Another month, another update!
TL;DR: Boards arrived, lots of soldering to do, software is ready
Despite being a bit busy I managed to get the daemon software where I can comfortably release it.
Plug&play works with the thermal printer cart, just slot it in and send to /tmp/DEVTERM_PRINTER_IN immediately!
Check out the code here.
What’s left to do is pretty much soldering the through hole components as well as the TVS diodes.
The latter is a screw-up on my part which could’ve been avoided, but rest assured I’ll solder all 153 of them.
Another mistake I made is ordering the wrong kind of fan from Alibaba.
I double checked the dimensional drawing, but the fans I received had the mounting holes somewhere else entirely. I should have communicated that I need the exact fan as described, oh well.
That leaves 4 options:
- I’ll try again ordering fans and wait 3 weeks (unacceptable)
- the user has to transfer the stock fan to the board
- gluing it down
- mounting it with a small 3D printed part
The following is a mockup of the 4th option.
I feel like this is the only way to go.
Also these fans have a third unwired pin which is a tachometer signal.
Tough I won’t take even more time soldering on a third wire, I want this to be finished too some day 
Lastly about the 3D printed parts, my kitted out Ender 3 is nice and all, but it is on its last legs.
This is why I bought myself a new Prusa Mk4 which will arrive next week,
hopefully to make the 3D printed parts in the kits of acceptable quality.
What I am stuck at is writing the manuals for self-assembly.
I question if it is even needed and if I should spend that energy somewhere else.