I thought I'd report on the status of my offer of two free keyboards. Curiously, I only received three keyboard requests. I meant to impose a barrier to entry, but maybe not that high a barrier!
I decided not to choose, but instead to make three keyboards. I have ordered and received the electronic parts. I've decided that while I might be able to produce keyboards from the hand photocopies the winners sent in, it's too uncertain a process. Still tinkering with the design, but I think I've settled more on a "kit" for a keyboard.
The trouble with the Chordite is that it really needs to fit your hand. And yet, as a portable device, it needs to be sturdy. Adjustable yet fixed. Malleable yet unchanging. This is not a new problem for people to have faced. Screws, nuts and bolts, glue, clay, plaster, wood, plastic, metal, and rock are all substances which can be changed and yet which are sturdy.
Hands are variable in two ways that matter: in finger length and spacing and in palm width. The chordite needs to be stretchy in both those dimensions, and yet, if you drop it, it shouldn't fall into pieces. It needs to be lightweight so that you can carry it. In order to make all this work, I think that I'll put the switches on little PC boards interconnected with 18 gauge copper wires, covered with a layer of polycapralone. The copper for stiffness, and the polycapralone for sturdiness.
I've done some testing, and an ordinary hair dryer puts out enough heat to soften a fairly thick layer of polycapralone. Once softened, the keys can be moved around, with the copper wire keeping the keys in position while the polycapralone is soft.
Once I've made the PC board with the bluetooth module at the heart of this keyboard, I'll ship these to the lucky winners. We'll see what they have to say. If it's not good, then back to the drawing board.