Double Check Your Laser Settings
TLDR; If you added your laser to Lightburn manually, check you added it as the correct controller. GRBL M3 1.1e != GRBL 1.1f.
I recently purchased a Creality Falcon 10W as my first laser, because it was on sale for a decent price.
As soon as it arrived I loaded up the SD card and ran through the basic eagle test cut. It was flawless. Aside from a few light scorch marks, it cut through every tiny detail in the wings and was generally an amazing experience.
I then set up my laptop and cable into it, getting a Lightburn trial to see if I could do some custom work. Lightburn wouldn't pick up the laser, so I added it manually as a GRBL-M3 (1.1e or earlier) on the advice of AI because I couldn't find a manual or forum posts detailing the correct settings.
I had heaps of leftover 3mm MDF, I thought it would blast through this no problem, apparently not. The laser would barely punch through at 2mm/s at 100% power. So I go back to the basswood supplied with the laser and the same eagle template, same issue.
It would either not go through at all or barely punch through at a slow speed. I read that MDF is tricky to laser through because it's so dense with glue and fibers so I thought it was just a case of needing to get the right wood.
Long story short, I was wondering why some settings weren't available even though they definitely should be available on my Falcon so I did some research and I should have added the laser as GRBL (1.1f or higher).
Now it absolutely blitzes through any of my stock, MDF, basswood, ply, etc. Faster and less scorch marks to boot.
Now it's obvious as to why the SD card laser cut was perfect, but everything since adding it to Lightburn was terrible, the Falcon knew it's own controller and Lightburn was forced to use the wrong one.
Sorry for the block of text, I just wanted to tell the story just in case someone else is having the same issues as me and is on the verge of giving up like I was, thinking cheap laser cutters just aren't worth it. They most certainly are and I'm having good fun with it again.
One question though: Why couldn't Lightburn find my Falcon in the first place that I had to add it manually? Driver issue?