[CAUT] Capstan predicament

[Nancy Salmon]

Dear Jim;

We had a dealer locally who sold  russian pianos for a while under a dutch
name. As their tuner is not a tech I'm occasionally called in for tech
assistance.

Keys had to be eased and some front rail pins moved. What I discovered was
that the keyframe had the density of cheesecake. Front rail and balance rail
would crush/splinter at the least disturbance. Keys were also soft and
frail, causing the "sticking" and warping in the first place.

I suspect a pandora's box.

Nancy Salmon RPT
Frostburg State University, Maryland

On Jan 16, 2008 12:06 AM, Jim Harvey <harvey.pianotech at gmail.com> wrote:

> This is not a CAUT matter, but I'd like to request some options OTHER
> than my first couple of instincts -- those include landfill and
> marshmallow roast.
>
> The "piano" (being overly generous) is a J Becker. Means nothing?
> Okay, an approximately 10-year old Russian-made studio. First service
> call, touch resistance was like that of a kitchen table. Did not
> explore causes at the time. Second call followed a visit by the
> grand-children, who reportedly "broke something".
>
> Enter Harvey, thinking broken keystick, jack saddle, or other. NOT.
> One of the capstans was sheared off level with the keystick. More
> investigation revealed that capstans are 1) non-standard size,
> requiring a crescent wrench on the shoulder; 2) are pot metal,
> complete with casting seam lines; 3) threading on screw portion are
> course thread -- wood screw style; 4) screw body seems to be thinnest
> at point of entry in keys.
>
> Even on the first call, before this experience, I had planted seeds
> for a replacement piano, despite its short service life. Not sure at
> the moment whether that option will be taken. You see where this is
> going...
>
> I'm not unfamiliar with pot metal capstans, but other times I could
> remove them. I can likely find appropriate replacement capstans, do
> any necessary plugging and drilling, and so forth. It's dealing with
> an entire set of potentially sheared off stubs that's the problem. How
> can I be sure of the potential? On the obviously broken one, the
> homeowner, an accomplished word-worker who builds grandfather clocks,
> was going to attempt removing the stub. After he left for his shop, I
> discovered the pot metal, stopped his pursuits, and let HIM try to
> unscrew another capstan. It snapped off.
>
> A chapter member suggested killing off (breaking) the existing
> capstans, and starting a line of new capstans adjacent to the old. I
> don't know whether this would work, and if so, whether it might make
> the touch weight even worse. I thought of nuking the existing caps
> with a soldering iron, even at the expense of charring the wood, to
> help removal. Somehow through all of this, I keep envisioning the
> metal equivalent of a plug cutter for wood, but don't think such a
> thing exists.
>
> Any similar experiences/solutions out there, or am I just over-reacting?
>
> --
> Jim Harvey, RPT
> <harvey.pianotech at gmail.com>
> <www.harveypiano.com>
>
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