I did mention using one double long chain for one rotation axis but I think a lot can be said for just using the same length for both. This reduces part numbers since we can just use the same bits. Standard configuration would come as a 4 part X as shown below but users could also conceivably have 6 or even 8 configurations.
This version is just a couple of aluminium extrusions strengthening two boards of laminated wood, obviously it’s missing some lateral support. If I could also somehow lose the round ‘safety skirt’ or make it optional that would also be nice…
