How to remove acrylic paint from a specific area(without damaging the lacquer under)?

Might try an ammonia type glass cleaner like liquid Windex on Q-tips.

General consensus is yeah, thinning in the bottle tends to shorten lifespan of paint in the bottle.

How do I know when the paint is not useable anymore?

berd

I need to remove some acrylic paint from the side skrits of a panzer IV which is attached to the model and base coated in a lacquer paint how would i accomplish this?

thanks

berd

also does thinning paint in the jar shorten life?

thanks

Some say yes some say no.

I have 30+ year old sealed Large Tamiya acrylic & Humbrol enamels, still good.

I completely mix my paints in the pot with a cocktail stirrer/Humbrol paint stirrer.

Then I decant some/enough into a smaller airtight pot, such as cleaned small tamiya pots or a 35mm film canister or flip top container.

Then I thin it, & only then, do I put a little in the airbrush to test, adjusting to suit.

As I mostly use Mr Hobby Levelling thinner, Tamiya pink top lacquer thinner or acrylic thinners, these are more volatile than the neat paint, and can go 'off' but can be 'refreshed' with a little more thinner.

Key point is that I mix enough for the job, & any leftover goes into the sealable container, and is good for the length of the build, weeks, more often months.

berd

How do I know when the paint is not useable anymore?

 

1 It separated and doesn't seem to stir back together uniformly, forming lumps or clumps. At any rate not creamy. Some paints have natural sediment but it will mix back in, that's normal for that kind of paint. I'm talking about an unmanagable consistency.

2 It thickened into glop or turned rubbery. Toss it out.

4 It just plain dried up. Again toss it.

5 If acrylic paint got frozen it's generally ruined.

Generally speaking:

Otherwise from the above you can probably thin it and use it. Keep the container rim and lid and threads clean so the lid seals right when put back on. Most ruined paint is because air got to it for too long or when stored. I draw my paint out using pipettes rather than pouring, sometimes even with dropper bottles rather than dripping through the top. Depends on the paint.

I'll put my vote in for an ammonia based cleaner like Windex.  Don't use isopropyl alcohol though...its what I use when I really screw something up and want to strip things down to bare plastic.  It removes lacquers too...even Tamiya primer.