Yamaha repair

[Tom Driscoll]

From: "David Love" <davidlovepianos@earthlink.net>
To: "Pianotech" <pianotech@ptg.org>
Sent: Thursday, February 05, 2004 3:17 PM
Subject: Yamaha repair


> I've got customer with a Yamaha console that needs all the thread that
> holds the hammer return spring replaced (they're all breaking).   I'm
open
> to suggestions about an expeditious way to go about this.
>
> David Love
> davidlovepianos@earthlink.net
>

	David,
	I posted this method for this repair a few years ago. I've
replaced flanges, but find  cord replacement with existing flanges to be
my preferred method for the reasons mentioned below.
	Tom Driscoll
			
>From the archives with editing:
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.
> With the action in the piano I space hammers tightening the hammer
flange screws. 
	Now with the action on the bench and in the cradle,I  tighten
all remaining screws, 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 acetone
> 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.
> Finish the slot cleanout with a small brass suede brush, and
compressed air or vac.
	(I found that the action centers are unchanged by any acetone
that migrates to the bushing)
> 	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) around an old #88
> key top and slice down the middle. Either way works, 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 all 88 done 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.
> hammer spacing will not change, the old flanges are already
> Dimensionally stable @ the screw and will not need retightening as
> soon. 
> 	If this is a worn action with loose pinning then 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
> 
>