Etched enclosures -- adding background colors post-etch?

[EBK]

I love the look of etched enclosures.  I have most of the supplies on hand ready for when I decide to tackle my first etch, although ironically, I'm missing a household iron. 

My question is: Is there any reasonable way to end up with something other than bare metal for the unetched background of a finished design?

[deadlyshart]

ironically

WHY MUST YOU DO THIS TO ME

Anyway, I think there are a couple ways this could maybe be done, though I haven't tried any myself.

One way: Do a fairly deep etch. Do the first paint color really thick (several coats), and the second color very thin, one coat. You start sanding, and because the first layer is really thick, you should be able to stop when the top layer has been sanded off, but the second layer is still there (on the embossed areas that would normally get sanded down to the metal). The recessed areas will still have the top paint layer.

Another way (maybe?), though it would only allow you to get black as the 2nd color, would be to do the normal process, but after the bare metal is produced, do a very brief ferric chloride etch, which normally turns the Al black. It seems like organics are pretty resistant to the acid, so the spray paint (other color) would probably be unhurt by it. This would let you get black + other color.

Another possible way, though this is very speculative. You do the normal process, spray paint 1st color, sand off paint from embossed areas. You apply another easily dissolved layer (nail polish?) over the whole thing, let dry. You then sand off embossed areas again, then spray paint second color. The second color will end up directly on the metal of the embossed areas, and on top of the temporary layer for the recessed areas. You let it dry, then dissolve that temporary layer in a solvent. This method might be tricky/impossible because it might be hard to find something that could be dissolved, but wouldn't also dissolve the first spraypaint layer. Just a thought, though.

[karbomusic]

I've had some light success just coloring it in with an ink marker (Sharpie) then using a sanding block to remove any places I "went outside the lines".

[deadastronaut]

Paint the etch,   

then paint latex into the etch.

paint whole box...

peel off latex...

Clearcoat...    just a thinking aloud...

[EBK]

ironically

WHY MUST YOU DO THIS TO ME

No idea. 

Anyway, I think there are a couple ways this could maybe be done, though I haven't tried any myself.

One way: Do a fairly deep etch. Do the first paint color really thick (several coats), and the second color very thin, one coat. You start sanding, and because the first layer is really thick, you should be able to stop when the top layer has been sanded off, but the second layer is still there (on the embossed areas that would normally get sanded down to the metal). The recessed areas will still have the top paint layer.

If you think carefully about this, the end result would be indistinguishable from a decal.  NM, I think I misunderstood which layer was first/second/top.Still, not too sure I want a thick coat in the engraved areas.

Another way (maybe?), though it would only allow you to get black as the 2nd color, would be to do the normal process, but after the bare metal is produced, do a very brief ferric chloride etch, which normally turns the Al black. It seems like organics are pretty resistant to the acid, so the spray paint (other color) would probably be unhurt by it. This would let you get black + other color.

Interesting.  I wouldn't mind finding out what that would look like.

Another possible way, though this is very speculative. You do the normal process, spray paint 1st color, sand off paint from embossed areas. You apply another easily dissolved layer (nail polish?) over the whole thing, let dry. You then sand off embossed areas again, then spray paint second color. The second color will end up directly on the metal of the embossed areas, and on top of the temporary layer for the recessed areas. You let it dry, then dissolve that temporary layer in a solvent. This method might be tricky/impossible because it might be hard to find something that could be dissolved, but wouldn't also dissolve the first spraypaint layer. Just a thought, though.

But, if it doesn't dissolve paint, it can't get get to the temporary layer underneath....
We may have to keep brainstorming.  A similar idea I had was to do a normal etch/paint/sand then apply something that paint won't stick to and sand again then repaint.  But, if paint won't stick to it, it probably wouldn't stick to the paint....

[EBK]

I've had some light success just coloring it in with an ink marker (Sharpie) then using a sanding block to remove any places I "went outside the lines".

That does give me an idea.  What if I replaced the sanding block with a damp sponge?  Paint box, let dry, apply paint or ink to etched areas, then wipe off excess.  Maybe.

[deadlyshart]

ironically

WHY MUST YOU DO THIS TO ME

No idea. 

Anyway, I think there are a couple ways this could maybe be done, though I haven't tried any myself.

One way: Do a fairly deep etch. Do the first paint color really thick (several coats), and the second color very thin, one coat. You start sanding, and because the first layer is really thick, you should be able to stop when the top layer has been sanded off, but the second layer is still there (on the embossed areas that would normally get sanded down to the metal). The recessed areas will still have the top paint layer.

If you think carefully about this, the end result would be indistinguishable from a decal.  NM, I think I misunderstood which layer was first/second/top.Still, not too sure I want a thick coat in the engraved areas.

Another way (maybe?), though it would only allow you to get black as the 2nd color, would be to do the normal process, but after the bare metal is produced, do a very brief ferric chloride etch, which normally turns the Al black. It seems like organics are pretty resistant to the acid, so the spray paint (other color) would probably be unhurt by it. This would let you get black + other color.

Interesting.  I wouldn't mind finding out what that would look like.

Another possible way, though this is very speculative. You do the normal process, spray paint 1st color, sand off paint from embossed areas. You apply another easily dissolved layer (nail polish?) over the whole thing, let dry. You then sand off embossed areas again, then spray paint second color. The second color will end up directly on the metal of the embossed areas, and on top of the temporary layer for the recessed areas. You let it dry, then dissolve that temporary layer in a solvent. This method might be tricky/impossible because it might be hard to find something that could be dissolved, but wouldn't also dissolve the first spraypaint layer. Just a thought, though.

But, if it doesn't dissolve paint, it can't get get to the temporary layer underneath....
We may have to keep brainstorming.  A similar idea I had was to do a normal etch/paint/sand then apply something that paint won't stick to and sand again then repaint.  But, if paint won't stick to it, it probably wouldn't stick to the paint....

Hmm. How would a thick coat be distinguishable from a thin coat, in the engraved areas?

I know what you mean, but I don't think you'd need to worry about "getting to" the temp layer underneath... if it's truly dissolvable, any sort of opening will "access" it and go underneath.

To be honest, I'm basing several of these ideas of processes I do at work for microfabrication, because they're almost perfectly analogous (except several thousand/million times bigger  ). For example:

[deadastronaut]

i re-read your initial post...

as its your first, keep it simple....get 1 done properly , ...then experiment,

many mess up their first etch...some dont.

[EBK]

i re-read your initial post...

as its your first, keep it simple....get 1 done properly , ...then experiment,

many mess up their first etch...some dont.

I'm definitely not going to rush it.  In fact, I have the perfect piece of scrap for my first attempt(s).  I bought a really shoddy Taiwanese powder coated box (I won't say from whom) that was supposed to be red, but was instead a really streaky color that the drummer in my band referred to as "80's prostitute pink".  It's drilled out for 4 knobs and I have nothing in my potential build queue that needs that.  I'm looking forward to sanding that down, and anything I do can only make it look better.

[davent]

Is the etched area painted as well or left as a bare etched surface?

dave

[EBK]

Is the etched area painted as well or left as a bare etched surface?

dave

Thinking about painting the etched area too.