Soft Limits on Nomad 3

i had a question, as I am working with a piece of stock the exact size of my nomad bed, and was curious if the Nomad has soft limits in place to prevent it from over-traveling. I have a program that I think might extend beyond the travel limits.

I did notice that carbide motion seems to not be able to send the x carriage further left than a specified point, which leads me to believe there are some form of soft limit.

are those limited to jogging or do those get parsed when streaming gcode too?

anyone able to confirm? (i guess i could pull the GRBL settings to confirm)

There shouldn’t be a software limit in Grbl — you can check if Soft Limits are enabled by opening up the Log window and sending $$ and seeing what is set for $20

Jogging is limited in Carbide Motion, so that’s the mechanism you are seeing.

It is (or at least was in CM3) possible to slam the X-axis carriage against the side of the machine at full speed (please don’t ask me how that happened) using G-code — my suggestion would be to make up a file which move diagonally from the corner to other corner along this axis plus desired distance, then run that file and be prepared at the power button when it runs into the physical limit — measure how far it moved and you can work out what the actual travel allowance is.

okay. good to know. will setting soft limits in the machine settings / grbl screw up carbide motion while streaming gcode at all?

We advise leaving soft limits off — it results in really, really hard to diagnose problems at our end — in theory it EDIT: might be okay, but no one is testing that configuration, and the first thing we’ll ask from support is that you disable it.

FURTHER EDIT: So as Rob notes below, please don’t enable soft limits.

no worries, just figured i would ask.

will carbide motion parse the gcode moves while streaming to prevent overtravel or is that still not implemented? (i realize i just asked this, but is it possible to confirm with the software dev dept to confirm if CM7 will check before crashing?)

I don’t think CM will check for movement outside of machine working area — the test I just suggested would verify that.

cool, thank you :slight_smile: ill see about doing that test. just a little nerve-wracking to potentially send it towards a crash on purpose lol.

Yes it will. Do not setup soft limits on GRBL.

Right now, CM will limit the jogging to slightly less than the cutting area of the machine, but it will not limit anything during cutting.

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okay cool thank you!

When you send the config that sets jog limits. You can slightly increase config parameters. Just dont set so big the machine hits the mechanical limits.

As @WillAdams and @robgrz said the gcode could send the x and y a half mile but you would hit the mechanical limits and grind. Gcode will not limit the size but the mechanics limit you.

i understand that the gcode doesnt limit anything by itself.

I was mainly if Carbide Motion will check the gcode move against the physical limits and prevent an out of bounds crash, which Will answered.

At this time it will not, but it’s an area we may look to improve on in the future.


that would definitely be nice feature.

I crashed my old CNC a few times not thinking about the fact that the machine knows nothing about travel, and my 3d printer once (real big part), so im a little more aware of it, when doing parts that are close to the bed size of my machine.

plus this one was way more of a financial investment, so im much more cautious about doing something im not 95% certain will work.

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