[pianotech] Puzzler 10/26/09

[John Formsma]

Nope, nothing to do with the grommets.  But I did correct the extreme lost
motion in my first attempt to remedy the problem. Didn't help at all. After
I'd fixed the real problem, the hammer was about 1/2" off the rail. So I had
to undo the lost motion "adjustment."

Go below the keybed in your thinking ... <G>

--
JF

On Wed, Oct 28, 2009 at 8:55 AM, pmc033 at earthlink.net
<pmc033 at earthlink.net>wrote:

>  Ok, John, I'll take a stab (nobody else I can see has a reply).
> The rubber grommets that connect the end of the key to the sticker wire are
> hard from age.  Somebody noticed that there was too much lost motion and
> used that square tool to take up the slack.  The grommet hardened with the
> keystick/wire at a certain angle, so that when the grommet is turned for
> adjustment the grommet is putting pressure on the keystick causing it to
> bind on the keypins.  If you remove the sticker wire, the key is free to
> move.  Connect it, and you'll get binding on the keypins.
>     If there are no rubber grommets, similar situation with the sticker
> wire- somehow it is binding on the key and not allowing it to move freely,
> though when it's disconnected the key moves freely.
>     Am I close?
>     Paul McCloud
>     Sa nDiego
>
>
>
> ----- Original Message -----
> *From:* John Formsma <formsma at gmail.com>
> *To: *Pianotech List <pianotech at ptg.org>
> *Sent:* 10/27/2009 8:21:33 PM
> *Subject:* [pianotech] Puzzler 10/26/09
>
> Was working on a 1971 Currier spinet yesterday, doing a 100+ cent pitch
> raise and minor repairs. (Yes, icky work, but bills is bills.) F6 wasn't
> repeating at all during the first pass, so I took some time to figure what
> was wrong. The note would play once and not repeat unless you really hit the
> key quite hard.
>
> The jack was the problem. It didn't return under the hammer butt ... much
> like when the jack spring is weak/broken or the flange is too tight.  But
> neither of those were the problem.
>
> Key friction wasn't the problem. Wippen friction wasn't the problem either,
> although I certainly didn't remove the action to check it. :-)
>
> What I found puzzling ended up being the clue to solving the problem: lost
> motion was considerably greater than any of the neighboring keys.
>
> Some tools involved in the repair were a Reyburn CyberHammer and a 8"
> action screwdriver bit (the one with a reduced shank for flange screws).
> WARNING: the previous sentence will not lead to the solution. It is given
> only to confuse and bewilder you. Pictures will follow that demonstrate that
> the repair tools were ones used out of necessity. <G>
>
> Good luck!
>
> --
> JF
>
>
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