Pausing loses steps - any solutions?

Hi - I have a Longmill Mk2 48x48, and I have a Digital Loggers IOT relay that triggers the router on and off. If I pause a job and restart the job, the router and the CNC x/y/z translation start at exactly the same time. Because the router isn’t up to speed yet, this causes the CNC to lose steps. I’m finding that these open-loop steppers are almost more trouble then they are worth for complex operations! At any rate -

Does anyone have a solution for resuming operations that spins up the router for, say, 1 second, before resuming the translation steps?

(not ever pausing a job is certainly one option for solving this problem, but it’s impractical with complex setups and many accessories, like dust shoes that might need adjustment and so on)

@cvandermey I’ve moved your topic to the machine help category to give it more exposure.

Just to add some clarification, when you pause the job, you are turning the router off somehow, yes? I don’t use a relay, so excuse my ignorance. Does the pause command send a signal to the relay to turn off the router? I’m assuming that it does.

I’m in the process of upgrading to a spindle where you need to insert a dwell command to let the spindle get up to speed before plunging into the work, sounds similar. IDC woodcraft posted a YouTube recently on how to accomplish this.

Grbl has this built-in if you enable “safety door” on feedhold.

@jpnharris @NeilFerreri But, the OP is using a router on a relay, not a spindle that is code controlled.

Something is triggering the iot relay. He can’t control the speed of the router, but the on/off should be controlled by M3 and M5 commands.

@NeilFerreri Tks, Neil. I’m learning. :grinning: From @cvandermey description, the relay and codes are working on initial startup. It’s when he pauses the job in gSender and resumes that things go bad. He has not yet replied, but I have to assume that, during the pause, he shuts off the router. He does not say how he is doing that - some code or the on/off switch. I’m assuming - again - that he does it with code sent to the relay since if he turned off the switch, he would simply turn it back on before resuming the job.

Anyway, at least for my education, I hope that he comes back to clarify.


@cvandermey Did you resolve our issue, Chris?