A specific question about acrylic sheets

materialsources
acrylic
qa

#1

Is there an acrylic that’s black on both sides, but transparent in the core? I have an idea for an edge-lit project, but it’s dependent on either this existing, or painting acrylic sheets in post enough that light ONLY passes on cut edges.


#2

I don’t know of any 3 layer acrylic but it would be easy enough to make either pre or post laser. The water thin solvent glue when properly applied will yield you a solid piece of acrylic.


#3

It’s a thought… Once my GF arrives, I’ll have to experiment. I’ve ONE big project idea that I’m dying to see if I can pull it off. I haven’t seen anyone try this concept yet (I’ve scoured the web just in case) and I’ll be stoked if I can do it first (and IF it looks good, too, I guess.)


#4

There’s this, but I’m not sure that it’s black/clear/black.


#5

I saw that, but it’s just black on one side, clear on the other.
I might just cut a clear acrylic sheet, and then sandwich it with layers on something thin and matte opaque black. Well, we’ll just have to see once my GF arrives! (Got my golden email today, btw!)


Discussion of July Update, Part II (latest)
#6

You need to shout that “golden email” bit - not tuck it in at the very end in parentheses!! :smiley:


#7

And please put an entry in the spreadsheet.


#8

Congrats! :boom::bomb::dizzy::tada:


#9

just spray paint it or glue some together. Id probably go the spray paint method though


#10

Me too. That will prevent any glue induced crazing of the plastic or areas where the glue wasn’t the same thickness or other coverage issues. Way easier to shoot it with spray paint.


#11

The spray paint method would be easiest.

However, paint it before you laser it.

If painted afterwards, the solvent in the paint can cause crazing at the laser cut edge because of the heat stresses induced by the laser.

Or, anneal the acrylic after laser cutting and before painting, that will reduce the risk of crazing.

By the way, I searched google for “light pipe sheets” and there’s some patent info online. Looks like Delphi is looking into something similar for automotive dashboards using laser engraving. http://www.freepatentsonline.com/EP2881279A1.html

They may be seeking the patent but I’ve got dashboard artwork ready to burn as soon as my GF arrives.


#12

Yeah, painting before cutting seems like the way to go, but is that safe for the laser optics? (Quick Robin, to the Bat-Google!)


#13

I use Krylon and Rustoleum all the time without any issue.


#14

Wow…she got this right! Congratulations! They begin to roll again. So happy for you. :grinning:


#15

It may not matter since the exterior will be opaque, but getting a bubble free glue joint across that large of an area is VERY hard to do. I would go with paint as well.


#16

Congratulations!


#17

#18

also, please do not glue panels then cut… the fumes become toxic when you combine cutting with acrylic as per 3M spec sheets. Yes… I have tried it.


#19

Do toxic fumes matter? If you are venting outside or using a filter you should not be breathing the exhaust.


#20

No filter on earth is 100% secure - do not take that risk. The issue is long term exposure.