ZProbe
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Z-Probe

This is a retractable ZProbe With a ZProbe your Makerbot is able to auto home not only X Y but also the Z axis This is done by mounting the endstop on your Makerbot in a way it senses the build platform directly and nearby the real ...

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Z-Probe alternatives
3018 CNC XYZ Probe Vice
BusterBeagle3D