[pianotech] Chickering Grand Hammer Flanges

Joseph Garrett joegarrett at earthlink.net
Tue Jul 26 09:25:34 MDT 2011


Ron said: "This will give you the numbers. Sometimes the Internet is
actually good 
for something.
http://www.engineeringtoolbox.com/linear-expansion-coefficients-d_95.html
 
Brass expands more. So as you heat the things up, the steel screws 
should get looser in the brass, then tight again as everything cools. 
I'm not sure it's been satisfactorily determined whether the whole 
annealing process is worth the trouble though."
 
Ron,
Thanks. That does gives some "numbers" to the question. Not sure if the
numbers tell me anything more than brass expands a lot more than steel.<G>
My "gut" tells me to get rid of the flanges, but IF the annealing process
gives them a new life, (which they have had for 100 years now.), it would
be a whole lot less hassle to keep them. Of course, I must think of the
"Long Term" implications as well. Hmmm? I've seen good results with
annealed brass rails. The fellow that does them has done the rails with and
without the screws and plates attached. He hasn't found there to be any
difference, although he did add: "so far".<G> Things to think about for
sure.
Joe


Joe Garrett, R.P.T.
Captain of the Tool Police
Squares R I



More information about the pianotech mailing list

This PTG archive page provided courtesy of Moy Piano Service, LLC