Polargraph Gondola see-through
I have taken the design for Polargraph gondola and have remixed and re-created it so it's possible to see through it to see the pen and it drawing.
You will need to print:
1 x gondola
2 x hubring (NOTE: I had to print the hubring at 103% scale or else it would be too tight)
2 x hubspacer (optional)
1 x hubcap (optional, I just used a zip tie)
The fastening mechanism uses an M4 screw and a threaded insert, you have to heat and melt it into the plastic.
Source code and instructions to build the full Polargraph can be here: https://github.com/john4242/grbl-polargraph