Chemically etching acrylic?

[Sound Mind]

So, I plan to mod a case in the future with an acrylic window with an etched design, which of course when lighted properly would look quite cool.

Anyhow, I want to do two things to the acrylic window I plan to install. A, I want to paint it black with a smooth, glossy finish, but B, I also want there to be an etched, not painted design in the center. Since it's going to be painted, abrasive etching sounds out of the question as I'd probably grind off paint around the edges of the design and it'd look awful, and if I grind it, then paint it, I don't know how the paint would react around the edges.

So chemical etching sounds ideal, as I can etch the acrylic with more precision. So does anybody have any experience with chemical etching? Or knows where to find a good DIY guide?


Or, alternatively, is there a way to etch the entire surface of the acrylic, and still paint it so that it's a smooth, glossy finish? Because that would just be easier to etch the entire thing, and tape over the area not to be painted.


Thanks in advance for all your advice!

[Force Flow]

bit-tech might have some guides.

[>:() - Tiki Man]

An easy way to get the effect your are looking for would be sanding the whole panel with high grit wet/dry sand paper, so that the whole thing looks clouded; not to mention, that would make the paint adhere to the acrylic better.

[Sound Mind]

Well, the effect I'm trying to get is similar to this:
http://www.kaylyns.net/images/photos/southern%20pacific%20aluminated%20sign.jpg

The illuminated part would just be a Batman logo. I was thinking of putting some glow wire inside the molding so it would make it... well, glow. Duh. Without lighting up the rest of the case. The Batman logo would be etched, then everything but that would be painted.

So... would the easiest way to get that effect be to just sand the whole surface, and paint everything but the logo? And... what, two coats of spray paint? Three?

One idea I had was to make the first coat aluminum or chrome paint. Then a couple coats of black. Both sides identical, obviously. That way (I think) the light wouldn't escape the acrylic before illuminating the logo. Would that be worth the trouble?

[>:() - Tiki Man]

Actually, you know what would look really cool that you might not have considered would be to get some window tint film, put it on, then with a really sharp utility knife cut out the logo that you wanted;

an other option, you could mask off the area around the logo with plenty of masking tape, then using fine grit sand paper make just that area clouded.

fyi, acrylic is very easily affected by solvents, so if you do decide to do painting, make sure you use the right paint

[Ahura]

Hydrochloric acid

[David M]

To me that looks like it could have been sandblasted or beadblasted. Find someone with one and take in a sheet of acrylic to experiment on.

[bailey]

Hydrochloric acid

I think that is supplied in a plastic bottle.

also isn't that just plain spit ?:confused:

[Strider]

I work for an automotive paint manufacturer and this sounds like Translucent White Paint (It actually looks like a very light blue) under a black coating (although you obviously wouldn't be using the black) . In my opinion the best way to do that is to Mask off the non-painted area and then just pull the masking off when done painting, the Translucent White should have enough light transmission value to give you that look. The only problem is I don't know where you would get that type of paint, although I think you could find it by doing a internet search (Google is your friend:D ). Next time you get in your car at night look at your lighted controls and you'll see what I'm talking about.

[Sound Mind]

@David M - I did was thinking sandblasting/sanding at first, but I immediately started worry about either accidentally grinding the tape away and ruining a fine edge, or when painting it, the paint would pool in a groove and also ruin the edge. So I figured I'd ask for simpler ways first, to see if there were any.

@Bailey - Saliva is partly hydrochloric acid, though it's very, very diluted. Otherwise you'd digest your own mouth. Highest concentrations are found in the stomach. And even there, it's fairly diluted. Also, it would suck spitting on an acrylic sheet for hours. :-P

@Strider - That's an interesting idea... If I can find some for a good enough value, I might give it a shot. I figure I may as well paint the whole acrylic piece first, then mask off the center and paint the rest black. If that'll look good, that definitely sounds like the simplest way.

[tigstah]

i remember when he screensavers was on, yoshii did a segment on laser etching. thats another option.

[not important]

Sound Mind
A lot of automotive shops have Bead blasting cabinets. Glass beads (the most commonly used medium) will leave a very nice etched effect on Acrylics (Lexan in particular). Regulating the Air pressure to about 15-20 PSI will not tear the masking tape.

[Stuey]

I'd also argue in favor of sand/bead blasting, although that might be costly to get into if you cannot or choose not to have a shop do it.