Hypercube 300 Spiral Bushing XY Joiner

One of the design goals for the Hypercube 300 is to keep the mass of the CoreXY mechanism down so it can run faster; this is why it uses things like carbon-fiber rods on the carriage axis. The XY joiners of the original design call for LM8LUU linear bearings, though, which adds significant weight on one axis.

This XY joiner remix fully encloses the bearing so you can substitute the spiral-vase printed linear bushing from here:

https://www.thingiverse.com/thing:2537701

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