I recently got my second laser up and running and figure it’s only a matter of time before I need to run them both at the same time. Before I try and fail, causing scrap and lost time, figured I ask if there are any issues doing this.
Not sure what a worst-case job looks like, but there’s a very real likelihood I would be running two greyscale image jobs that would take around 4 hours. One around 254dpi and the other at around 600dpi, so a fair bit of data moving around.
Both GRBL lasers, connected via USB to Win11 PC. i7, 32GB RAM, Nvidia graphics, etc. It’s not a Monster, but it’s also no slouch.
I have a local NAS I can/do use for file sharing and I’m not opposed to getting a second PC but I’d rather conserve the already precious workshop space.
With a single PC driving two lasers, I’m imagining running two instances of LB and setting up a second monitor. One monitor for each instance.
You can do that, but it’s not required. I operate three lasers with a single ThinkPad (10+ years old) using one screen. Works fine. You open another instance and that’s it. You need to switch view to see the other instances, but I usually don’t need that at all.
I don’t do very long projects usually, but I think I had them at least running for one hour in parallel.
I save my project files to OneDrive and have all my LightBurn PCs synchronized that way. It seems it’s not recommended to use shared drives because LightBurn has issues with this, but I never had a problem yet.
Another note: grbl laser are running at 115200 baud usually, so, no matter what data you send (image or vector) it will never transfer more data than 11kB/s. You can run many jobs in parallel until you reach any bus transfer limit
I discovered today that you cannot run one laser off 2 instances of Lightburn. Before you click on the reply button, I did not try to run both at the same time. In the second instance, I wanted to check some GRBL parameters, but it would not talk to the laser. So I will limit myself to copy/pasting between instances.
I accidentally discovered that if you try to change a device’s name while it’s running a job, it WILL let you. It just instantly disconnects/reconnects/homes/etc. and leaves the laser firing while bulldozing over your workpiece clamps and stalling/grinding.
Oops. Bonehead move, I suppose, but now I know.
It was a rather impressive display of ignorance, at least. Too bad I was alone. Nobody got to see my “oh, fudge!” face.
No, that’s not possible. A COM port or better serial connection can only be used once at a time. If you have one LB instance talking to a laser, you can’t access that connection from another LB instance. It would lead to a total mess, because both would be talking at the same time. That’s already handled by Windows, if one tool uses the COM port, the others get blocked. LB will tell you “COM port busy”.
