I have this machine using GRBL 1.1 with Lightburn. Today I was trying to perform the material test for diode laser cut-out. and I left the setting as a 10 x 10 array of 5mm squares, Power array of 10% to 100 %, and Motion array of 30mm/p,m to 1200mm/p,m. Also I am using air assist at 2.5 psi. It never cut all the way through the.
Wheras I also performed the sam test on 4mm “white” plywood, and it cut half of the squares out and I stopped the test on the last row cause it was about to start a fire…
What gives?
Do I need to set the Acrylic on a mesh, like expanded aluminum? OR
Is anyone having luck cutting acrylic(acrilite). I was hoping to be able to cut 1/4" clear with this laser… Maybe my expectations were too high, and I’ll have to cut that with the router instead…
Isn’t that a diode laser?
Yeah, It’s a “30 Watt” laser module on a CNC router base. The acrylic was purple, not clear. and the test was a one pass type. After the test I also created a 30 x 30mm square and ran it at 85%, 30mm/min @ 6 passes, and it still didn’t cut through..
I am assuming that acrylic is not in my lazering future, and I wanted to make some “boxes.py” notes holders for my wife..
Simple fact is acrylic is clear, when it’s colored you’re heating the coloring, which damages the material.
Some colors, like your beams color may reflect off it totally or enough so it appears there’s no damage.
Might have better luck with black, but no matter what, it’ll be by indirect lasing.
Have fun 
If you have plans to cut a lot of acrylic in the future, investment in a CO2 laser may be worth it. As mentioned, diode lasers are not up to the task due to the wavelength they use.
Thank you guys..
Now that I know, I will have to adjust my approach toward acrylic materials. I have a friend that will give me 2’ x 5’ pieces of 1/4" thick “ACRILITE” clear, and I had dreams of goodies to make with the laser from this free material. I guess I’ll get good at milling it with the router. But for this instance I was trying to make a “Post-it note box” with 3mm purple material, and it just wouldn’t cut through.. One question is: Wouldn’t I need to put a “dark mask” on clear material cause the beam would just “shine” through as is it were ‘glass’ without it? These sheets have a white paper on both sides and I have been leaving it on the sheet until I have my projects close to completed, but it ‘fray’s’ when using with the router. I still leave it on and I file and sand the exposed edges. That removes the ‘fraying’. ACRILITE is not easy to work with in thicker dimensions cause it is used primarily for store front windows. I have been cutting the rough material with a jigsaw using a very fine tooth blade, and coating the waste board side with blue tape, then crazy gluing it down.. So far none of my part have come loose while milling..
White is likely to the worst color for a visible light laser. To get white it needs to reflect all colors.
Yes, that’s what indirect lasing really is… However, it’s only good for the surface, as soon as you get through the dark mask, you’re back to clear acrylic. That puts you back to you can’t cut clear acrylic with a visible light laser.
Note it says co2.
Yeah… By the way, That site is the most complete information about working with Acrylic products.. I have had it in my web prefs for a long time, and have read through it a time or three..
I knew I couldn’t laser cut 1/4” with this 30 Watt module, but colored 3mm seamed plausible. Also, I’m ok with machining the 1/4” clear, but according to the website I might need to eventually get another set of drill bits and grind/sharpen them to their specs. Although I have sharpened a lot of larger drill bits, the smaller ones will need a Dremel jig, like a drill doctor but at the right angle and pitch.
You can probably manage black acrylic, it really depends on what color or frequency your laser module produces. A blue light just gets reflected off a blue piece of acrylic.
Have fun
I had acceptable results engraving a logo on black acrylic with a 5W blue light diode module. But it was heating the pigment and melting the material, not properly cutting/vaporising it. Surface damage only, the indirect effect described above.
I could not cut the plate, and it was only ~2mm thick. But the lines from the failed cutting attempt were useful when I used my tablesaw to finish the job. 