> >I have to ask, Ron, have you ever broken a pin? (Don't worry, we'll let >you keep your RPT card even if you have not had the pleasure.) I really >thought everyone had, but maybe I'm wrong. I broke one many years ago >and my impression at the time was that I had been careless about seating >the tip properly on the pin. If we're not dealing with a high torque >situation, you'll probably get away with it. For several years, there >were several local 'shops' spitting out repinned pianos with obscenely >high torque, so stories of broken pins were not uncommon. > >There is a tendency to bend the pin whenever we attempt to turn it in >the block, no matter what tip or technique we use. If the tip contacts >the pin only at the top on one side and the bottom of the other - which >is what happens when the tip is not seated properly, then bending forces >are exaggerated considerably. > >Pins are not wrenched off when they break, they are bent/snapped off. >At least that's how it felt at the time. > >Carl Root, RPT > Carl, Yep, I sure did. I broke one about five years ago in a block I had drilled particularly tight because of where the piano was going (steam heat). The pin parts with a sort of tearing feeling because it's not hard enough steel to snap, but rather twists off like a wood screw, or grade 1 bolt that you over torque. I'll bet everyone knows *that* feeling well. I don't see how it is possible for the tip to not contact all four corners of the flats at once, unless either the tip, or the flats, aren't uniformly symmetrical. It seems to me that you would have to pull on the hammer in a direction significantly off the rotational plane to do what you are describing. The flats on the pin would tend to automatically square the tip up when torque is applied, and it would be pretty tough to counteract that tendency. Isn't that the reason they are made that way, to maximize the contact area between the pin and the tip and minimize the damage to the pin? A tip that is the wrong size, poorly made, or badly applied to the pin, will chew up the corners of the flats pretty quickly, but it chews up all four sides, or corners, at once. In any case, a broken pin happens so seldom that I would think it would take a lot of lifetimes of empirical evidence in normal field work to make a compelling case for poorly seated tips breaking pins. How about all those cheapest and most poorly made of all possible tuning hammers, with the, if possible, even more cheaply and poorly made tips, in the hands of all the band teachers, newbie tooners, preachers, and random hobbyists skulking about under the lids of helpless pianos? From what I've seen of the low end hardware out there, it doesn't seem to be possible to properly seat some of those tips on any known tuning pin under any conceivable set of circumstances. Shouldn't we see more (any) second hand tuning pin breaks from their tuning attempts, under the circumstances? Realistically, I doubt that they replace all those broken pins, leaving no visible evidence that they had been there (except for the chewed up pin corners) between service by tuners who have never had a pin break. There is one particular tuner that I follow occasionally. In every one of the pianos I find with his name inside, there are a number of obviously bent tuning pins. I don't know if he ever breaks one, but he didn't break the bent ones (or they would have been replaced by straight ones), and if a sloppily seated tip is contributory to bending pins (the better to break them), then it ought to leave plenty of obvious evidence of impending doom before any breakage problems become evident. Ron
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