Restoring Standard Action Valves
By Roger Waring
Sonja, Many thanks for your prompt reply and advice. I probably should have said that I am familiar with Arthur Reblitz' books, and the general testing techniques that he suggests such as that for air motors and the like.
What I was specifically looking for here was expertise on Standard valves and clearly you have a lot of that! There are a number of good pointers in your reply and I have taken note accordingly.
To deal with the other parts first, I tend to replace all auxiliary motor cloths anyway, including a full rebuild of the air motor whatever its state, as the cloth is usually old and ready to split at any time once the action starts being used again regularly. I tend to pay particular attention to the air motor to get the best possible regulation and smoothest operation that I can. Nothing sounds worse that a raggedy rag!
In respect of the valves, then: Yes, there is a card lifter on the pouch which I omitted from my description. They are fine, in fact the pouch board as a whole is in remarkably good order. I do not plan at this stage to even replace the pouch leathers on mine. I think that Dennis's is the same.
I like the incense stick idea - I can imagine that it works very well. My wife will think that I'm going to turn Buddhist or something! The rim of the wooden valve chest (where it mates to the gasket around the outside of the pouch board) is rather rough, suggesting poor manufac- ture. There are a few chips in the wood as well so I have lightly sanded the rims smooth and filled in the odd hole. I shall do the bench test as you advise, and I would now expect the gaskets to perform satisfactorily. First though I shall attend to the problem areas that you have identified.
1. The fibre guides. Although I had spotted the missing bushings, and sensed that this was maybe bad news, it was only when reading your reply that I realised that when laying the chest flat on the workbench, the valves naturally sit flat, and seal OK. Of course, when placed in the vertical position during normal operation they lay over quite badly, undoubtedly causing leakage. Lesson number one learned! Perhaps obvious, but my previous full restoration was on Simplex unit valves -- an altogether different proposition. (And quite enjoyable)
2. The valve leathers. They really are in quite good condition. The suck test that I described did not involve any pressing or force. I simply gently sucked on the metal seat sufficient to overcome gravity and then eased off until the valve dropped. I shall reserve judgment on them until the bench test is complete.
3. The small pneumatics (do you tend to use the term bellows for these in the US?) have cloth that is old and somewhat stiff. I plan to recover them all following initial bench tests.
So there we are. The first step is to contact The Player Piano Supply Co. in Kansas and see what they can send me. Do they supply ready- leathered disks covered to a general specification?! Or is that too lazy!
Thanks again and I'll let you know how the bench test goes.
Regards from Merrie England.
P.S. I've just been reading "The World Rushed In" by William Swain. A wonderful personal account and diary of the '49 Gold Rush. Is that an area of interest to you coming from Sacramento?
Roger Waring
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(Message sent Tue 25 Feb 1997, 02:10:00 GMT, from time zone GMT-0800.) |
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