>Ron - this certainly MAY be true, but I sure can't fathom why. I would >think that the narrowest part of a diameter would have EVERYTHING to do >with how well a round pin fit in a bushing. Are you implying that there >is sufficient 'give' in the bushing to allow for no impingement on the >pin when the wood is 'pushing down' on it, even if only from two, >parallel sides? > >Explain to me the errors of my ways! > >Mark Potter Hi Mark, It may well prove that my ways are the ones in error, since I don't know precisely what the hole is doing, but here goes. If the hole is mostly enlarging, but closing in on the sides from that surface fiber swelling Don warned about, you'd get an oval hole. As bushing compression increases in the narrower part, doesn't it decrease in the wider part? If the whole hole is shrinking, but is still oval, the compression of the bushing is still an average resulting from the difference between the widest and narrowest axes of the oval hole. That's why I said I didn't think the round rod really told us much of anything, since it only detects the narrowest axis of the hole, and tells us nothing about the widest. Maybe Terry could grind the sides of the rod down some for clearance and use it to check for "ovalicity" instead of trying a bigger hole with a front keypin. That way he could still use a real world flange and maybe clarify the results of what he's already done so far. Let it cool first, Terry. <G> Then we can see what Jim B comes up with and how it compares to my quick and superficial bushing cloth expansion test. I still think the cloth is a, if not the major player here. Ron N
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