If that’s the smallest dot, then that’s the best focus.
If some other people are having success and you aren’t, you might have to try and find a different plywood with a different glue used.
The cheap 3mm birch ply I have at my house took 50 passes to go through and charred extremely badly.
I can’t recall other people cutting through 5mm plywood with the laser here, that is surprising to me. I have seen 5mm solid wood be cut though.
On reddit, those other people are also snapmaker users? Is it possible they have a glowforge or some other CO2 laser? Those work well for that as the laser uses a different wavelength that interacts more strongly with the glue used. Also a stronger diode laser would work better, if they had like an 8W laser instead of the 1.6W on the snapmaker.
Thank you for the feedback, That kinda sucks cause I just bought that 3mm 4’x8’ sheet for $40 and spent time cutting it into 12"x12" sheets. Yeah, one guy had a SM A350 that took 20 passes to cut the 5mm plywood. At that point, the CNC bit would be faster. Is it possible to upgrade the laser on the SM2?
That doesn’t seem too bad. Definitely at the longer end but well within normal range.
Just to be clear, since there is some confusion on this, the measurement is from the work piece to the laser lens. Not the distance to the lens hood (which is adjustable and removable). The distance to that is around 5mm. Smallest dot is what you’re looking for.
As @brent113 said 3mm seems to be the usable limit for plywood, but that’s totally dependent on the type of wood and more importantly the glue. Just have to test and see.
If someone actually did 5mm I’d be surprised, but it could be possible. If you can increase airflow around the cutting spot it can help.
So, it must be the glue, I used work speed of 75mm/min 2 passes and pass depth of zero according to the snapmaker chart and was able to cut 1.5 mm cleanly. Looking at the provided plywood it’s 3 ply. Any good sources for this material?
Any plywood with an organic binder would do better than the inorganic resins typically used. I haven’t found a good source though, I just use solid wood instead, usually pine. I’ll save the plywood for signs or images with things etched onto it, and not cut clean through.
I’ve had good luck with stuff I picked up from Hobby Lobby but no clue as to what it was other than being birch. I can check when I get home if there’s a label left on any of it I still have.
When cutting with multiple passes you should change pass depth to keep the beam at optimal focus. Generally that’s approximately the thickness of the object divided by # of passes.
Hello Edwin,
I am working on my Laser, when I first started about a week ago, everything seemed ok with the calibration print. All lines on the “Ruler” looked good, and the camera picked the best. Now when I try to do the exact same thing as I did, the Laser head starts almost on the surface of the wood and moves up as it should for each line. It only prints 8 lines, and they are very week, and the inspection fails every time. I have manually set the Laser Height, it is currently at 17.5mm. Any ideas?
I have been doing some testing, if I set the Laser Height to “0”, I get 2 more lines of the “Ruler” to print, making it a total of 11. The machine still fails the calibration though.
It is very strange. If I’m right, taking off the cylinder should not change the focus. Probably now you are starting the test at a different Z, but still… In my experience, you don’t get just a few very defined streaks like in the photo you attached, but you often see how, as you lose focus, the streaks become dimmer and the contrary when you are moving into focus.
No more ideas. Sorry.
