Monday, Feb 4, 2013

John:

Your email with the accompanying marked-up photo on Jan 29 in reply to my previous inquiry about installing the 916 kit for auto rewind was helpful. Using that information I have "dry" installed the device to verify that it can be fitted onto my piano. I have attached three photos of my setup for your review and comment. My questions:

1) The vacuum hose is fitted to one of the two holes at the top of the device using the brass elbow. What do I do with the other hole in the device?

2) I would like to attach the vacuum hose from the device to the piano reservoir with a 3/4" vac flange elbow through the same wood panel where the electric vacuum pump hose flange is attached. (See photo .... 0006). Do you have a suitable 3/4" flange for that purpose? If not, how would you attach the device vac hose to the piano reservoir, going through that same wood panel? What hardware would I need?

3) What is the purpose of the 4 round-head screws in the top end of the device? If they are adjustments, how do I use them?

4) A white plastic elbow and a cork stopper came with the kit. What are they for?

5) The photo for the Automatic Rewind Device in the " Supplies" section of your website Player-care.com shows some kind of black fitting near the screw-eye on the 916 device, but mine does not have that . What is it, what does it do, and why does mine not have it?

I still do not understand what is actually happening internally when the rewind mechanism functions. Could you give me a word description of the purpose of each of the connections, and of what is happening with each step of the change from play to rewind?

Thank you very much for your help!

Lee

Hi Lee,

Everything looks to be in good shape.

1.) Use the cork to seal the other hole in the device. You can use either plastic glue or epoxy, but you must create an air-tight seal. (I can't remember for certain, but I might have also thrown in a little silver 'cap' that fits into the hole. Either the cork or the cap can be used to seal the 'other' hole.) BTW, you can install either the plastic elbow or the brass elbow into the device.

2.) The easiest thing to do is drill a hole in the blank-off plate that you made (great idea BTW -that way you have the original plate intact in case you want to return the system to its original state at sometime in the future) and use 5-minute epoxy to cement the other elbow in place. If you really want a flanged elbow, I can sell you one for $15.50.

3.) The four round-head screws are used to secure the two block valves to the device. The springs are there to help prevent the over-tightening of the screws. If the screws are too tight, the wood might crack and destroy the block valve. They are correctly tightened at the factory and should require no attention.

4.) I gave you the other small white elbow in case you want to use hole #1 and hole #87 to trigger the device. You have it tubed for just hole #87, which is the normal configuration. The function of the cork was already explained above.

5.) The black (actually gray) piece near the eye-screw is a flimsy rubber plug that was supplied to seal the 'other hole' in the device. The supplier now includes a cork to do the job. I just haven't gotten around to taking another picture......

The auto rewind device functions the same as any pneumatically operated device that's found in a player piano. Basically speaking, a valve controls the flow of vacuum to a bellow. When the valve is "on", vacuum sucks the air out of the bellows, causing it to collapse (or close). When the valve is "off" (or the valve changes state), air from the atmosphere is allowed to flow into the bellows, causing it to relax. In the case of the auto rewind device, there are two valves working in tandem which supply the vacuum to the bellow.

Hope this clears things up.

Musically,

John A Tuttle
Player-Care.com

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