I’m new to the laser engraving world and so far enjoying myself. I’m running an Ender 3v2 with marlin 2.2.1 and a 5W output Comgrow laser.
Most works like a charm, but I do get the following strange thing happening: when I engrave at single pas my image is never complete (ie. circles aren’t finished). But when i engrave at 2 passes everything is fine . The downside is that the lines are much darker from 2 passes. Am I making some mistake that is causing this to happen?
Here is an example of some butterflies, right is 1pass, left column 2 passes.
power is always 100% (the downside of using this laser attached to a 3d printer)
i’m working in mm/sec, in which the range is from 5mm/sec tot 200mm/sec , the speed seems to give no different results in which parts are ‘missing’
50mm/s is 3000mm/minute. That’s pretty fast for a laser diode.
I feel that you’re solidly into the cornering or RAMPS algorithm within Marlin and that’s why the intensity is being reduced. I had this symptom last year when I was starting.
If you have the Config file for the Ender 3v2 we can confirm what the maximum print or engrave speed is.
I recommend performing a Material Test on one of the unsatisfactory pieces, 6 by 6 grid between 500mm/minute and 1000mm/minute and 20% power to 70% power. Set the Material setting for ‘Line’. When you are in the ideal operating range the test-boxes will generate a clean engrave line in and out of the corner. When operating above the cornering speed limit, laser power is reduced excessively and the missing line behaviour appears.
This test should be in range to produce a line that does not blank in the corner and provides some gentler line engraving details that you might find pleasant. Ideally there will be an angled progression of light to dark across the grid of samples.
If you are not happy with the reduced speed, turn the test speeds up and repeat the tests to find the upper limit. If the corners of the test grid squares show missing spots, you have proof that it’s related to the cornering algorithm.
