Pianos can be beautiful pieces of furniture to display in your house, though not all pianos play very well. Converting an old piano to a keyboard is fairly simple and it's a good way to have the look of a real piano without ever having to worry about tuning or piano maintenance. Most 88-key keyboards will fit into the soundboard of an old player piano, allowing the performer to enjoy the look of playing on a real piano, versus a keyboard on a stand.
Make sure your keyboard fits into the piano casing by measuring the base of the keyboard and the base of the piano's keypad -- what the keys lay on. The best way to check if it fits is to manually place your keyboard in the space. Unscrew the boards that fit over the keys -- screws are on the sides -- to have more room to work.
Gut the old piano by loosening all the strings and taking them out one at a time. You'll need a piano wrench to unscrew the tuning pegs. Turn counterclockwise to loosen. This will take a long time, but you have to take the strings off first for safety reasons. When taught, piano strings contain tons of pressure. If a string breaks, it can snap back with enough force to kill someone. Take the strings off before you try to take the soundboard out.
Unscrew the soundboard once you have all the strings off. The main screws are generally located on all four corners and two in the middle of the soundboard. To better get to the soundboard, take off the board above the foot pedals. This will allow you more room to work inside. Once the screws are out, you can lift the soundboard out of the piano. Be careful: The soundboard is very heavy.
Take the keys off. They will be loose now and can be lifted away. This will expose the baseboard where you will place your keyboard.
Place strips of Velcro across the baseboard and on the bottom of your keyboard. This will keep your keyboard in place and steady when its being played. Don't use glue, you'll damage your keyboard if you ever need to take it out again.
Drill a hole into the back side of the piano to fit your power cable through.
Take out the pedals by unscrewing them. They should lift right out. The inside of the piano should now be completely empty. Attach Velcro to the bottom of your foot pedal and place where the old original pedals used to be.
Measure the distance between the sides of the piano and the new foot pedal. Take a pencil and mark off measurements on the board that fits above the pedals and cut out a square 4-inch section for your new foot pedal to fit through. Once finished, attach the board back into place and make sure the pedal fits through properly.
Plug in your keyboard and begin playing. You may have to access the power button by lifting the top of the piano and reaching underneath.
You can still use the original foot pedal by gutting your electric pedal and soldering the wires to the original piece. If you're going to put a keyboard in an old piano, use an 88-key keyboard that has weighted keys. This will make it feel more like a real piano.
Beware of the tension in the strings when taking the piano apart. Always loosen and take out the strings before taking out the soundboard. The taught strings have enough pressure in them to seriously injure and even kill someone if they break when taught.