Synthetic Pouches
By John A. Tuttle
Good Afternoon,
I have noticed a marked increase in the number pouch failures in Universal type players and all units using the Wurlitzer type block valves. In the Universal type units, the problem usually starts with the failure of the auto-sustain function and progresses rapidly to the note pouches. (Two customers didn't even notice the missing notes or inoperative auto-sustain until I ran the test roll.) In the case of the Wurlitzer type block valves, the related function gets weaker and weaker until it quits.
In the case of the block valves, the bottom can be removed and a leather pouch installed. Also, having spoken to Durrell Armstrong (Player Piano Co. owner) about the problem some time ago, I was not surprised to find leather pouches in the new ones I recently purchased.
However, since the only economical repair of the Universal type stack involves the use of similar preformed pouches, I attempted to find out why they failed (in such a relatively short period of time as compared to leather) so that I had some assurance they would last for at least the period of my five-year guarantee.
The information I did get is not totally complete because some of it was lost when it left the engineers desk for transcription and duplication. I was told that locating the test results was "too involved" but basically this is what was found:
Pouches made with *perflex deteriorate and break due to hydrolysis (decomposition of a chemical compound by reaction with the elements of water). After discovering this fact, the material was changed to *tuftane which doesn't break down in water. The change-over occurred about two years ago. The manufacturer believes that the tuftane pouches will last 15-20 years.
* I'm not certain about the spelling of "perflex" or "tuftane" because the engineer couldn't remember the exact spelling and the words aren't in any of my dictionaries.
Musically, John Tuttle
|
(Message sent Sat 7 Sep 1996, 20:23:48 GMT, from time zone GMT-0400.) |
|
|
Mechanical
Music Digest™ Archives
