> It's also >conceivable that the same lose of stability and tunability that could ensue >from pins pulling forward in an aging block might, in fact, be restored by >the plate contact. Compare that with the cumulative effect of an tight >tuning pin in a new (5?6? ply) block, with the additional torque from plate >contact, and without the ability to use forward pin flex to equalize string >tension. These are different animals. I'm comfortable with the former, >not the latter. > >Regards, > >David Skolnik Except that the torque resistance goes down when that old pin contacts the block, not up. As the plate takes the pin load, the pin exerts less pressure on the block. Since the friction coefficient of steel on iron is less than that of steel on wood, the net holding power is less. In a new block, it's not much of a factor, but it's noticeable in an old block - sometimes to the point that a plate rider may not hold, while a non rider right next to it will. That's the real world difference. The subjective part is similar, but a little different. The objection I have to the feel in tuning is this. An unsupported flagpoling pin will react immediately to the hammer and string, and when you decide on your equilibrium point with all the bearing surfaces, torques and tensions involved, it will be pretty much where you think it is and stay where you put it. This is good. With bushings, you have some friction and support just under the coil, so the same set of criteria you use for tuning a bushingless pin works with bushings, only it's a little less touchy. This is, I think, better. That's the ease of tuning part. Long term stability shouldn't be any different. When a bushingless pin is riding the plate, you get the flagpoling support, and some friction. Not as much as with a bushing, but considerably different than the pin right next to it that isn't riding the plate. This, again in my opinion, is un-good. My techniques for tuning these different set of pin responses differ enough that it's a hassle working it out for each pin. If they were all bushed, or all not bushed and not riding the plate, the feel is much more uniform throughout. That's my take. Maybe I just resent being forced to pay attention when I'm tuning. Also, if the pins aren't supposed to be riding the plate, why is it that so many do? If they are supposed to be riding the plate why is it that so many don't? Proposed detection of intent being present in the design should require that they should all be doing the same thing, wouldn't you think? Or are we back to either lack of intent or precision in execution? Something here still isn't right. Rebuilders don't have an excuse on this one, because they have the power to do it right, whatever that may be, or at least uniformly. Ron N
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