I have six 8mm steel rods that are 300 mm also six woven carbon fiber the same size, also a 8mm threaded rod the same size. I thought it might be interesting to build your version 2 with carbon fiber and plastic bearings. I may do the Z axis different, but not sure yet. Currently the X and Y parts are being printed. I have a recently built Kossel and am printing crazy. I looked at your Cherry Pi versions and picked up some good stuff. I tried putting magnets in 8mm carbon fiber diagonals, but when I added the .002 thick Teflon mouse disk it seemed to loose about half it's attraction force so I'm back to Traxxes and rubber bands for now. It is printing real nice. There is another delta in the works with 2020 extrusions. I ordered a piece of the carbon fiber pattern vinyl, I hadn't seen that before. You mentioned your other hobby is RC Aircraft, so is mine, but it has taken a hit in time spent lately.
Len
Len