Sticking centers again

[Susan Kline]

Hello, Dan

If it were my problem, I'd remove the a few of the wippens, and remove the
jack center pins. Then I'd test the fit without a pin, and see if it _is_
"wood against wood" i.e. rubbing around the birdseye. If the problem isn't
connected with the center pin, then alcohol will be fairly useless, I
should think. 

While you have the jack center pin out, look at it _very closely_. Plating
failure has been a problem with some Samick center pins. The symptoms are
sudden seizure which gets worse as the piano is played, while most notes
are okay. That is, the notes may work okay when you first start playing,
but seize as they warm up. Later in the process, they are very, very tight
all the time. The crumbles of plating snag the wool fibers, which tangle.
Looking at a pin where this has happened under magnification, you will see
the brass showing through and score marks where it is rubbing in the bushing.

If the plated center pins are failing, _lubricants are not the answer!!!!!!_
They'll just gum things up down the road without affecting the cause of the
trouble. Repinning with plain brass pins after easing with Don Mannino's
broaches will give you a permanent fix. 

Good luck.

Susan

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At 06:59 AM 9/24/98 -0600, you wrote:
>Esteemed list:
>
>	Having done a little homework, I'll venture to reopen the question of
>sticking jacks on a small Samick grand, almost new. It went through some
>high humidity this summer when the air conditioning in the business went
>down. Around 20 jacks are sticking, apparently wood against wood. I've
>installed Dampp-Chaser dehumidifiers under the soundboard and keybed, a
>15 watt just under the jacks, and a humidistat. 
>
>	I have on hand a plastic bottle with narrow steel tip, isopropyl
>rubbing alcohol 70%, ethyl alcohol 70%, and Garfield center pin
>lubricant. My questions are: 1) Which alcohol, if either? 2) How much
>water? 3) Would Garfield's be better? I know I'll want to use a hair
>dryer or let it sit 24 hours, and may have to repin. The work will be
>covered by warranty, and the dealer is willing to replace the action if
>necessary. TIA.
>
>	BTW, I checked archive PT 054-96 at
>http://www.webcom.com/wind/ptsearch.html
>
>Dan Eumurian, R.P.T.
>Just starting to see the fall colors in…
>La Crosse, WI :-)
>
>

Susan Kline
P.O. Box 1651
Philomath, OR 97370
skline@proaxis.com