>OK, I know we've all been over this, but as a newbie associate I just have >to ask. When we apply an alcohol/water mixture to bushings to free up tight >action centers, doesn't that work by making the wood swell up around the >pin, compressing the felt? Nope, it works by softening the wool fibers and relaxing their springiness so they pack together and don't press so hard against the pin when they dry in their new position. > (Or do I remember this backwards: do we >do this to bushings to tighten up loose ones?) No, you're right. It's to loosen tight centers. >And wouldn't a one-foot plank of wood get longer (and bigger in each outside >dimension) as it expands, when soaked? Dimensions change tangentially, more than radially (nearly twice as much), and only very slightly longitudinally with MC changes. >Are you saying the outer edges would >move away from each other, but the walls of the holes would also expand >towards the outer edges? Yes, but the hole doesn't stay round. It gets oval and distorted because the wood changes dimension differently in all directions. >What if you drilled a hole near the edge and sawed >it off through the center of the hole? Would the straight edge move outward >from expansion, and the curved wall of the hole move inward? No, because there's another side still left to the hole - opposite the one you sawed off. You can get a hole with no sides at all to do whatever you want, but most folks don't seem to be all that impressed. At least in my experience. Ron N
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