Ron, Ride 'em cowboy! When I 'resize' the plate holes, I pretty much use a schosh over. (Another technical term ascertaining to any particular thereabouts). I angle the drill as to the pin. This moves the bottom of the plate hole away from the top of the block hole. But then again, I could be all wrong. Jon Page ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ At 07:03 PM 12/30/97 -0600, you wrote: >Hi Del, Les, Theodore, and all the ships at sea, > >The major advantage I see to plate bushings, besides being a terrific >drilling guide, is that they supply an excuse to make the hole in the plate >big enough to clear the tuning pin. I don't claim that they have any holding >power by themselves, or that they minimize flag poling even. (I really don't >think flagpoling is a problem.) They KEEP THE PIN OFF OF THE PLATE. Sorry, >that wasn't shouting, it was emphasis. <G> Keeping the pins clear of the >plate lets the pinblock do it's job of getting a grip on the pin. A pin will >hold in a block even when the hole it's in is pulled oval by string tension >and humidity swings because the tension supplies enough friction around 270 >degrees of pin to hold the torque. On the other hand, if the pin is riding >the plate, there is no tension produced friction and the pin loosens in the >block much sooner than it would have with plate clearance. > >The immediate noticeable effect of pins riding the plate is feel. The final >problem in tuning any given string (after the string bearing points and >segment tensions are under control) is leaving the pin in a condition where >the bottom of the pin is "ahead" of the top, so it is torqued back by the >string tension in a way that the opposing forces of tension and torque >balance. The system is stable because it's balanced. When a pin rides the >plate, I find it more difficult to feel exactly what the bottom of the pin >is doing. Again, this is much worse in an older piano than a new one because >the block's grip on the pin is tighter at the top of the pin, than at the >bottom in an older piano with riding pins. The torque is so erratic from pin >to pin, with some of the pins not riding the plate at all, that I have to >switch "modes" back and forth so many times, and consciously fight the >process that the tuning becomes much more tiring. It's also more likely that >I guessed slightly wrong on final pin placement and I tend to find more >slightly noisy unisons in post tuning checks. > > >The long term effect is in the differences in pin torque. Each seasonal >cycle widens this difference between "riders" and "non-riders". The riders >get looser, quicker, than non riders. This is least noticeable in new >pianos, but becomes a real problem as a ten or fifteen year old piano that >cost as much as a room addition has a dozen pins too loose to hold string >tension. > >That's about it. Pianos with plate bushings tune easier than those with pins >riding the plate, and the pins remain tighter in the block, and of more >uniform torque, for longer than those without. > >Open blocks would be ideal, the best of all combinations. The issue, as I >see it, isn't really the bushings, it's the plate riders, or lack thereof. >Steinway could get a dramatic improvement in both long term tunability and >pinblock life by just drilling the plate holes bigger. > >Baldwin's granite pinblocks have the same troubles when pins ride plates, >but they are nearly as impossible when they don't. They ought to be using a >more forgiving material, like titanium, AND drilling the plate holes bigger. ><G again> > >Boy, I sure hope somebody out there agrees with at least SOME of this stuff. > >Still ducking, still covering, Ron > > > > >At 10:17 AM 12/30/97 -0800, you wrote: >> >>Ron, Les, Theodore, et al., >> >>I have a hard time getting too worked up over the controversy concerning >plate bushings. They were originally invented to be >>a drilling guide. And once the drill goes through them, they really aren't >good for much. After a couple of annual weather >>cycles the wood has tried so hard to expand between a rock and a hard place >(the pin and the plate) that the wood fiber is >>pretty well crushed. Not to mention the wear and tear from our tuning efforts. >> >>I spent about five years tuning almost nothing but Steinways. Without >bushings. I could never understand the reported >>problems folks were having tuning pianos without bushings. If the piano had >level pins (in the seventies and eighties none of >>them came that way, we had to do it during prep), consistent pin torque >(ditto), uniform string coils (ditto), etc., tuning >>stability simply wasn't a problem. I had a whole lot more trouble with >Baldwin's and their granite pinblocks -- but that's >>another story. Or Mason & Hamlin's with their plate bushings. >> >>I have long suspected that the fondness many tuners have for tuning >Yamaha's, etc., was simply that Yamaha paid much more >>attention to those details that actually do make tuning easier and more stable. >> >>The only plate bushing I've ever seen that might really be effective was >the one used by Knight for a while. (I don't know if >>they are still using it or not. Barrie?) It was phenolic and was hard >enough to resist being crushed by the flagpoling tuning >>pin during tuning. >> >>The system I really do like is the exposed pinblock. It is possible to use >both a shorter pin and one with a smaller diameter >>and still not have excessive flagpoling. It's a great system when done >correctly. >> >>Del >> > > > Ron Nossaman > > >
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