[tms9918]

I have some abs plastic to which nail polish was applied, and I would like to remove it, possibly with household items.
I am wondering that acetone would liquefy the top layer of the plastic

[Corribus]

Acetone and ABS do not get along.

https://www.plasticsintl.com/chemical-resistance-chart

You may use that chart as a guide to compatible solvents.

What you might want to try is diluting Acetone in some water. Use a Q-tip or something soaked in that solution and gently apply to the area of nail polish only.  If no nail polish comes off, increase concentration of acetone until you see an effect. If you are careful only to touch the nail polish, you can probably succeed in removing most of it without damaging the plastic underneath.

Alcohols - ethanol or isopropanol - will also remove polish. It takes a while and you are less likely to damage the ABS underneath.

You could also try mechanical detergent, like scrubbing with toothpaste. But you could also slightly abrade the polymer underneath.

[Babcock_Hall]

http://cs.finescale.com/fsm/general_discussion/f/9/t/164010.aspx
https://www.dakkadakka.com/dakkaforum/posts/list/370207.page

Ordinary plastic used for model cars and planes sometimes needs to be stripped and repainted.  Simple Green and Purple Power are sometimes used ( see links above).  I think I used Purple Power twice, and it worked just fine.  Two caveats.  One is that most plastic models are made out of polystyrene, not ABS (acrylonitrile butadiene styrene).  Two is that acrylic or modeling paint may be a different story vs. nail polish.  Do you have any scrap plastic that could be used as a test?

[Corribus]

Sounds like someone's kids painted their prized Legos with nail polish

[tms9918]

Thank you Corribus and Babcock_Hall. It's not Legos, it's a Sega Saturn which was vandalized   
I will try with IPA and ethanol. I would love to try purple power, but I live out of the US.
What ingredients should I look for to find equivalents? Are Ethylene Glycol or Monobutyl Ether important?

[Corribus]

Basically, you're just looking for a solvent that dissolves the polish but not the underlying substrate. Nail polish is basically an organic polymer, like nitrocellulose, dissolved in a volatile solvent, such as ethyl acetate. When the underlying substrate is a polymer, finding a suitable solvent that dissolves the polish polymer without dissolving the substrate polymer can be challenging. Acetone is a very aggressive solvent, which makes it a poor choice because it will dissolve both polymers rapidly. Alcohols are not as good at dissolving polymers in the polish, but neither are they good at dissolving the substrate. Therefore it takes a bit (lot) more work, but you stand a better chance at removing the surface polymer without significantly damaging the polymer underneath. I would start with isopropanol (rubbing alcohol) and see where that gets you. You may also seek out "acetone free nail polish remover". These removers usually have ethyl acetate in them in place of the acetone. The ethyl acetate is a gentler solvent and so will take longer to dissolve (and damage) the underlying substrate, while still removing the surface nail polish. Based on the solubility chart, ABS has better compatibility with isopropanol than ethyl acetate, so it is the safer choice as far as your ABS substrate is concerned... but it may be very inefficient at removing your polish. It all depends on what kind of polish you have on there.

Hope that helps. I personally would try rubbing alcohol first. If no luck, find a non-acetone remover and carefully try to remove the polish without getting the underlying substrate. You should be prepared to accept some surface damage to the ABS, though - the polish itself contained ethyl acetate or some other solvent that probably damaged the ABS surface when it was applied.

[tms9918]

Thank you very much, I'll go with IPA then!

[Enthalpy]

Remove all electronics before.

IPA isn't very bad for electronic boards, but other solvents are, and traces of pollutants can cause malfunction, especially those in water. In a computer, they could empty the so-called Cmos battery faster than normal.

[tms9918]

thank you for the suggestion. I will indeed remove the plastic shell before starting the work.
I usually use IPA for removing the flux out of PCBs, but better safe then sorry!