[CAUT] Capstan predicament

[Ken Zahringer]

Hey, Jim,

I think the marshmallow roast is a great idea.  Bring some hot dogs, too.

BUT, if the client won't go for that, the item you want is on page D-30 of
your Pianotek catalog, "Broken Screw Extractor".

Reminds me of an episode I had with a lovely Schubert upright (product of
Belarus) several years ago.  It had dowel capstans on wires, and keys made
of the Russian equivalent of cottonwood.  A moderately hard blow drove the
capstan down into the key.  Spent most of a day removing, drilling,
plugging, redrilling, and reinstalling.  It was a brand new piano, under
"warranty".  After I sent the bill, the dealer wouldn't return my phone
calls and six months later the distributor decided the job was worth $100,
take it or leave it.  Live and learn, right?

Regards,
Ken Z.


On 1/15/08 11:06 PM, "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?

-- 
Ken Zahringer, RPT
Piano Technician
MU School of Music
297 Fine Arts
882-1202
cell 489-7529