Anyone got experience replacing broken wooden keys in uprights?

[lelle]

So I have an old upright which I haven't played on in a couple of years because the wood in a few of the keys has cracked - basically making the "lever" which the key extends into slack instead of transferring the forces to the mechanism that moves the hammer properly. The whole key would need to be replaced to fix this, and I am wondering if this is something that can be done? Is there a "standard" for the shape of the whole wooden structure that makes up the key including what extends into the piano, or is every piano/manufacturer unique?

I have tried gluing the cracks in the keys a couple of times before, but they always end up breaking in the glued seams again. Perhaps it could work with stronger glue?

[themaximillyan]

If the key is cracked near the hole, then it is necessary to glue PVA (various it's modifications). But at the same time use wood clamps here. For a more rigid connection, use a silk thread too. The thread must be wrapped around (3-4) turns of the key, squeezing the key very strongly so that the remaining glue comes out here. Then put it in the clamp there. Wait up to 24 hours for end result. Remove glue from sides of a key use sand paper 600 there.
If during operation the key breaks in half again, then use epoxy glue than. This is almost 100 percent success always.
Good luck,
regards, Max

[quantum]

Had a repair done to my upright a long time ago (no longer have this piano).  The tech glued the key back together.  In addition, he sanded one of the sides down and added a veneer patch for strength.  It was a job that needed to be done in the shop, so the tech took the keys with him and returned them a week later.  It definitely worked, as the repaired keys never gave problems afterwards.

[quantum]

If you want to try a glue repair yourself, I would recommend looking up videos on woodworking repair and  glue up to get an idea of what is needed to achieve a good repair.

Here is one:

[themaximillyan]

If the key is cracked near the hole, then it is necessary to glue PVA (various it's modifications). But at the same time use wood clamps here. For a more rigid connection, use a silk thread too. The thread must be wrapped around (3-4) turns of the key, squeezing the key very strongly so that the remaining glue comes out here. Then put it in the clamp there. Wait up to 24 hours for end result. Remove glue from sides of a key use sand paper 600 there.
If during operation the key breaks in half again, then use epoxy glue than. This is almost 100 percent success always.
Good luck,
regards, Max

In some cases, the key may break across the entire opening. In such situations, it is necessary to apply shimming on the edges using veneer made from hard woods like oak or ash. Here is an additional step to include in the instructions:

Take a piece of veneer from a hard wood such as oak or ash. Make sure it is slightly larger than the cracked area of the key.

Apply a small amount of PVA glue to one side of the veneer.

Place the glue side of the veneer onto the cracked area, making sure it aligns properly.

Use wood clamps to hold the veneer in place firmly. Apply even pressure to ensure a strong bond.

Leave the clamps in place for up to 24 hours to allow the glue to set and the repair to become solid.

[lelle]

Thank you both for the detailed info. I might try my hand at this.