The keyboard is probably the most difficult of all digital group items to restore. Hundreds of parts must be removed. cleaned, or rebuilt. The key plungers must be carefully disassembled and the gold foil that makes the capacitive key 'contact' must be cleaned and remounted to the plunger with new foam. Here are a few photos of the restoration of two of my keyboards. Enjoy.

Plunger Prep

The plunger with attached foam and foil is the main focus of this whole restoration. Look at the photos, unless a keyboard was preserved in some sort of fantastic time capsule, the foam will crumble with great ease. The gold foil must be pulled slowly and carefully from the plunger, taking great care not to tear the foil.  A razor knife is used to scrap the remaining foam from the plunger. The foam clinging to the foil is a little harder to deal with. I have tried numerous ways of cleaning the foil, and the best thing I have found is to just "dust" the foam off the foil with a soft tooth brush. The sticky backing on the foil seems to strengthen the foil pads. Other cleaning methods tried that remove the sticky goo backing altogether, allowed the foil to curl and tear much easier. This is bad. 

A destroyed foil square can be replaced with plain aluminum foil, but this is not preferred. This alters the design from a capacitive keyboard to an electrical contact keyboard, it seems to work fine, but the foil is far less durable, and I suspect that in time, it may lead to more trouble.