Loose belts during calibration

[md8n]

@md8n

Current arrangement is (highest to lowest in the stack of arms) TL —> BR → TR —> BL, but this results in the greatest relative height difference between TL → BL

Projecting the various arm heights out can give this visualisation

The alternative that I suggested (BL ->TL —> BR → TR) looks like this when performing the same kind of visualisation