Repairing Keys with Broken Plastic Pieces
On older harmoniums, the white or 'pearloid' plastic pieces on a key can come off because the glue has dried out. This can happen on any harmonium, but I've seen it mostly on older Calcutta harmoniums. This section shows how to repair these...assuming you haven't lost the pieces!
First, remove the "H" shaped board which is covering the keyboard.
The image on the right shows one of the screws which have to be removed. Some harmoniums have two screws here. Remove them both. There is also a screw or screws to remove on the left side of the keyboard.
Once these are removed you can lift up that whole board to get full access to the keyboard.
There maybe be a nail one each side which secure the assembly to the case. Just carefully lift the whole piece straight up and the nail will lift out of the case.
The next task is to remove the bad key from the keyboard. Use a small screwdriver to gently pry the key straight up and out of the channel that is holding it.
Once the key is free of the keyboard, you need to remove the glue from the key top and the front. Use sandpaper or a file to remove the glue. You want to get to bare wood as best you can. You should also sand the glue from the bottom of the key top and/or key front to insure good contact See Fig 1.
Using a good quality wood glue (like 'Titebond'), apply a small amount of glue on the top of the key and if needed, the key front. Spread it into a thin layer. You don't need to use a lot of glue, just make sure it covers the surface where the plastic will be attached.
Place the plastic piece on the key and move it around a bit to spread the glue evenly. Align it on the key so it is in the same position as the other keys. You might remove another white (or black) key to help you align the one you are gluing.
If you have clamps, you can use them to secure the plastic to the key, or use rubber bands as the Fig 2 below shows.
For a black key (Figs 4 and 5), it is harder to align the top with the key, so I suggest removing a good key as a guide for placing the key top.
Let the key dry overnight then remove the clamps or rubber bands.
Fig 1
Fig 2
Fig 3
White Key with Missing Key Caps
Key caps glued and drying
Repaired White Key
Fig 4
Fig 5
Black Key No Top
