[pianotech] Moving the wippen heal, (HEEL!)

[Joseph Garrett]

David Love said: "Subject: [pianotech] moving the wippen heal
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Caution, this has to do with pianos. 
 
Had to relocate a set of wippen heals after moving the capstan. Often I
just cover the entire heal with felt if there's a problem with the new
capstan position contacting the wooden edges of the heal. In this case I
didn't want to do that so I wanted to figure out a way to remove the heal
and relocate it. I could have just trimmed the entire heel off with a
bandsaw and then bought a new set of heals but preferred to try and salvage
what was there. In this case I needed a 4 mm move. I marked and drew a
line that distance from the original heals first for indexing the gluing of
relocated heal, you can see that a bit in the first photo. Then to remove
the heal you first have to clamp the wippen in a vice. I used some two
sided tape to attach these wooden strips so I could clamp that lower part of
the wippen without interference from the wider flanges and posts (second
photo). To remove them I took a sharp chisel and ran it under the thin glue
bead at the edges--kind of rubbery stuff (third photo). Then with a very
light tap on both sides the heal it comes right off. Safest to tap very
lightly just until you hear the joint break on one side and then switch to
the other side. Didn't have any tear out on any of the removals as these
are mostly glued at the edges. After the heal is removed I cut off the
nipple with a band saw--make sure you don't leave a high spot there, a bit
low is ok since the heal will be held in place by the outer portion. A few
swipes over a sheet of sandpaper to clean it up and then glued it back in
place as pictured in the first photo. I found the easiest way to work was
to flip the stack upside down and rotate it to a 45 degree angle (first
picture kind of gives you an idea) with the flange screws up so you could
just work across one at a time. Use a short block on the end of the stack
to keep it in place. Takes a couple of hours. 
 
BTW this was a early accelerated action Steinway (as you can tell probably).
A move to a 17 mm knuckle still left the ratio at about 6.1. I wanted
something around 5.5"
 
David,
It would have been appropriate to say that the Wippens you are working with
are Renner type.<G> I have done the same job, but I did it a bit
different...same basic result. 
My method: I found that the glue used to attach the Heels, is easily
softened with heat! So, I rigged a piece of Brass in a "U" fashion and
attached it to a small soldering w/a rheostat in line to control the heat.
The "U" slides down over the Heel and heats up the heel and the glue. About
1 minute was sufficient to do the job for each of them. Grasping the Heel
with wide jawed Duck Billed Pliers, a slight twisting motion and off it
came. I then drilled a new hole for the Heel Stem, (for lack of a better
term), (Also, I made a jig to accurately hold the wippen in exactly the
same position w/the cross vise I use on my drill press), in the new
location. Then Hot Hide Glued the bunch all in one swell foop.<G> A bit of
info, that I've gleaned regarding those Renner wippen feet/heels: The felt
is NOT TAUT in the current "mortise"! This creates a massive amount of felt
slop, which causes massive amounts of  FRICTION! Some of it is due to the
Cheap/Course Action Cloth they use. My solution is to remove the "ears" of
the Mortise and put some good Action Cloth, of the appropriate dimension
back on, being sure to STRETCH the Felt for a TIGHT fit. Once that is done,
the action friction drops off markedly! Try it sometime, in an experiment,
you'll be amazed.<G> I first discovered this on a fairly new M & H. Go
figger. Another solution, is to IRON the crap out of the felt to make it
harder and  to make it shink. I use a Hammer Iron for that job. Then
impregnate powdered teflon and IRON again. That will also help the friction
problems of that wippen.
Hope that helps. Ah, at last PIANO Topics.<G>
Joe


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