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I have a couple of roughly fist-sized plastic pieces that I'd like to paint (I'll post a pic as soon as I can); preferably with a spray but brush is OK too.

First I intend to lay down a primer (for this material any ABS / styrene primer will do, and I know at least Montana and Tamiya brand plastic primers definitely work). Then I'm going to paint. Solid color, no fine details.

The thing is, this plastic is mildly flexible. It's not straight up bendy or squishy, but it's more like a really stiff rubber, like the kind of stuff you might see used as feet for cheap metal furniture (that's the only example I can think of). It's got a "softness" to it like... you feel like you will be able to bend it but you kind of can't, if that makes sense. So it's not going to be all over the place but it is not perfectly rigid.

Because of that, I'm worried that an enamel paint (it's all I'm really familiar with besides "latex", as I usually work with metal and wood) will start to crack and chip fairly quickly. I've also got my fingers crossed that the primer won't do the same thing, since I have zero experience with it.

Anyways, that was a super long-winded way of saying: What kind of paint can I use? It's got to have some pliability / elasticity when dry, and should at least be compatible with whatever ABS / styrene primers are made out of. Also, the pieces won't be handled super roughly but they will definitely get handled frequently, so it's got to be at least somewhat durable.

Bonus points if it blocks UV, but that's really just icing on the cake (also the primer might, not sure, will have to look it up).


It's actually resin, not plastic. Specifically it's FormLabs Durable resin off an SLA printer, and the pieces are thick enough to make it rather stiff. But ABS primers are manufacturer recommended so it's simpler just to say plastic here (I mean, it's a polymer at least). It's mechanically closer to a polyethylene or polypropylene plastic, and chemically closer to ABS, than it is to a polyester or polyurethane resin.

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    Acrylic might work. Another option might be one of the rubberized coatings, which remain very flexible and giving (although they tend to go on thick, which would hide surface detail). I'll leave this as a comment since it's just speculation.
    – fixer1234
    Commented Mar 28, 2021 at 22:46
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    I think acrylic will chip off at some point on a semi-flexible surface. If you take that route, at least sand the surface with fine sand paper before applying it. Maybe grounding with a thin layer can also increase longevity.
    – Joachim
    Commented Mar 29, 2021 at 9:05
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    I've seen plenty of examples of people using acrylic craft and/or miniature paints on 3D printed resin; I'd guess, based on that, that acrylic would be your best bet.
    – Allison C
    Commented Mar 29, 2021 at 14:39
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    Huh. It doesn't seem to matter at all. Both the enamels and the acrylics (and the primer I tried, although it was not specialty plastic primer, it was some all-purpose stuff I had on hand) handle the flex completely fine (noting that none of them bind particularly well to the test material, which gives them even less support under flex, which is good for this test). Maybe I overthought the paint choice. I'll post an answer tomorrow, I want to give it another 24 hours or so first and check again. Fwiw, btw, I don't actually know if it's plexiglass; it's just some scrap of something. 🤷‍♂️
    – Jason C
    Commented Mar 30, 2021 at 18:07
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    There is still the matter of longevity, though. In this time frame, oil paints would probably also still flex along with the material. "Don't overthink it" is for those who don't want to overthink it - for others, more information/data might be required :)
    – Joachim
    Commented Nov 10, 2021 at 9:51

1 Answer 1

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Elastomeric paint

And the asnwer you are looking for...

Acrylic Paint

Acrylic paint is indeed very elastic, as the comment section points out: It prevents cracking from occurring.

Other Options

There arent really 'other options that doesn't contain acrylic based paints... one of them is called: Urethane, this bad boy is basically modified acrylic paint.

Elastomeric paint

Would be your final answer

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  • The elastomeric paint I'm familiar with is designed for exterior masonry surfaces. It's extremely thick. If that's the stuff referred to, it would likely adhere to the primer, but would hide surface detail. From the question, it sounds more like the plastic is a little soft and "dentable", but not really flexible. Elastomeric paint might be overkill, but it might be possible to thin it to be more like normal paint. If it's sold as exterior masonry paint, it's probably in large (expensive) containers and maybe limited color choices, rather than small bottles of "model" paint.
    – fixer1234
    Commented Dec 25, 2022 at 20:08

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