muriatic acid/peroxide etchant + ACRYLIC Plexiglass

[burningman]

Is muriatic acid/peroxide etchant safe to use in an acrylic (plexiglass) diy tank, or will it eat away at it? 
I'm also wondering if anyone knows of a sealant/adhesive that could deal with being submerged in the muriatic...etchant?
Thanks.

[sean k]

As soon as I saw the post I hoped it would be unsafe  as in it'd be great to etch acrylic... I don't know but the idea would be to make up some and chuck it in. Alien the movie has given us some funny ideas about the possible strengths of Acids but I doubt you'll unknowingly make an extremely explosive mixture by trial and error. The fibreglass on the back of the copper is most probably made using an acrylic resin as opposed to epoxy so ... try a blob of silicone in the mix, see what happens.

[juse]

FR-4 is woven glass & epoxy resin.....

[burningman]

I'll probably scrap the hcl etchant idea.
My question is now whether I should use Amonium or Sodium persulphate. Any suggestions?

[juse]

How big are the boards you are etching? If you cut them to size first, you can use a glass jar for your tank... something like an instant coffee jar - these usually have a wide mouth. I prefer the muriatic/peroxide etchant....... easy & cheap.

[burningman]

The boards will vary. I would probably just use the glass/plastic jar but I might be doing boards upwards of 18" in length.
Are there any differences/benefits between using amonium vs sodium persulphate?

[aziltz]

18" 


whoa.

[juse]

Are there any differences/benefits between using amonium vs sodium persulphate?

Sodium Persulfate:
-Expensive
-One of the more environmentaly friendly etchants
-Recommended as a replacement for Amonium Persulfate
-Works with etch resist pens
-Usually hard to find

Amonium Persulfate:
-Expensive
-Hard to control the etching process
-Needs an agitation tank because the excessive bubbles produced keep the AP from properly etching
-Needs to be heated, has low efficiency at room temperature
-Has a short shelf life once opened

Hydrochloric acid & hydrogen peroxide:
-Cheap   (I just bought a 1 gallon jug for $6 USD)
-Hydrochloric (muriatic) acid is easily found in most home & garden centers or anywhere that sells swimming pool supplies
-Etch bath doesn't need to be heated
-Doesn't need an agitation tank
-Can be used almost indefinitely    http://www.instructables.com/id/Stop-using-Ferric-Chloride-etchant!--A-better-etc/


You can't tell I'm biased, can you? 


If you are going to be etching 18" boards, you might find a long, rectangular tupperware dish or one of those plastic storage crates and lay it in a shallow bath of *cough* muriatic acid/hydrogen peroxide......

[humptydumpty]

They sell the long storage crates, the plastic ones, about 4 or so feet long by about 2 feet wide at wal mart for about 5-7 bucks

they are, to my recollection, about 6 or so inches deep

[synthmonger]

I'd go with the hydrochloric acid & h2O2 mix. One thing to make sure is you need to agitate the board during the etching process. It should take 3-10 minutes depending on your board size. Most of mine are about 3x4 which take 5 minutes.

You can reuse the mixture too. You'll get a nice turquoise/green coloration afterwards!

You can pick up a jug of acid just about anywhere. I got mine at Ace Hardware for a few bucks. I'm disposing of my old ferric chloride as soon as I can find a local recycler.

[burningman]

Thank you for all the suggestions.
With regards to the HCL H202 mix - what should the ratio's be for boards? How would you reuse (add more hcl)?
thanks.

[juse]

Read this, it sums it up pretty good:

http://www.instructables.com/id/Stop-using-Ferric-Chloride-etchant!--A-better-etc/

[David]

Is muriatic acid/peroxide etchant safe to use in an acrylic (plexiglass) diy tank, or will it eat away at it? 
I'm also wondering if anyone knows of a sealant/adhesive that could deal with being submerged in the muriatic...etchant?
Thanks.

I've been etching PCBs in the same plastic margarine dish since 2004.  What does that tell you?

Oh, by the way, don't bother with the "medicinal" hydrogen peroxide.  Swallow your pride, go to a beauty supply store and get 30% or even 40% hydrogen peroxide solution.  You'll etch a 2-inch by 2-inch square in 30 seconds.  Move the board in the solution with plastic forceps.  Dude, you can SEE the copper come off!