yamaha butt flange repair

[TOM DRISCOLL]

  Subject: yamaha butt flange repair


          Hi Listers,
          I need some advice on a Yamaha hammer butt flange replacement I just did.
          Many of the original flanges in the upper treble were so closely fitted I had to pry them loose from the rail.
          No space between. 
          Also, the hammer butt would not line up as it had been when the set screw on the plate was tightened. It tweaked them off to the side, and they just didn't feel as secure. They are not spaced to the strings properly now, and it is going to be a problem.
          I used flanges from Pianotec, pins are the same size as originals.
          The reason for the job was the silk cords being broken.
          I could use some help...
          Rick Ucci/Ucci Piano  
              
          Rick,
              For the next job, please consider replacing the cords with the flanges in place. I've done at least 25 of these jobs and have a technique listed in the archives. Jon Page also has a posting in the archives detailing his very similar method.Two hours start to finish.
              Tom Driscoll
              
              P.S. searched the arhives and found my post from may 2002 with some minor changes.
              This is a favorite job for me as the broken cords open the door for action work- regulation that the client might not otherwise consider.
          These piano's are often U3's or their cousins and are a pleasure to work on and will give you  an opportunity to voice these often harsh sounding hammers--See the recent thread on steam voicing.
              One last point-- Removing the old flanges will give you 88 chances to cross thread the flange screw in the alum. rail. Even with  the technique of turning the screw anti clockwise until it clicks , I find these rails to be very unforgiving --

              From 2002
           
I've done many of these jobs and have posted a method for
replacement of the cords in the past. With input from a tech in Japan,
(Sorry, but his name escapes me now) I refined my approach so at the
risk of some redundancy here goes. First, we are assuming that the
pinning is solid, the flanges are well traveled, and the hammers are not
worn past reshaping. These pianos are usually less than 20 years old and
if not in a school situation, I've found them to meet these criteria.
	 I first tighten all screws and space hammers. Reshape hammers
and blow out all debris. Remove the hammer rest rail--easily done in
this action by unscrewing the hangers from the rail. Next Loosen the
butt plate screws and hang the whole butt-hammer assembly from the
bridle straps without disconnecting them from the bridle wire.(That was
the tip from our Japanese friend ) Now the flanges are exposed for
removing and replacing the cords. I put a small amount of ca glue
solvent .    Addendum 2006 --I now use acetone and no the acetone does not affect the flange bushings-action centers    on the slots and then immediately clean out the old cord and
slot with the chisel point of a small spade drill bit.( By hand -not
chucked in the drill!)  You may have to reapply the solvent as you go
and I suspect acetone is the the operative chemical at work here.    Addendum 2006--I now finish cleaning the slots with a small brass brush ,then dry with compressed air 
	Now for the cords. If this is not a gray market piano you can
get the cord from Yamaha wrapped around a small cardboard tube. If not
available wrap some silk cord ( avail. From Schaff ) Addendum 2006 (We could fill a book with list suggestions for cord material since this post)around an old #88
key top and slice down the middle. Either way, but the idea is to get 88
cords cut to exact length. Now glue one side in the slot -I use
titebond- a small amount -and press the cord in the slot with a small
screw driver lining up the end of the cord with the line in the flange.
By the time you get to the end the glue will be set. Go back and glue
the other side. Reinstall the hammer-butt assemblies, put the springs in
the cords, reinstall the rest rail and your done . Two hours max and
less with practice.  
	The advantage over replacing the flanges is not only time, but
it is difficult to travel the new flanges with the dampers in the way,
your spacing will not change and the old flanges are already
dimensionally more stable @ the screw and will not need retightening as
soon. 
	Tell me this is a worn action with loose pinning and flange
replacement is the best way. Also if this is an action without butt
plates and the flange is pinned to the butt in my opinion it's less
clear which method is best. I've done about quite a few of these and
almost all have the butt plate style.  
	` Tom Driscoll



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