves. Am I expecting to much for them to be completely air tight because they are wood on wood, or is there some trick to get them there. I have managed to get the trunk, pneumatics and the connection of the pneumatics to the trunk air tight,but the slide valves are a different story.
Posted By: Grandpianoman Re: wind motor - 07/26/06 09:35 PM
Dan, you might want to do a search for "player piano repair" and send off an email to one of the people who repair them for a living..... they may give you some help. Also, a good book source would be the Art Reblitz book on player piano repair....you can google that, or use www.bookfinder.com

GP
Posted By: CTPianotech Re: wind motor - 07/31/06 12:15 AM
The two wooden surfaces sliding against eachother need to be sanded flat+smooth. Work your way up to 320, using a VERY FLAT sanding block. Dry graphite powder works extremly well as a lubricant. Greasy lubricants will gum things up in the long run.

Rich
Posted By: David Estey Re: wind motor - 01/31/07 10:55 PM
Unless the motor itself has splits or cracks at the point of contact of the slide valves to the wind motor, I would respectfully warn against sanding - because as CT Pianotec just emphasized VERY FLAT - he means VERY FLAT, and if it is off at all, it could make the motor useless.

The slide valves are sucked on to the surface by the power of the bottom action through the govenor (in play) and then full power from the bottom action (in rewind). As long as a generous amount of DRY graphite is present between the slide valves and surface, and there is no warpage or other such inconsistancy,(that WOULD need to be sanded as Rich said) There is no reason to worry about loosing pressure there. If it is not working properly, it is because the slide valves are not regulated to open and close the phewmatics smoothly in the proper sequence.

If you are loosing pressure, the first question is "were the valves, pnewmatics and bottom action rebuilt?" If no, then most of your problem is there.

Is that the issue? loss of pressure?

Dave
Posted By: fourthgenerationpianorestoration Re: wind motor - 02/16/07 04:13 AM
I agree with everyone ,you also should make sure the reroll(govenor) is adjusted right and not leaking, this diverts the (vacume)-pressure from the valve chest and the tracker and pnewmatics, durring reroll.Most books will give diagrams to.I also fold 1000 grit wet/dry sand paper used in auto finishing in half so the ruff surfaces are facing out slide this under the valve slide.Slide with a little presure so the paper rubs the block and then the slide.This should equalize the unevenness between them.If adjusted properly the wind motor doesn't take much vacume to work with plenty of tork.Do use plenty of grafite there and on the cam shaft points.
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