Is there an equivalent to Armour Etch (used in glass etching) for acrylic?
I want to etch some text onto an acrylic sheet but I do not have access to a laser engraver. Sanding seems to be a common approach for achieving the frosted look on acrylic, but I don't see how I can use that approach to etch elaborate text... With a cream like Armour Etch, it is easy to just mask out the pattern and apply the cream...
I scoured the web looking for a simple way to etch acrylic plates and glasses, the way I etch glass plates and glasses using a stencil and etching cream. Could not find anything. Then it hit me - acetone!
Well, I tried applying it the same way I would etching cream and made a big mess.
So what I needed was more control. Instead of straight acetone, I took nail polish remover (with 98% acetone) and a cotton round. I dabbed a little nail polish remover on the cotton, then folded it over on itself to soak up extra. Finally, after applying the stencil, I dabbed the cotton onto the acrylic, rinsed to get any extra off the stencil, and removed the stencil. It came out beautifully, looking exactly like etched glass! (The photo is my test piece, the mess is on the opposite side of the logo shown.)
Sandblasting gives the best effect, but if you don't have the equipment or want to spend money acquiring it, and can't/don't want to just apply the stencil/masking and take it to someone else to sand blast, acetone is the way to go.
I'm skipping the other mechanical methods, as they take a lot more time, patience and skill to give pleasing results (e.g. trying to use a rotary engraving tool for the first time usually leads to cursing and disappointment).
Don't use too much acetone at a time, and don't pour or drip it onto the surface as any drips will also react immediately anywhere it touches the surface.
Work in a well ventilated area, as acetone is very volatile, and breathing the fumes is not a great idea.
To be safe, you can dab acetone on using a cloth, cotton wool or even ear buds for smaller areas.
Make sure your masking/stencil seals properly to the surface and doesn't allow liquid to get underneath the masking and rinse with lots of water immediately after application.
The reaction is much faster than when you etch glass. You can always apply more acetone if the initial effect is not as pronounced as you want.
If your piece is not too large, you can also create the frosted effect by coating your entire piece in parrafin wax (inside too) then removing the wax over the areas you want to frost/etch and exposing the piece to acetone fumes in a closed container over a period of time. This requires some experimentation to find the correct amount of acetone for your container volume and the amount of time to leave your acrylic in the container, as different types of acrylic surfaces will etch differently.
If you are too impatient to vapour etch, you can use a fine atomiser spray.
This method is actually less likely to end in disaster than most types of stencil or masking, as all the remaining surfaces, inside and out, are protected by the wax.
When finished, the wax can be removed using very hot water.
If you make a mistake or the finished surface is too rough, use old fashioned white toothpaste to buff (ideally you would use a 3micron diamond polishing paste, but why break the bank for simple craft projects).
Some acids can be used to etch some plastics, but this is not a good area for experimentation unless you are very sure of your raw materials and the chemical reactions you can expect. Using the wrong combination can leave you with a permanently sticky surface or a melted puddle of plastic.
Lastly, there are several types of "frosting spray" or "sandblast spray" paint available at most building/home DIY stores that are made to mimic the frosted glass look. They are not that wonderful, but it is an option. Just make sure you use the type made for plexiglass, not glass.
Since you are familiar with Armour Etch, I would start there. Apply a drop of Armour Etch to a scrap of your acrylic sheet and see if it reacts. If it does, you have your answer; just mask off the acrylic, cut out your lettering and apply as you would on glass.
If it doesn't work, and you really need it to be etched, you could try other chemicals which act as acrylic solvents. Some modelling glues work on a "plastic welding" technique where the glue dissolves the acrylic plastic so that two previously separate pieces become one. I would also think that pvc plumbing glue which works on the same principle would work (though you might not like it's purple color).
If you just want the etched look then your safest bet would be frost spray paint. It has the advantage that if it doesn't turn out like you want, you can probably wipe it off while it is still wet and try again.
