Here the first prototype. You can see the roughness around the shoulder joint. But I managed to figure out a way to even out the process a bit and make the elbow joints smoother. Still not perfect, as the connectors are both threaded and the joint tightens in one direction and loosens in the other. I’m going to try Drilling out the joint and using a 6-32 5/8″ machine screw instead. There are more permanent solutions but I want it removable for complete customization and repair ability.