I am trying to cut through 2mm basswood ply with my 1600 laser. I’ve combed the help, forum and instructions and tried various settings. The latest are a side-by-side of work speed 85mm, 7 passes, 0.4 Z step and 85 / 8 / 0.3. The 85 / 8 / 0.3 did better, but only on the vertical lines – the horizontals didn’t cut through.
The only time I got a complete cut was with something like 15 passes at 60mm and 0.06 Z step. The cut came right out of the ply, but when I put that to my project it would be a 33 hour cut. I want to really cut that down (so to speak).
I’m going to test 60mm speeds with different passes, but I feel like I’m missing something fundamentally simple. I think the 1600 laser should handle the material. Could the material be the problem? Am I missing something obvious?
The SM is calibrated, firmware and Luban both up-to-date.
TIA.
Edit: based on this thread, I wonder if I should roll back my firmware and try again. I don’t see anything in the changelogs that suggests it’s been fixed.
The other things that come to mind other than the firmware are:
Lasering plywood is unpredictable. It seems to depend on what glue was used during assembly: some cut through easily while some are horrible. 15 passes is not out of line for some 2mm plywoods, sorry to say. (I forget whether the record thickness for plywood cut with the 1600W laser was 4mm or 6mm, but it took the person in question ~50 passes, if I remember correctly.) If your design is small enough, you might have better success trying it on solid wood.
Plywood is wood. It’s somewhat flexible and can become distorted from prolonged improper storage (you bought yours from a random Chinese seller on Amazon, so there’s no telling where it’s been). Make sure the piece you have is actually flat.
Luban may be doing something buggy again. You’ll see a lot of people here recommending Lightburn to generate gcode for the laser instead, although it costs $$.
Agree with ElloryJaye, plywood can be difficult. I’m doing both 3mm basswood and 3mm plywood (not sure the wood but probably birch); both are in the 50 passes arena, but I’m also at 200-300 mm/s and 0.08 mm steps. I find much less than 200 mm/s really chars the wood, so the need for more passes. In basswood, I’m getting cut through in probably 10-15 passes in some areas, but in other areas, especially horizontal cuts, it takes all 50 or more passes to cut through. Plywood is even more problematic, but I’m getting through, sometimes with 2 runs on the 50 passes. I occasionally need a razor blade on the backside to get something out. Focusing is important and I don’t like the autofocus. I finally did some testing and settled for about 26mm, which is a little higher than what SM indicates it should be (I think they say 15-23mm?) but better than the autofocus that was up in the 30s! It took me a week of different test cuts to get where I’m at now so you may need to play around with different settings to see what works best. I’m using the 1600 laser also.
In all honesty the 1600mW is USELESS. Maybe ok for cutting thin card stock, but that’s it. I gave up on it in futility, and got the 10W. It should have been the standard from the start. It’s actually capable of doing useful projects.
Thanks for the feedback. I’ll see what faster speeds with more passes gets me and/or try the firmware and Lightburn. They have a free 30 day trial that will let me know if it fixes things or not.
Lighburn did the trick! It kept the print to about 2 hours, and cut 99.9% of the way through in 5 passes at 240 mm/s (good enough for my needs). Luban was giving me 33 hours for the cut, and I think it would have been pretty charred.
Here’s the cut I did for reference. I used 240mm/s, 100% power, with 5 passes for the lines with large spaces between them (perimeters and the rectangles in the stand). My guess is another 1 or 2 passes and they would drop out instead of me punching them out gently. For the smaller stars (they’re about 2-3mm wide) I used 250mm/s, 100% with 4 passes and that was fine. I left the focus height at 10.
For an etched date stamp I used 300mm/s, 50% power, 2 passes. I probably could have gotten away with 1 pass, but I was really, really tired of testing and this needs to go into the mail.