[ronateah]

Can anyone give me an idea how i program a fourth axis to run continuously in the back ground as my g code runs

[ger21]

You could configure it as a spindle, but then you'd need to control your regular spindle manually.

[ronateah]

Is that easy to do?

[awerby]

You might try detaching the 4th axis from your system and powering it separately. Sherline sells an autonomous rotary table that doesn't need a computer to run: https://www.sherline.com/product/870...table-indexer/ I don't think it has a "continuous" mode, but you could, for instance, tell it to go to 360,000 if you wanted it to rotate a thousand times.

[ronateah]

Thanks all I think i got it worked out in the G code. Not quite how i was hoping but it will do.

[RCaffin]

Normally I let Mach3 drive the 4th axis with Step/Dir signals, but sometimes I want the 4th axis to behave like a lathe. So ...

I use a single Mach3 output pin to switch between the Step/Dir pins and an external free-running oscillator and a direction switch. The latter does not require any effort from Mach3, and can be invoked from within a program. This works fine.

However, switching back from 'lathe mode' to controlled mode is more difficult if I want to return to the original orientation. I would need to write a macro to keep stepping until the Index pulse was asserted, and to then zero the A axis. (This is possible.) So far I have avoided this need.

Cheers
Roger

[LCB]

Re: G Code to continuous run fourth axis in the back ground