Nomad CNC, no magic smoke but pretty sure the grbl board is toast

We use one of these in my shop at work and in doing some housekeeping i decided to move it and clean the shavings from beneath. That lead to taking the back off and blowing shavings out with compressed air. Now, it doesn’t power on. The only activity is three limit switch LED’s on the PCBA, as well as the blue LED on the power switch briefly stay lit, then dim out. You can hear the steppers engage and also faintly hear a noise from the PCBA as the limit switch LED’s fade out.

I would suspect that i accidently dislodged a metal shaving and it went behind the PCBA. I attempted to remove the circuit boards, but found that after the screws were removed, they were still attached, possibly by some thermal sink epoxy? I didn’t pry too hard before putting the screws back in place.

I saw on here a similar situation with a shapeoko where the LEDs faded out and a new PCBA was in order.

Thoughts? I also made a video and the link is here:
Nomad CNC no start video

Let us know about this at and we will work out how to handle it.

1 Like

You did not say what machine. The original SO3 had a large heat sink behind the controller. Later models removed the large heat sink but there is a piece of thermal tape back there. The way to tell is the cover. If there is a hole on the front side of the cover and it has some thumbscrews to take the cover off it is a newer model. If you have to remove the phillips head screws to remove the controller cover it is likely an older SO3 model. You can buy a controller for around $150.00.

Since you were moving things around just make sure everything is plugged in and nothing got pinched.

I have a lot of woodworking machinery. All of it is on wheels and often I take it to the front roll up door and move outside on the covered patio and give it a good cleaning. I like to blow it off but for the Shapeoko I always vacuum it off and never blow air into it. I have removed the router and blew that out outside to get the carbon dust out of the motor.

He posted what machine it was in his Title, as well as posting it in the “Nomad” section.


It was firstly posted in the general CNC Machines category.

Posterity Update: I contacted support and they recommended me to purchase a new controller board.

New controller board arrived pretty quickly after purchase and was installed. It communicates to the PC and I can run the jog feature and move all axis.
However the machine always stays on with the power button always staying lit.
When you press the power button, it doesn’t do anything. No click, or other reaction happens.
I unplugged all but the power connector from the controller board and it still stays on. I even tried another 24V 6.5A power supply that was a spare for our previous Nomad and the “power always on” behavior was the same.

I contacted support and haven’t heard back yet, being a holiday week, it’s to be expected.

…to be continued.

When you get a answer what it is please drop a update in here. I also have a nomad and I have had to take it apart a few times to clean it and much to carbides attempts, Aluminum chips do get into that control board box even without compressed air. It sounds like a relay is staying on once it is powered up like a latch circuit is stuck powered on.

Will do, hopefully I’ll have a resolution before the topic closes. :pensive:

Support is sending out a new power button as of today.


This topic was automatically closed after 30 days. New replies are no longer allowed.