I have not experimented with this in several years. Back then I tried a couple of different things. One was an epoxy paint after I roughed up the surface. That was not worth the effort.
I also tried a spray-on flash primer that I had previously used on glass. That worked pretty well. You spray the primer on first and then use whatever paint you like.
Krylon now has a spray paint specifically made for plastic. I think that would probably work but I can't guarantee how long it would last.
I'd try that first.
>>I'm planning to convert a pre-fabricated melamine storage cabinet into three units to hold arboreal boas. I'm going oto waterproof the inside with Contact paper and silicone sealant, but would like to paint the outside with something other than the melamine white color. Will paint stick? Anybody have any experience with trying this?
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Current snakes:
1.1 Gonyosoma oxycephala - (Silver/Yellow)
3.4 Gonyosoma oxycephala - (Green)
2.1 Gonyosoma janseni - (Black)