You mean that the Pi is able to keep running cncjs and cutting continues, even after you lose contact?
That would rule out power failure as a possibility, leaving some kind of network issue.
So you have three devices here, I’d try to isolate the problem to one of them. Fortunately, this should be an easy check.
When the connection drops out, try connecting to cncjs with another device on Wifi, like your phone. There are a few possibilities:
- Your phone connects to cncjs and wifi: this would indicate that your laptop is having issues.
- Your phone fails to connect to wifi: this would indicate that the router is failing for some reason.
- Your phone fails connects to wifi but fails to connect to cncjs: this might indicate that the Raspberry Pi’s network connection is dropping out.
Once you know where the failure is, diagnosing it should be much more straightforward.