|Replacing piano keytops.
Replacing old keytops with the new molded plastic tops (parts page) will make your keyboard look brand new and is a relatively easy procedure, with only minimal (if any) reshaping needed. You'll need a single edge razor blade or a thin bladed knife, and some "contact cement" or PCV glue (other adhesives are also useful for this purpose, but these glues are fast, strong and do not require clamping as many other glues do. Since clamping is not required you are able to replace keytops without removing the keys from the piano, a real advantage. Contact cement and PCV glue are available at most hardware stores).
The most difficult part of the job (aside from removing the cabinet parts) is getting the old plastic or ivory off the keys without damaging the wood. The beauty of these molded tops, however, is that they are extra thick and will cover the keywood even if it is damaged.
First, open the piano top and front piece and remove the fallboard (the cabinet part that drops down over the keys) and any other cabinet part that restricts your access to the top and front of the keys. The exact procedure for this will depend on your piano model, but a little observation should show you what you need do (go here for an illustrated discussion of opening vertical pianos, or here if you have a grand). You'll need a screwdriver, of course (probably both a regular and phillips head) some medium sandpaper, and a small file.
After you remove the fallboard you may also need to remove the keyslip (the board running across the piano in front of the keys) IF you are using new keytops with fronts. On grand pianos this is relatively easy if you don't mind getting on the floor under the piano. To remove the keyslip you'll need to remove the endblocks (the large flat blocks of wood at each end of the keyboard). They are usually held by large wing nuts located under the keybed on each end (on newer pianos) or by large wood screws on older instruments. After the endlocks have been removed, the keyslip either simply lifts up off its guide pins, or itself is attached with several wood screws under the keybed as shown in the drawing.
On vertical pianos, the keyslip may also be held by screws under the keybed, though more often than not it is part of the casework and cannot easily be removed. In this case it may be necessary to remove the key from the piano to recover the fronts.
To remove a key from verticals, remove the fallboard and the key retaining board (the long slip of wood crossing the keys at about their mid-point. It is held by screws at either end, and perhaps a slotted nut near the middle). Lift the key up and off its guide pins and out of the piano (go here for a picture of how keys fit on their pins). Note: If you have a very old upright piano, check to make sure the bridle tapes that connect the lower and upper action parts, are not broken. Broken straps will create problems when replacing keys. Either get a book on piano repair, or call the tuner to replace the straps. Unfortunately, removing keys from spinets or grands is a much more difficult process than for uprights or consoles, so you'll probably have to work with them still in the piano.
In any case, proceed as follows:
(1.) Using a thin blade knife or razor blade, carefully loosen the old keytop by working the blade between the wood and the key material. If your old keys are real ivory, they will be in two pieces, a head piece and a tail piece. They were probably attached by cloth wafers and may simply pop off with relative ease (don't count on it), though they may also break into pieces. Plastic tops may offer more resistance. Work carefully and try not to damage the key wood. If you are using the new type with fronts, also remove the old key material on the front of the key. If using the type without fronts, carefully scrap the dirt and crap off the front piece with the razor blade or fine steel wool to clean it up. If you have trouble removing the tops, some technicians recommend loosening the glue by briefly applying a heating iron on them. But be sure to place a very slightly damp cloth over the key first or you can end up with a very messy iron. Apply the iron for only 10 or 15 seconds to keep from melting plastic. Anyway you go about it you may damage the tops, but since you are replacing them it's a moot point. There are several videos of removing old key tops on YouTube, so searching for them before you start may help.
(2.) Once the old keytop is removed, use the razor blade and sandpaper to remove any remains of the old wafers or glue.
(3.) Apply a thin layer of contact cement to both the top of the key and the bottom of the new piece (note that the new keytops are labeled A, B, C, D, etc. as to which key they fit...they are not interchangeable even if they appear to be). Allow the glue to become tacky, according to the instructions on the glue container (if using PVC glue there is no need to wait for it to become tacky).
(4.) Once the glue has become tacky, carefully align the keytop to the key, making sure the edges are even and the keytop centered. Do not press the top down until you are certain it is straight. Sight down the sides of the key to check alignment. When you are sure the keytop is centered, press it firmly to the key and hold it tight for about a minute or so, or wrap it tightly with string to hold the top down. Be certain the top is aligned correctly...once it is pressed into place it is very difficult to realign it. If you goof the alignment, quickly pry the keytop off, clean the glue from both parts and try again.
(5.) If the edges of the new top extend beyond the wood, carefully file them flush to the wood (this is usually not necessary since the new tops are designed to fit most keys, but sometimes the fit is not perfect. Fortunately this plastic files easily with any good wood file). Also note that, since these new molded keytops are thicker than the old ivory or plastic, it may be necessary in rare cases to shim the fallboard with thin cardboard shims to allow it to close correctly (place the shims under the fallboard hinges, or under the end blocks on old grands).
The procedure for replacing sharps is the same. If your new sharps are real ebony wood, plain old carpenter's glue such as Elmer's will work ok in a pinch, but you'll need to press the key firmly in place for ten minutes or so to allow the glue to set. Contact cement is easier with any key material. (DO NOT use wet, slow drying glues such as Elmer's if you are replacing an old ivory keytop back onto the key as the moisture will cause the ivory to warp). If you have any problems fitting the keytops, send me an e-mail or call and I'll help if I can.|