I got myself the mini version of this keyboard but it's not in the language I want, so I started building some custom key caps.

You'll only find the "blank" version of the keycaps for now but I'm working on versions with very thin letters that let the backlight through. In the screenshots you'll see "Ö" letter as work in progress. Feel free to remix your own!

The caps I've designed are tested on the mini version of the keyboard below but I expect they will work on the full sized version as well.

https://www.logitech.com/en-eu/shop/p/mx-mechanical

I've printed the blank key caps with the default 0.4 mm nozzle, no supports, 0.08 mm layer height and they came out pretty good using eSUN PLA+ on a P1P. Refer to the picture for how the model is oriented for print.

For the 'work in progress' version with letters I have to switch to a 0.2 mm nozzle and 0.06 mm layer height to get the results I want, but that is a story for the future.

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update ~6 months later: I've completed work on a few letters (Ö, Ü, Ğ, Ç, İ, Ş) and volume buttons. I've attached the Autodesk Fusion export (.f3d) in a zip file (and posted a remix here) if you want to use them or modify the keycaps to your needs. To print the keycaps with letters (Ö, Ç, etc.) you need a 0.2 mm nozzle (not layer height, but the physical nozzle). Alternatively you can modify the letters to be a bit thicker and print with 0.4 mm nozzle as well, but it'll let less light through. This is how it looks;