Player Piano Valves
By Craig Brougher
There was a time when rebuilding a player piano meant recovering the pneumatics and replacing the old tubing and hose. And if you got a "professional job" that meant you might get the outside valve leather replaced as well-- if you were lucky.
That time is quickly passing into history. Few rebuilders in the past restored all of the working soft materials in a player piano, and as a result, many "restored" players of 20 years ago need valve jobs badly. Most of the pumps I've run into need new flaps and seats, even if they've had the covers replaced. And many of those rebuilders who got away with murder for years by not doing the valves, are discovering that their customers are rather put-out with the fact that in ten years, their "fully restored" players no longer play with the same energy and power that they once did, and some barely play at all.
If a player is anything, it is valves. Every valve in an automatic musical instrument is paralleled with every other one. If each has a total seepage equivalent to a pin hole (#70), a hundred valves seeping only that much equates to a 1/4" dia hole drilled through the pump!
If a Duo-Art valve (for example) in seemingly perfect preservation is placed on a tester attached to a bubble jar and a vacuum applied, the seepage through what seems to be "perfect original leather"-- that means, leather that seems tough and firm, and which cannot be fluffed up with an awl point, will leak from four to ten times as much per valve as that same valve after it is recovered and tested again. The reason is because it is old. It may look good, but it is not good. The collagen has been bored through with microscopic tunnels by bacteria. If you can see that, you've got better eyes than I have.
The flaps and seats in reproducer rotary pumps or in player piano pumps, for that matter, are perfect to look at, but leaky when tested. When a flap seat is removed from the inside of a bellows pump, it can be zipped off without effort because it is so dry-rotted. Doesn't really matter what condition the flap above it may be as long as it is porous and leaky. When you expect the new covers to last 50 years and leave old, dry-rotted leather inside that couldn't possibly last more than another ten or fifteen, you waste money and effort.
When old players which haven't been played for 40 years are rebuilt, they will function just like new after having new covers and tubing installed, and they will do a great job with the original valve leather for about 5-10 years. Then they start having problems, losing power and giving a ho-hum performance. The reason is partly because the inside valve seat leather of each valve is being "pulled apart" thickness-wise. As the pouch forces the valve poppet off its seat time and again, away from the suction, it loosens the leather and "fluffs" it. That opens the "tunnels" in the leather and causes it to cipher, and the packing effect of the vacuum on closed valves over the years gives way to the "shredding" effect that could not have bothered new, strong leather 50 years ago.
Owners who believe their player was totally restored with new valve leather throughout sometimes think they are seeing a minor problem. They call a repairman who may recognize the problem right away and tell them they need a valve job. He is hastily ushered out because "he wants to redo the valves which they know have already been done." Why not make him prove it? Have him remove one of the components right in front of you, open it up, and just see if it has new valve leather or not? You may learn something!
Having to rebuild your valves is not the end of the world. Most players can get a complete valve job without having to do everything else as well. So many player owners are missing out on some of the greatest rolls ever offered, especially with the new crop of arrangers we presently are fortunate to have. We are living in the greatest age of automatic musical instruments. The talents of a number of great arrangers who are no longer limited by financial and time constraints imposed by industry are being unleashed by the magic of MIDI and will become both rolls and computer programs which will soon play on many pneumatic operated players. This is a fantastic source of what is destined to become the best music ever offered. And the best of both worlds in the reproducer player business would be a pneumatic player with its fantastic dynamic range, coupled with the unlimited performance power of MIDI artistry.
This doesn't take away from the charm of the original roll, and the instrument will be able to play both. But it adds a dimension to its capability that you always thought it had, but couldn't prove it until now.
Don't believe in your pneumatic instrument's limitations as you may perceive them. It actually has the ability to play the instrument to the full capability of the greatest artist (or group of artists together) who ever lived. All it needs may be something other than 80 year-old leather to do it, and you're back in business! You are very close to hearing that instrument play as never before. Hope some will take advantage of the coming musical explosion.
Craig B.
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(Message sent Thu 16 May 1996, 23:01:34 GMT, from time zone GMT.) |
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