This Z axis has hit the same micron (±0.8μm) more than 200 times in a row over most of an hour of Z probes in a "Minamil" rig (this project). Practical repeatability appears to be within 25μm (0.001") after warm-up. In other words, it can resolve micron-scale dimensional creep as stepper heat spreads through a structure.
So how did that take half a year?
- June: #MRRFX and whY rethink Z
- July: Z v3: counterweight delete (& other wins)
- August: Z v3 -- counterweight delete -- progress
- September: ... still sorting Z axis repeatability ... (& Byproduct of debugging Z repeatability)
- October: Z v3 survives slow learning -- and a bonfire of time
- NovemberDecemberJanuary: writing the how-to very slowly
Someone at Instructables apparently liked the 'ible enough to send it straight to the home page: