I really like how you did the blade.
I had massive problems getting mine done. I tried to bend it into shape with a vice and wood blocks :-/
I thought about using a tube, but I am not sure I could cut it clean enough with my jigsaw
Might have to build a guide for the saw? That could work...
What diameter does the tube for the blade have?
I thought something in the 100mm region would look fine, but yours seem a bit smaller? This would make it a bit cheaper...
How do you mount the blade to the rails?
I have the silly(?) problem that my screw heads are sticking out of the rounded blade surface. It seems you are mounting from the backside with tapped/threaded holes in the the blade. You'll then grind/file/cut the protruding screws to sit flush with the blade?
I've thought about doing something like that when I take apart, paint and reassemble my grader. Not sure I can do this well enough with my tools, willing to try, though =)
The outer black dots in your photo look as if they are screw heads, what are you going to do about that?
Also, your sliding mechanism seems to be aluminium on aluminium - have you thought about brass or teflon/PTFE glide shoes?
What gearing to you have on your circle rotation (excluding the motor gearbox itself)? It seems slower than my first variant, but more torque, so I'd guess around 1:120?
Your video is impressive - although we do not know the fiction coefficient of the metal/polished wood surface
Sorry for all these questions!
Cheers
Jens