Whats the best way to paint pink insulation foam?

Im trying to make something out of that pink insulation foam. I carved the pieces from it, and used wood putty to fill in the cracks and really rough places.





the problem is, when i try to paint it yellow like i want, the wood putty takes the color differently than the foam, so it looks.....odd.





also, i can't use a glaze in place of the putty because it dissolves the foam and looks terrible. how am i going to do this?

Whats the best way to paint pink insulation foam?
Get a water based primer sealer. Apply one or two coats to seal and prime the foam and the wood filler. Sand lightly between coats, and dust off. then, once the primer is dry, paint it yellow! DO NOT use an oil based primer, as it will attack the petroleum base of the foam!!
Reply:Use a primer so that both surfaces are uniform then apply the paint. The foam is what is causing the problem because of the density in the foam is quite different then the wood. Do not try to paint a thick layer on top of the foam as this will make it look terrible. Using layers of paint is much less obvious when two surfaces are so close to each other.
Reply:do not use a putty. use a lightweight drywall crack filler and prime with a water based primer and then topcoat with a latex paint. color and sheen are up to you.
Reply:Don't use the putty, that is for much smaller cracks and holes, use plaster , dry then sand then primer then paint.
Reply:Spray the putty down with Poly Urethane sealer first and then spray paint, There is a paint out for wood and Plastic that should work great for you.
Reply:Go to your local Hobby Shop and ask the clerk to show you some yellow low heat shrink plastic covering. This stuff is fantastic. We use it exclusively when we build radio controlled model airplanes.





You can put it on the pink foam and have a shiny smooth stuck tight surface. It can be used to cover compound curves, to some extent, but if your project is a carved surface with a 3-D effect, it will not cover that.