Diagnose This! (A puzzler)

[Avery Todd]

Correct the position of the jack under the knuckle????

Avery

At 08:32 PM 07/15/03 -0500, you wrote:

>Piano: Late model Geo. Steck small grand.
>
>
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>The Problem: G#3 failing to play on a hard blow.
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>Observations: Plays with perfect reliability on soft blows but misses 
>almost every time on hard blows (jumps up a little but no where near the 
>string).
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>
>Possible causes eliminated:
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>
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>1.       Key stick is NOT cracked or broken
>
>2.       “Catcher Interference” ruled out by the umpire—hammer tail is NOT 
>snaggin’ or draggin’ on the buckskin.
>
>3.       Hammer, shank, and knuckle are fine. Observed, from marks on the 
>knuckle, that it was only resting on one side of the rep lever. Hammer not 
>centered well on strings either. Adjusted the lateral position of both 
>hammer and rep lever to better align everything. Had no effect on the 
>problem. (Before you squawk, the piano is pretty new; the hammers 
>virtually grooveless*.)
>
>4.       Examined whippen assy. No problem with flanges or centers. No 
>cracked or broken parts. Nothing missing. Nothing unhooked or out of its 
>slot, etc. All in like new condition.
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>
>
>Clues:
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>
>    * Let off was early (maybe 3/8”) and turning the adjusting dowel 
> didn’t seem to change the letoff point. Hmmm …
>    * Jack height was good but jack was too far forward. Aha! Jack isn’t 
> getting fully under the knuckle and is tripping out so fast on a hard 
> blow that there is nothing to lift the hammer! Yes, yes!
>    * Turned the jack regulating screw … jack did not move any further 
> back. I could push it back, but it just came forward again when released.
>    * The wippen spoon was bent a little, more angled than on neighboring 
> whippens … almost as though someone (factory?) was trying to get that 
> jack into position. Straightened the spoon. No help. Turned the 
> regulating screw until the felt and dowel were no longer even touching 
> the spoon. Jack stayed right where it was.
>
>
>Hint: I had to remove the jack to fix the trouble but there was no 
>problem, whatsoever, with the jack. In reinstalling the jack, I used a 
>certain tool that I already had at hand … (what a giveaway!)
>
>
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>Puzzler: If I said any more, it wouldn’t be a puzzler now would it? What 
>simple thing was necessary to restore this key to full power and proper 
>regulation?
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>
>
>Prize: One of my regular clients. (Note: I get to pick which one, and I 
>have someone specific in mind.)
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>
>
>(To Joe Garrett: Thanks, Joe. And feel free to submit an entry.)
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>Alan R. Barnard
>
>Salem, MO
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>*Grooveless? Like, wow, Man, that is so un-glad. I am, like, totally 
>bummed for you. I really feel for that felt. Have a flower.
>
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