[pianotech] Pitch Change, etc.

[tnrwim at aol.com]

Wim,
Think about that statement. Doing that huge pitchraise is going to put the entire structure under a greater load...including the plate! So, measuring the distance from the plate to the soundboard will not be an accurate place to measure! You'll need to have an apparatus that is firmly fixed to the floor to take the measurements. Then, the movements you record will have more significance. Such a device would/could measure other parts to see how much they are moving as well. (which is part of the whole picture, IMHO.<G>)
Joe

Joe

I thought about that. But what I was mainly interested in is how much the bridge drops right in the middle of the soundboard, where there the upper bass strut crosses the treble bridge. Yes, everything moves, but not as much as the soundboard. The plate will stay pretty steady since there is a nose bolt about 6 inches from the edge of the plate. That nose bolt is attached to the plate and to one of the beams under the piano. So there isn't going to be as much movement as the soundboard. 

In any case, I didn't get to take the measurement. Maybe next time. 
Wim






-----Original Message-----
From: Joseph Garrett <joegarrett at earthlink.net>
To: pianotech <pianotech at ptg.org>
Sent: Mon, Apr 5, 2010 7:05 pm
Subject: [pianotech] Pitch Change, etc.



Wim said: " should have measure the distance between the soundboard and the plate before I started, but I wasn't thinking about this subject until after I got started. 
 
Wim,
Think about that statement. Doing that huge pitchraise is going to put the entire structure under a greater load...including the plate! So, measuring the distance from the plate to the soundboard will not be an accurate place to measure! You'll need to have an apparatus that is firmly fixed to the floor to take the measurements. Then, the movements you record will have more significance. Such a device would/could measure other parts to see how much they are moving as well. (which is part of the whole picture, IMHO.<G>)
Joe
 
 
Joe Garrett, R.P.T. (Oregon)
Captain, Tool Police
Squares R I
 
 


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://ptg.org/pipermail/pianotech.php/attachments/20100406/173494a7/attachment.htm>