Picture of Improving Laser Etched Acrylic Panels with Acrylic Paint
Laser etching is a great process but I've often wished I could have higher contrast etched text, colors, etc. Then I realized I could do that very easily. If you're laser etching acrylic sheet it already comes with a protective paper covering which makes an awesome paint mask.

So the basic process is deeply laser etch the panel with the protective paper in place. Paint though this protective paper mask. You can be as sloppy as you like. Then simply peal the paper away. Now you have super clean highly detailed etchings, and the paint is protected because it's actually recessed into the plastic. (That's why you use a deep etch.) You can use any color or combination of colors you like.

Step 1: Deeply etch the design with a surface mask in place.

Picture of Deeply etch the design with a surface mask in place.
Do a deep laser etch of your design on acrylic with the protective paper in place. I suppose you could also try this by pre-masking non acrylic object. Like putting contact paper on wood, etc. But I haven't tried it and I'm not certain we're allowed to vaporize contact paper in the laser I have access to.
MarkWarwick5 years ago
 Aw man my acrylic panel already has the paper peeled off of it! Otherwise this would be perfect
look up a product called Laser Protect Mask 5900. I use that all the time for exactly this type of process. Also to keep smoke discoloration off of wood for a sharper edge to the etching. If that is out of your price range, you can always just use plain old masking tape, or paper transfer tape for vinyl, though these may leave a residue on the etched area of the acrylic.
kurt.schaefer (author)  MarkWarwick5 years ago
It's not to late, there is still a trick I sometimes use where you use a piece of rubber to  sort of squeegee the paint into the etched recesses, and off of the surface.  I use one of those pink "SpeedBall" rubber chunks sold for doing print making.  You could get away using other rubbery things like one of those white art erasers, etc.

It doesn't work that great if you have lots of different colors right next to one another, but other then that it can work even without the paper.
 ohh that sounds ideal! I would just want one color, it's a control panel. Does the paint clean off easily from the un-etched surface while it's dry? I have a dud I can try it on first
kurt.schaefer (author)  MarkWarwick5 years ago
Yup, well it depends on what paint you're using. I just use acrylic paint and try to clean off the surface before it's 100% dry.   When it's not 100% dry you can just buff little marks away with a paper towel, etc.

Definitely try on a dud first.  :]

Thanks for your advice. In the end, the paint didn't stick too well, but it is still legible in person. The panel was for a function generator based on a kit that Collin Cunningham designed, and he liked the final results!
Travpena3 years ago
I dont suppose you know the brand, thickness and type of plastic you're cutting out? i just starting to learn to laser cut and having some trouble what can and cant be cut.
kurt.schaefer (author)  Travpena3 years ago
Well those particular examples were cut/etched in 1/8" Acrylic. You can cut any sort of Acrylic on a laser. Max thickness depends on how powerful your laser is, edge quality you desire, etc. I've never worked thicker than 1/4". (In part because of material cost)
gmjhowe6 years ago
That is a great technique! i wish i had access to a laser cutter..
This is a great technique. We did this when making signage for our building.
I'd like to see that sign...
Awesome instructable...it's so simple to just paint over the paper!
jeff-o6 years ago
You mentioned earlier that metallic paint doesn't work so well with a brush - perhaps it would be better airbrushed.
kurt.schaefer (author)  jeff-o6 years ago
Good point. I bet that would work much better. I haven't had a chance to try it though. (I think I have all the parts for a very basic airbrush around, but we moved recently and so much of my life is in boxes that I haven't had a chance to track down the bits and give it a try.)