yamaha butts

[Paul McCloud]

I just finished doing a set of these on a U1.  It took me about 3
hours.  I didn't replace the flanges, but did the cord replacement.
Some of the flanges in Yamahas have the screw/plate arrangement so you
can remove the hammer/butt from the flange easily- this was the case for
me.  I removed the hammer rest rail, undid the bridle tapes and removed
the hammers from a section of the action.  I used a coping saw blade to
scrape out the grooves.  I used CA glue kicker brushed into the grooves,
put the cord into the groove, and brushed CA glue over the top of the
cord.  You can get this CA glue from Locktite which has a brush in the
cap.  It's meant for joining wood.  The glue instantly dries.  Small
downside is the the kicker starts to gel the glue after a while in the
brush.  Use a 5/8" dowel and wrap the cord around it as closely as you
can, the slice across the wrapped cord to make loops just the right
size.
    Since you aren't changing the flanges, there's no worry about
whether your string grooves line up in your hammers. The hammers go
right back where they were.  You could file them if you want, and use
Barrie's method of clamping them together and gang filing them so
they're square.
    If you have to repin with the old style of flange (no screw/plate),
you would have to remove the assembly and put in a vise to redo the
cords.  That took me about 6 hours last time.
    Just my way.
    Paul McCloud
    San Diego