Yamaha Jack issue

[pianolover 88]

Just so happens the piano in question in my case is *also* and M500. Well, after putting action back in and checking LM and everything else I could think of, the problem seemed to have "lessened" somewhat, but some jacks still hang up for no apparent reason. I did pretty much everything you did as well and now I'm thinking the only thing left is to replace ALL the jack springs with a more heavy duty, stronger spring to insure full return. I would rather do this then stretch out the existing springs. I realize that this will make the touch heavier to some degree, and explained this to the customer. Although I could find some jacks still hanging up, when she sat down and played she was happy with the results and , and didn't seem to encounter any problems...yet. 

Terry Peterson

From: atuneforyou at hotmail.com
To: pianotech at ptg.org
Subject: Yamaha Jack issue
Date: Wed, 19 Mar 2008 09:28:40 -0700








Terry,
 
I had the same problem with an M 500 a couple of weeks ago. I have had similar problems/ issues with consoles or uprights in the past usually in the high treble were the hammers are lighter. I always considered this a key weighting issue. This particular instance was at B 1. Checked all friction, whippen, jack and hammer. All good, in fact if anything they were pinned too loose. Tried more lost motion, lubricated jack, teflon on butt leather. Increased key dip. Increased jack spring tension. Nothing worked. Well in the end, with the damper pedal depressed and rapidly playing the note it would fail after about twenty repetitions. Under normal playing, if the jack failed to return under the hammer butt, as soon as you release the damper pedal the jack would slip back under the hammer butt. So I told the client "that's as good as it gets", and called it a day. Driving away, I tried to rationalize that it was an unexplained phenomenon. I could not escape the feeling of failure to solve the problem.

 

One thing that was mentioned by someone I can't remember who. What would the key bed have to do with this phenomenon?  
 
Steve Blasyak
Orange County Ca.
 
Pura Vida


Need to know the score, the latest news, or you need your Hotmail®-get your "fix". Check it out.

_________________________________________________________________
Helping your favorite cause is as easy as instant messaging. You IM, we give.
http://im.live.com/Messenger/IM/Home/?source=text_hotmail_join
-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/pianotech.php/attachments/20080319/76c1c57c/attachment.html