I hope this is the correct sub-forum for this question.
I have studified a lot of posts and links for DIY CNC machines and there is one issue which doen't seem to get covered. How do you set a reference position rather than a limit switch?
To me a reference or home position is the base for axis position counting and is reached via dedicated buttons or programming G28 XxYyZz. It sets the basis for G54 to G59 or similar work shift systems. How is this done with DIY CNC?
Can a reference mark be added to a stepper motor? Also not all encoders have reference marks either.
With machines that can have indicators in the spindle or can use edge finders this is not a problem. Even lathes usually run G92 or G50 position setting. But some machines like grinders can't 'remove' their 'tool' in a repeatable fashion.
I personally don't think a limit switch would be repeatable enough to act as a home position, certainly as I see their use.
Is this an issue which must be put to one side for cost reasons?
Regards
Davidp
Bristol, UK