Eeenteresting, and great work so far! Happened to stumble on this thread by accident. I've been quietly working on something relatively similar (split matrix) since last year, though it's not close to being ready for the public reveal just yet. Primary inspirations were also dmw's humble hacker, the M15, and the μTron.
It's quite ambitious in scope and complexity, so it has been rather rough going since I essentially had to learn electronics engineering from scratch for most portions of it, wishing I had an EE expert as a friend for help
. Good thing I have a partner for the code bits. I'll finally have the first fruits of my labor today (pcbs from china), so it's getting there slowly but steadily.
On the matter of 1x2 keys though, it's definitely a bit of a problem. I tried removing the spring from one of the switches, but that actually makes it worse as that switch does not bounce back properly anymore. So the least weight possible for actuation on 1x2 keys is 45*2=90 grams by my reckoning, making them fairly beefy even for thumbs/index fingers. The ideal scenario here I think is to get custom springs made that are 20-25 grams, and that way the double keys will be much better to deal with. I wonder if there's anyone on the forums here that knows about custom springs for cherries... *coughhackwheezeeye*sixty*coughhackwheezeeye*