Bendy plastic that won't take paint?

[Too Bo Coo]

Try Krylon Fusion for the base coat and highlight from there.  It has a mild solvent in it and it adheres to any plastic that I have used it on.  http://www.krylon.com/products/fusion-for-plastic/
Hope that helps.

I second this.  If I'm correct, this was a product developed by/for the auto industry so that they can make plastic coated parts easier.  Your problem seems to be that the paint forms a shell that does not bond to the plastic, so that when the plastic moves, the 'shell' does not move with it and actually works its way off.  It's not bonding. 

Hard plastics, and even metal, should be washed because of the release agent, but that does not sound like your case.  It's the chemical composition of the plastic and I agree with the Krylon solution.

[former user]

There is also a hardening agent you can brush on. A friend of a friend uses it on his extensive 1/72nd collection. It is expensive, smelly, and hard to find though.

and how ist it called or what does it consist of?

[maxxon]

I tried the PVA trick on some cheap and nasty sontaran figures I got.

My experience is that the PVA does not bond to the figure either, but instead it forms a complete shell that is somewhat more resistant to flaking then just plain paint.

If you get a nick in the PVA, the whole thing just flakes off and you're better recoating entirely.

[DS615]

Wash them, prime them, then seal them when done.
I have dozens and dozens painted that way, and they are fine.

[Mindenbrush]

I had already posted this in another thread but it looks like it could solve your problem:

I have some plastic dino's to paint and a friend of mine who is using nothing but 'bendy' plastics these days recommends spraying the plastic figures / animals with Aleene's Tacky Glue which does dry and then a coating of Krylon Fusion for Plastic.

[Archie]

While this might not be exactly the same issue, I've tried painting the bases of the collectable DnD minis and found that if I don't spray a couple of coats of clear finish on first, the paint doesn't cover very well. It has to do with the kind of chemicals/oils that are in the plastic that the minis are cast from. You end up getting a tacky/sticky finish that you can't paint over and never really stops being tacky, if you don't spray the clear coat first.

I'm wondering if you did the same with your animals if it would work. I don't remember exactly which paint I used, but more than likely it was testor's clear coat.

I have quite a collection of DnD figures and I have just started to paint the bases and add flock etc. I cant say I have had any issues with paint sticking. I'm using the most recent version of GW paint and also some Remmill paints.

[Silent Invader]

Have you tried giving one a good coat of thin superglue - well ventilated of course?

[bishop odo]

Reaper Bones have that same problem, the Krylon acting as a primer works.

I have had the same problem with WOTC Star Wars figures.  So I pick out the best, usually humans or near humans with a head swap, for Traveller,  cast them up in resin.  This way I can carve and an add detail, swap, sculpt to my own content.  Is it cheap? No but considering the cost of the figure in the first place, its ok, beside I'm into quality.  My next little project is a home made spin caster. 

I did an experiment years ago trying to strip some prepainted plastic and I found that brush cleaner, stiffens the plastic by almost 50%, not enough for me to stop the casting, but FIY.

[Archie]

Just read today about soaking plastic figures in white vinegar to very slightly etch the surface for better paint adhesion.  Anyone ever tried that?