Two layer acrylic

Great project! I have a pile of two layer acrylic I’m waiting to use… hopefully soon🤞

4 Likes

This would be cool to make the Periodic table on for a small version to keep on your desk.

8 Likes

I am assuming spacing them and doing multiple passes pausing in between might/will help. If I were doing it at home with the a glow forge it would be easier to do that than being in a lab at work where I just want to get home at the end of the day. I will post a ton when I have a unit at home - I have plenty of ideas for projects.

3 Likes

I’m thinking engraved from the rear on edge lit on a piece of florescent green acrylic. :thinking:
Maybe even inlay the green into another color.

1 Like

The yellow on black material looks very clean when cut. Others have been reporting that dark-on-light color versions of this material tends to leave a dark residue on the lighter lower layer when engraved.

1 Like

I used the two color ABS in my picture. It left the residue. The two color acrylic may act differently.

2 Likes

This was exactly what I was wondering about. Would masking even help in cases like this?

Or a second low power pass on the engrave to burn off the residue?

2 Likes

Well, I have one each of every inventable 2 color sheet coming in 3 days to play with. (and 5 each for the colors I already know I want to make work). figured it saves time to just order everything in their store once and test. I’ll do the same for proofgrade and have photos and settings in my evernote if I need to remember which I liked and didn’t.

I’ll let you know how light on dark is vs dark on light. I have access to an epilog and a universal laser - I’ll be honest the universal with its narrower beam basically melted through to the back of the 2nd ply and came out crappy - and I pretty much think the universal’s print settings dialog hates me so I went to the epilog which I’m much more familiar with - and was able to get this type of result with just four individual tiny test pieces. woot. And yes the yellow on black came out with deep good looking blacks. Love it.

I think I’m liking the just get one of everything and try it approach at this point. I also just bought off ebay misc busted metal iphones and macbooks and will use them to perfect etching on that stuff. Some guy sold a bulk box so I have dozens of the backs of iphones (all with cosmetic flaws which were replaced because of the cosmetic flaws) but perfect for learning/experimenting.

11 Likes

OK - so what I did was change the cut order - I did vector cuts in one direction first, then the other direction - this made a ton of little rectangles, then I did the rastering across all of them. No more warping pushing it into the laser. Can crank out about 40 every 9 minutes on the epilog at work this way and no need to babysit it and zero discards.

2 Likes

Interesting. The opposite of the usual advice. But if it works.

1 Like

The next time I do some raster blasting (great term!) on acrylic I think I’m going do it with the air assist turned off.

I want to try it that way because of the results shown in this video…

6 Likes

@dave1 did you figure out good engrave settings for 2 color acrylic? I’m trying it for the first time and the colored dust (red) is settling on the engraved white areas and won’t come off.

Tried the default PG engrave setting first but that looked awful. Then the soon-to-expire PG light light engrave and that is better but nothing usable. Tried 30% & 1000 but that doesn’t even bow through the plastic masking. Gonna raise power a hair & slow it down a little and see if that works.

@Mike13 I found that changing from PG engrave to Manual, changing power to 1/2 of the default PG setting and increasing the number of passes to 2 made a huge difference.

2 Likes

I don’t fire through that plastic masking - I remove it and go with either no masking or shoot through blue masking tape if I’m feeling really picky that day. I have not gone after the settings for the glowforge yet - only the universal at work.

Yup - that totally did the trick. Wasn’t sure if you were basing it off of the light or dark setting, so I split the difference between the two. Probably could have just halved the light and would have been good. Thanks for the suggestion @jbpa!

3 Likes

Either way, what I found was that the first pass engraves through the top layer, but leaves some colored residue behind. The second pass cleans it up since it doesn’t have to engrave through the colored layer and the residue is so fine.

4 Likes

Finally got a chance to check this out on the glowforge.

For me:

  1. I peel the masking material off before running it through
  2. make sure you have the ultra thin second color stuff on the side with the laser.
  3. engrave: i am using manual cut, thickness 0.05", 1000 speed, 20 power
  4. cut is manual of thickness 0.05", 350 speed, full power

this got decent results for me.

notes:
a) if i move slower than 350 for cuts then the material gets melty, stinky, and leaves a sticky residue on the bottom side of the print.
b) If doing patterns I ran a second pass on engraves. and I tended to pick “patterns” vs “dots” because I liked the effect for the couple things I played with. If just doing black and white with no patterns/halftoning that will be done by the software then I just needed one pass and was perfectly happy.

10 Likes

Worked perfectly!

Thanks!

2 Likes