i’m relatively new to laser engraving with lightburn but i’ve used cncs for many years. i may be missing something but i’ve been reading forum posts here and elsewhere and can’t figure out what the issue is.
my setup is an atomstack a5 pro connected by usb to a macbook pro running lightburn.
i’m trying to burn a single-layer vector file imported from pdf, created in illustrator. i’m attempting to burn at a single depth on solid wood (in this case walnut but i’ve tried on a few different sample pieces with the same result).
that’s one single object with no overlapping components. it’s about 300mm tall for scale.
the problem is that, while most of it burns perfectly, in the stalk where it is thickest, there is a significant part in the middle where it burns twice as deep.
i have tried playing around with the settings but i really don’t know what is happening. i’ve used the same settings for other burns, mostly decorative text, without any issue.
the settings i burned with most recently on it that had this issue…
connecting using grbl
speed 100mm/s
power 85%
overscanning 2.5%
line interval 0.0220mm
fill shapes individually
i’d be happy to share the original pdf if that would help and i can answer any other questions. i’ve just tried to write whatever might be relevant but i’m sure there are other things useful to know.
it’s a stock a5 pro machine with no modifications.
i didn’t edit it in lightburn, just imported it and burned. no need to trace because it’s already a vector file from the pdf. i’ll attach it here.
i’m getting good depth on the rest of the burn, just the thickest area of the stalk seems to be burning much deeper than the rest. if i turn the power down, will that mean the rest doesn’t burn as deeply?
i’m so used to doing this with a cnc where the depth is a fixed variable that i’m a little confused how i end up with multiple depths from a single setting.
sorry for that: i don’t know, you have to test it; i have a different laser (20W Diode) an i’m engraving with 40 % power. To adjust the desired depth i adjust the speed, mostly 4000 mm/min.
But that differs from laser to laser and from material to material.
I opened your file and it came in at 100mm/min@85%. That is extremely slow for engraving. You don’t state what output power your laser has, but on my 10 watt fill engraving is usually done in the 3,000 - 6,000 mm/min range. Also your line interval is very low / high LPI. You’re running over each spot 3 or 4 times at that setting. Try changing your line interval to .08 or .10.
That Line Interval seems extremely small for a diode laser, because the focused spot size will be on the order of 0.1 mm, possibly 0.2 mm on the beam’s longer axis.
The beam will be hitting the same place four or five times, which will definitely increase the burn in places where the beam is active for a long time.
Try it with an interval around 0.1 mm or, better yet, run an Interval Test over a range of line spacing from 0.05 to 0.2 mm.
You may get a more uniform “exposure” with Fill all shapes at once so the beam travels across the entire pattern at a constant speed.
Google says the A5 Pro is a 5.5w output laser. @ednisley is right, 318 LPI is about as good as you can get (no matter what the advertisement says). You will also find your jobs will complete about 3 times faster or more too.
Sorry, i didn’t change the power and speed values in the helpfile.lbrn2;
it was only to check, if the imported image is a vector grafic or not.
For me it is self-evident that for all files uploaded here in the forum the values for speed, power and line intervall etc. have to be adjusted, both to the respective laser and to the material used.
As i wrote above i’m engraving at 4.000 mm/min with my diode 20W laser.
This is only true for shared files. If an upload is requested for diagnostic purposes, like we are trying to solve a problem, then the settings actually used should be included.
@Tilman , the intent here is to see if the settings are reasonable, not to always run the file. We look at the laser and layer settings to see if they are in a reasonable range for that machine. Sometimes we ask for a snapshot of the device and machine settings, because those settings are local device dependent.
Yes, you are absolutely correct the settings might be useless if you would be renning my file.
