Ridiculous Pitch Raise! reply

[pianoman]

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> From: LTpianoman@aol.com
> To: pianotech@ptg.org
> Subject: Ridiculous Pitch Raise!
> Date: Friday, August 29, 1997 10:53 PM
> 
> Dear List,
> With the kind help of the List I recently performed my first valid pitch
> raise on an old but sound Hobart M. Cable upright. I did a pitch raise on
a
> piano before I really knew very much about tuning and I was unaware that
it
> was a pitch-raise...I just thought, "gee, this piano is really flat!",
and
> you can imagine what a disaster that was, treating it like a fine tuning
and
> going crazy. Well,  now I'm confronted with an 1898 Sohmer upright
"grand"
> that I am re-conditioning which is 139 cents flat. The plate is good, all
> bolts are tight and it is a solid piano. I have heard from some techs
that
> older Sohmers do not take too well to pitch raises. (?)  Also, 435-A is
> factory-enscribed on the plate.  My question is, if this is done properly
and
> with all precautions taken, would it be adviseable to take it up to 440
or
> should I only go up to 435 as it came from the factory? Any input is
> appreciated. Thank you in advance.
> 
> P.S.-The Hobart came out very stable and right on 440 in 3 passes with
only 2
> broken bass strings...and it sold for $1100 in a few days. My first major
> accomplishment!!  (it was a candidate for the dumpster and it transformed
> into a beautiful instrument).
> 
> Larry Trischetta
> Scranton,Pa. Pocono Chapter
> Randy Potter Student
> LTpianoman@aol.com 
Dear Larry,
On the Sohmer here is how I would proceed.
Pass #1 If you use an SAT bring it up to -20c the first pass, this would be
the A-435.
Pass #2.  If needed, use the pitch raising program in the SAT to -20c.
Pass #3 Fine tune.

If you use a fork bring it up the first time to 5 BPS flat to the fork. 
Next pass overshoot by about 1/3 the amount it is flat.

Pre-Passes.   Lube under bearing points, pressure bars, upper offset pins.
Go slow and carefully and confidently.  If alll this goes well I would
consider bringing it up to A-440 the next time you tune it which ought to
be in a bout 2 weeks.
James Grebe
RPT from St. Louis
pianoman@inlink.com