Pneumatic covering material
By Craig Brougher
|Darrell Clarke asked about pneumatic covering material. I have tried to steer everyone away from trying to use "pouch" leather for pneumatics for that very reason-- they deteriorate, depending on your climate and the amount of bacterial activity supported by your humidity and temperature. The old leather was able to last much longer than the new leather is able to, because it was tanned much differently. It was stretched and staked, which compressed it's thickness, tightened the collagens, and rendered more of the fats out of it.
Bilon came in two batches from the Player Piano Co. According to Durrell Armstrong. One batch had a "soft" inner side, caused by the fact that the polyurethane had to be "cured" but could not be put on together. So that meant a double curing of one side when the other was cured, which would harden the first side. Instead, they cut the time on the second side from what it should have been for a full cure, and it became a little gummy" after a number of years. The next batch had no such problem. I think that you will be all right.
Any polyurethane coated nylon is able to be Hot Hide Glued with the poly side down! That is the only glue to use on pneumatics, because it is the only one hard enough that will not slide, or allow hinges to go "whopper-jawed " after awhile. One thing about that, though-- always test first. Your cloth may have some kind of mold release that nothing will stick to. I've seen it once, and don't trust it anymore. Otherwise, Hot Hide Glue forms a perfect bond, and when you strip off the cloth, the polyurethane stays on the wood.
You do not need Bilon, and it is no longer made, anyway. Player Piano Co. has some of the finest pneumatic covering material available, so I would trust them.
(Message sent Fri 30 Aug 1996, 13:46:43 GMT, from time zone GMT.)