In a message dated 12/28/00 4:55:40 PM Central Standard Time, JIMRPT@AOL.COM writes: << I have no doubt that leather tends to swell up when soaked with water but I don't 'think' that wool does so. Has anybody done any experimentation on whether wool changes size with moisture absorption? There has been much speculation in this thread based on the felt changing size and I wonder if it really does? Just a passing thought. Jim Bryant (FL) >> If wool didn't absorb moisture and swell, then what accounts for sluggish centers? Is it the wood around the bushings that swell to tighten the center, or is it the wool that expands that causes the problem? I would suspect the wool. That is why can use a Protek, or the old fashioned alcohol and water, to ease the bushing. Or is that just to free up the wool, which is being pressed against the pin by the wood that is swelling? Willem Whether the felt swells or the wood swells around the felt causing tight centers, it doesn't matter as long as the remedy cures. I was taught the water and alchol treatment then heating the whole action to dry. This was called "wetting the action", or "watering", or "watering the centers". Also a tip was passed along of using a wetting agent such as Photoflo to make the solution go into the felt and wood more rapidly. Later on I found Protek CLP worked just as well and did not need the heat treatment. There may be exceptions as I am limited in practice. I believe the guy who invented the center pin and felt bushing also discovered "wetting the action", because without this treatment I do not see how the pin-bushing concept could have survived. Say, I have never heard who did invent the center pin and bushing or when it first appeared and by whom. Can anybody shed some light on this? What were the alternatives or predecesors?...... Ever see a parchment hinge? ---ric ps (pssst, not enough time in your day? check out the experimental "best of" list, simply email remoody@midstatesd.net
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