Gluing wippen

[Billbrpt@AOL.COM]

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In a message dated 1/12/01 8:07:53 AM Central Standard Time,=20
istuner@islandia.is (Kristinn Leifsson)
 writes:


> I=B4m trying to fix a broken wippen from a Wagner upright.
> The problem is that there is no jack flange, but the center pin goes=20
> through a hole in the wippen "proper", so I hesitate to find a replacement=
=20
> instead of fixing it, since this is not very common in pianos around here.
> It=B4s been glued before, but it broke again.  However I don=B4t think it=20=
was=20
> glued well enough so I=B4d like to try it myself (the pieces fit pretty we=
ll=20
> together)
>=20
> What interesting methods might be hidden there inside your brains?
> Wasn=B4t it Susan Kline that had something involving two types of glue.
> Could you explain thoroughly which glues ya=B4ll have in mind, seeing as=20
> trademarks are variable?
>=20
>=20

It's not clear in your post just how the wippen is broken.  I'm thinking tha=
t=20
the piece with the hole in it for the center pin is split.  You could use=20
either slow setting CA glue or Epoxy.  If you place a small center pin in th=
e=20
hole while you have glued and clamped the piece together, when the glue is=20
cured, you can remove that center pin and have a nice, tight hole for the ne=
w=20
one.  You would sand or trim off any excess glue residue and if your hole is=
=20
a bit too small, you can ream it to a size that will work.

The idea of using 2 glues is this:  CA glue sets slowly unless you use a=20
catalyst/accelerator.  The usual accelerator is a toxic solvent called 1-1-1=
=20
Triclorethylene.  It has a pungent odor and many people say that continuous=20
exposure to it may cause serious health problems in the future.  On top of=20
that, it can cause the CA glue to cure so quickly that it's strength as a=20
bonding material is weakened.  Indeed, it "fries" and bubbles up and can end=
=20
up being soft and fluffy like Styrofoam when cured rather than turning into=20=
a=20
hard, plastic like material.

So, there are other materials which can cause the glue to cure more quickly.=
 =20
Baking Soda is one.  Just a little moisture is another.  White or yellow glu=
e=20
has both moisture and some organic material (particularly if it is a milk=20
based glue) that will react with the CA glue.  The idea is to apply the whit=
e=20
glue to one surface and the CA glue to the other, then assemble and clamp=20
quickly.  It will set within a few minutes and probably be cured in an hour=20
or so.

Finally, if this piece ends up still being a little weak, could you trade it=
=20
with a wippen from the high treble?  Presumably, moving that wippen to the=20
last or nearly last note of the piano where it would be used infrequently an=
d=20
replacing it with a stronger part would avoid any future failure.  If the=20
wippen has a damper spoon on it, however, you'd have to extract the spoon an=
d=20
drill a hole in the high treble wippen for it.  You could also use CA glue t=
o=20
secure the spoon in the new wippen.  Put CA glue in the hole and dip the=20
spoon in white glue and insert.  It will cure within minutes.

Bill Bremmer RPT
Madison, Wisconsin

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