Hello. I’m new to the forum but have been using my OMTech 70W Co2 laser for a couple years. I’m wondering if anyone else has had an issue with the laser stopping after a few seconds. I was running a batch of stuff and as soon as I changed files, Lightburn said it needed to be updated (to version 2.0.02). I did the update and that was it. Every time I try to engrave, it stops after a few seconds. Nothing else changed except for the update. I’ve reinstalled old versions, rebooted everything, and nothing seems to work. I’ve also loaded my normal use file back to the controller thinking something changed in there and that also didn’t work. I am using the “start” button in Lightburn to run the engraving. I did just find out that if I “send” the file to the controller, it runs fine. Only when I use the “start” button it fails after a few seconds.
Any information or help is greatly appreciated.
Assuming you have a USB cable from the Mac to the laser controller, then this is likely a USB communications problem. The controller starts running the job while the rest of the data is streaming in, which means it’s trying to do two things at once, which is always a challenge.
Macs are notoriously sensitive to USB problems and you may have just rammed into a combination of updates that made it much worse.
Which pretty much rules out LB 2.0 as the cause.
The standard recommendation to use Ethernet, rather than USB, seems to cure many / most of these weird problems.
A recent discussion covers the issue:
Thank you!! If it is that simple I’m going to be so mad! Haha
I don’t have an easy way to do ethernet but I’ll try it. With a new USB cable, do you know if it has to have the ferrite chokes on it? The cable I’m using now has them. Or would an ethernet cable need them? I do have a USB C to ethernet adapter I can use at my computer. If thats the better way to go anyway I can do that. Just not sure about the ferrite choke.
IMO, ferrite cores don’t really add much value to the proposition, but they seem to justify the higher price bringing correspondingly better workmanship and QC in the cable itself.
It also depends on the cable length. If you’re running 100 feet of USB cable, even with a powered amplifier on one end, then a new cable won’t preserve your bacon.
Another thing to consider: if you’ve been plugging and unplugging that poor USB cable on a daily basis, the connectors blew past their Best Used By date a long time ago.
I bought new cables (three to be exact) and tried them all with and without clip on ferrite chokes. none of the cables would even communicate with the controller. It just kept saying no controller found. I used 6 foot and 10 foot cables.
Even though I’ve had this laser for a couple years, this is the controller info:
Total ‘on’ time (HH:MM:SS): 308:12:30
Total job processing time (HH:MM:SS): 103:26:36
Previous job processing time (HH:MM:SS.msec): 0:00:06.435
Total job ‘laser on’ time (HH:MM:SS): 41:41:44
Total job count: 1004
I also tried using all three different ports on my computer.
Suggest you follow @ednisley advice.
Wire it up to your lan and forget about it… that never seems the case with usb.
There is likely a short cable from the controller to the side panel’s USB jack and it’s entirely possible for that jack to wear out. If cabling the PC directly to the controller improves things, you’ve found the problem.
Standard USB connectors have a minimum rated lifetime of 1,500 cycles of insertion and removal
Given that none of the USB cables any of us use are “top quality” parts (because cheap), I’d say at least the USB jumper on your laser is overcooked.
That supports my guesstimate that the slugs don’t actually do anything in this context.
Although I don’t have any hard evidence to support this contention, IMO the “best” USB cables will come from a known brand with built-in / molded-on ferrite slugs, not clip-on split cores, and that’s what drives the price high enough to justify better build quality.
I ended up running a new Ethernet wire directly to the machine and it works perfectly. Was a bit more work than just replacing a cable but I’ve tried a few different files without failure!!
Thank you for all your help!
I am going to try that jumper cable and maybe change the port just because I’m curious now…
Whew! 
Please report back on the USB jumper, because if bypassing it “cures” the problem, that’ll be another nail in the USB coffin.