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I've been running across pianos with bushings that are riding up the pin higher than the surface of the plate in some verticals recently. A couple that come to mide are a Baldwin Hamilton and a Yamaha U1. In some cases more than a half a dozen are above the plate about an 1/8 in. or so (mostly in the bass and tenor). I tested the strength of those pins and they were quite loose (turned easily with my pinky) but others in the piano without this "problem" were loose as well, so I couldn't see if they were a problem or not. Are these bushings that are peeking their heads out a problem, and is there a remedy?

Best,

Jordan

No. Bushings come in standard lengths, but castings vary in thickness. Bushings do not add any extra holding power to the pins.

Surprising to me, bushings are mostly to center the drill bit when the block is drilled at the factory.

--Cy--

No, bushings are to add support to the pins to prevent "flagpoling."

Not just during tuning, but I assume flagpoling during normal stress as well? If it's true Steinway has never used pin bushings, I wonder why ... just stubbornness, or don't they think their pins are under enough stress to require them?

Jeff

It's pretty common knowledge Steinway has a stubborn streak a mile wide. Whether or not bushings help with the flagpoling issue is a bit more controversial, but no piano should have a tuning pin torque that low. If you can turn them with your fingers, I'm frankly amazed if they'll hold a pitch at all. A tuning pin must really have at least 25 inch/lbs of torque to hold pitch at all.

No doubt bushings can be used as a support, but I really don't put a lot of faith in them. Check for pinblock damage, especially oil problems or cracking.

If there's no cracking or oil damage, I'd cautiously tap the bushing back in with a hammer shank and your 5 oz hammer, then see if it still has a problem and go from there.

Bushings might help hold the pin straighter during normal stress, but with flagpoling is pretty much irrelevant then as long as it's constant. It's really only a major factor during tuning.