Lost connection to cutter

I keep having issues with losing connection to the cutter, it throws up an error message in the middle of a program stating the cutter lost connection . Then when I stop the machine and try to re connect, it fails the first few times and says ”cutter failed to connect and then says “GRBL not found on device”.

Please see this blog post:

If you continue to have difficulties, please write in to support@carbide3d.com and we will do our best to assist.

Likely 99% of the time when you lose connection it is static electricity. As @WillAdams suggested go through and ground your router/spindle, dust collection hose etc. Not sure where you live but it has been warming up but in cold climates and in the dessert static is a problem. You can even get static discharge on the beach at the shore of the ocean when atmospheric conditions allow. I live in Deep East Texas where the humidity is hardly ever below 70%. When a cold front comes through we can drop in the 40% range and I have gotten disconnects caused by static. I know it is frustrating but follow what Will Adams suggested and you will be on the road to recovery.

Some people get the opto isolation for the USB to help prevent static discharges. I would not go that route until you solve your static issues. Whenever you have a moving bit, moving air and dry conditions you can get static. Make sure your outlet is truly grounded a few people have found out that they were not really grounded. I never plug up my laptop when machining unless it is a very long run and my laptop could run out of battery.

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This is what I did to cure my issues.

Grounding your Shapeoko - CNC Machines / Shapeoko - Carbide 3D Community Site


So I have had my Pro XXL for over 15 months and NEVER had this issue until yesterday. Nothing in my setup has changed. Same laptop, cables, dust collection setup…only thing that changed was my CC pro subscription expired.

Maybe it is pure conspiracy theory at play here LOL but I find it odd that no changes in setup and now I am having this issue. 5 times yesterday it happened. Lost ability to download g-code with expiration of Pro…but I created project in Vetric and ran it and no issues.

So I’m pretty sure it’s the grounding everyone is talking about, but I can’t help think also might be computer programming snafu given the circumstances that happened yesterday.

Usually when this problem appears after a period of successful usage it’s worn carbon rushes in the trim router.


AHHHHH I keep forgetting about those pesky brushes. Thanks Will…I give that a try.

Just as of this week, I’m seeing this issue for the first time ever. It’s doing it constantly, about 8-10 times on my latest project. I have a Shapeoko Pro and it’s grounded as required from the manual in setup.

same machine, same problem… solved by grounding my dust collection per post above (dust collection and machine disconnects)

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As noted above:

If that doesn’t get you up and running reliably again, let us know at support@carbide3d.com

I’ll give the dust collection grounding a try first. I’m not using a trim router, I’m using a VFD spindle.

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