[pianotech] New Asian piano that will not hold a tuning

[pmc033 at earthlink.net]

Hi, David:
	You didn't mention what the environment of the piano is.  Is this an
institution, or a home?  Heating duct under the piano?  Damage?  Direct
sunlight?  Somebody secretly using it for tuning practice?  Here in San
Diego, basically the same climate as LA, most folks tune once a year.  Even
in a year, such changes would be unusual.  
	As far as structural changes, I'd look and see how the plate flange and
block are fitted.  Is there a large gap in there that indicates that the
pinblock isn't tight against the flange?  
	80-90 cents flat in the treble is an awful lot in six months, as well as
the other percentages you mentioned.  I would expect some slippage, but
this is a lot overall.  I've tuned Samicks, which we used to sell in the
80's and 90's, that didn't have this much trouble.  Three pitch raises in
less than  a year !  
	Puzzling..

	Paul McCloud
	San Diego


> [Original Message]
> From: David Trasoff <david at davidtrasoff.com>
> To: <pianotech at ptg.org>
> Date: 06/14/2009 2:31:52 PM
> Subject: [pianotech] New Asian piano that will not hold a tuning
>
> I am wondering what ideas or experience people have concerning the  
> possible reasons a new Korean-made piano seems to be incapable of  
> holding pitch. It's a 5'3" Samick-made grand. It was tuned prior to  
> delivery in early September 08 (I assume it was; I didn't do it). When  
> I gave it its post-delivery service in September it had slipped  
> 30-40¢. I pitch-raised and tuned it.
>
> By December the customer was complaining; I made another service call  
> and found the piano again 30-40¢ flat. I again double tuned it (using  
> the RCT pitch raise function) and left it on pitch. I tuned the piano  
> again in the beginning of June and found the bass about 25¢ flat, the  
> midrange from 10-15¢ flat to on pitch, and the high treble 80¢ or more  
> flat! It seems pretty obvious that something is moving around in  
> there, a bad glue joint in the frame? an improperly secured plate?
>
> I don't have the luxury of going back and making measurements or  
> poking around (I'm not being paid to do that), but I'm interested in  
> what other technicians think may be going on with this piano. I've  
> recommended to the store that sold the piano that it be replaced, but  
> I'd like to have some possible technical points regarding the apparent  
> failure in the structure of this piano to discuss.
>
> Thanks,
> David Trasoff
>
> ---
> David Trasoff
> Professional Piano Service
> 4130 Verdugo View Drive
> Los Angeles, CA 90065
> Tel: 323-255-7783
> Fax: 323-313-1519
> david at professionalpianoservice.com
>
>
>
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