When you hit the pause button on the Jog Pendant the machine stops where it is but the VFD spindle does not stop and does not retract. Is that the intended behavior? If so, do I then need to hit the Pause button on the screen to stop and retract the spindle?
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Yes, on an SO5 Pro â the lift on pause feature is in Grbl on other machines but was removed in favour of dual Y-axis homing on the SO5 Pro.
I have a Shapeoko Pro (not a 5). What is dual Y-axis homing?
Itâs a feature on newer C3D machines. On older machines, there is one Y axis homing switch. Once hit, the system assumes the gantry is square to the frame.
On newer machines, there are two Y axis homing switches, one on each side. The system uses both switches to ensure the gantry is square, instead of just assuming it is.
However, the hardware on the controller is so resource constrained that something had to be removed in order to add dual Y axis homing. The feature that was removed was âretract and turn off spindle when pausedâ. Now pause operates just as a feed-hold - only stop moving the gantry.
I personally consider the retract and turn off spindle behaviour to be essential - from both a safety and utility perspective, I absolutely would not get a machine without it.
If the âRestart Programâ feature actually worked, that might help. You could then stop the job instead of pausing it, and just pick up where you left off. Alas, the feature is woefully incomplete, and essentially unusable in its current state.
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The Jog Pendant behind the scenes triggers a âGRBL feedholdâ command that stops movement without parking (lifting) the spindle. It is different than the pause command triggered by the Pause button in Carbide Motion.
This is how basically every single industrial CNC works, and it lets you stop the machine, make sure nothingâs gone wrong, and resume with minimal delay. We understand the ability to park may sometimes be desired, but sometimes people also hate it. Making a solution thatâs palatable to both sides is something thatâs on our radar though. No promises on a timeline though.
@mhotchin I know the Restart feature needs polish, but if you plug in a line number, it usually picks up where it left off. Are there specific cases where itâs not producing the desired result for you?
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Winston, will I get myself in trouble if I trigger the feedhold with the Jog Pendant and then click the Pause button on the CM user interface? In that case how does one restart the job, by clicking the CM start button or clicking the continue button on the Jog Pendant?
The actual restart works great - seems like it does the right thing every time. The problem is with the support needed to make it usable. Unless one is very careful to make note of the line numbers, CM will dump the info and thereâs no way to get it back. In the case of an unexpected disconnect or power blip, thereâs no way to recover.
If CM logged where it was, then one of the options on Restart could be âThis is the last thing I remember doingâ, possible backed up a bit to account for the planning buffer. That would make invoking âStopâ very easy to recover from without having to manually note the line number.
That would probably make it minimally usable. Even better would be added options like âRestart from most recent rapidâ and âRestart current toolpathâ. I would probably invoke the first of these most of the time.
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Showing the gcode line number being executed when a disconnect happens is something coming to a future version of Motion, hopefully the next beta build.
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Winston, I remember Rob also explaining this a while back but couldnât find the post. Thank you for reiterating the concept. Coming from other CNC, it is familiar in concept to me.
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