Greetings Devlon, I've used the nylon cauls, both one-shoulder and two-shoulder types, and found them to work well. I have discussed the differences between the two with other technicians, and found that the type of caul (plastic, brass, aluminum, and wood) are largely a matter of personal preference. I also use a set of .152" brass cauls on larger bushings, and yes, I keep the cauls that I'm about to use on the edge of my Hold-Heet glue pot. It seems to let the glue stay liquid for a little extra time to fill all the nooks and crannies between the wood and the felt, and it is also handy to keep your fingers warm on cold winter nights. However, it is my opinion that technicians spend too much time worrying about the 'perfect' key bushing caul, and spend less time on removing the old bushings with little damage to the wood, selecting good quality bushing cloth, applying the right amount of glue so that the cloth binds well to the wood (usually hot hide glue, but I know a respected senior RPT who used aliphatic resin glue and his bushings were perfect, even years later) , and sizing the balance hole so that your keys don't rattle after a long bushing job. If all the above factors have been attended to, your bushing job will be a respectable one. Cauls are important, but merely one aspect of a complex operation. Cheers! Rob Kiddell R.P.T., P.T.G. C.A.P.T. Student Edmonton, Canada http://www.planet.eon.net/~atonal/atonal.html
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