Retrofit Preonic Ergonomic Keycaps

Update

Slowly adding better versions of the STL files as they render. each of these is modified from the original version to be a little less aggressively curved and much shorter:

1. sa_ergo-all_in_one_fdm.stl: uses stem supports that extend throughout the print, making it sturdier while printing and less prone to failure. slice between keys to make separate chunks if you have a small bed.
2. sa_ergo-upside_down.stl: has all keys sitting on their dish; prints the stems much more consistently, but not the keytops. You can use the quality sliders in prusa slicer to get a better surface. Rounding errors mean not all keycaps are flush with the bed, but you'll need to print with support anyways.

Couple people asked for the stl so I thought I'd share. These are "ergonomic" retrofit keycaps for a Preonic.

Ergonomic keyboards like the kinesis advantage, dactyl, etc. have "key wells" - semi-circular indentations filled with keyswitches - and column offsets in order to minimize finger travel. In order to wire these keywells up, the Kinesis relies on flexible PCBs while the dactyl is just hand-wired. I created these fully sculpted keycaps with columnular staggering to approximate the feeling of one of these ergonomic keyboards on a flat-PCB keyboard.

The set may be difficult to print all in one go and the sculpting is aggressive to say the least. If you're looking to print these I recommend you check out the script that generated these files and tweak it to your liking: https://github.com/rsheldiii/KeyV2/blob/master/examples/sa_ergo.scad you'll need to download the entire repository but then you can open just this file in OpenSCAD. I'd recommend less stagger and a larger full sculpt radius, as well as decreasing the height of the keycaps as much as you can before the lowest keys start losing their stems. I also recommend adding on stem support, or using the upside_down() helper to print the whole set upside down. The letters are included, but you'll need to adjust their z height for multimaterial printing, as I was just using them in a render.