The keyboard is a quite large assembly group consisting of almost 900 parts. The most laborious part is the ”stairs“ in which the keys can be found. The original has a bakelite press part which I could not press due to its large size. Therefore I used epoxy resin to cast them. Before I could do so I had to make an exact negative mould from steel that contained moveable pins to mark future drill holes.
Before casting the mould was coated with a special release agent. After that, the castings had to be reworked, of course.
The making of the keys is very time-consuming because each of them has a a face, a slit and three tiny drill holes. For these a small drilling jig was built so that the holes could be placed exactly. That was really helpful, yet drilling such tiny holes is not real fun.
The contact sets consist of different small plates that were punched out, pressed into shape and later partly nickel plated. Three threads were cut in the angle brackets before trimming them. After assembly each contact set was adjusted to a certain contact gap.
Here you can find a short video of the contact action.