Has anyone tried spray paint on foam sheets?

muppetperson

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I have some thin sponge sheet foam that I want to paint, using a can of spray paint,
but I don't know if it might dissolve the foam like Styrofoam. I only have the actual parts
so I cant do a test. Has anyone tried this before?
 

crazy chris

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I spray painted some foam bricks with a textured paint from lowes and they were rock solid... no pun intended... im pretty sure styrofoams is a completely different fiber than your basic foam

cc
 

muppetperson

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I spray painted some foam bricks with a textured paint from lowes and they were rock solid... no pun intended... im pretty sure styrofoams is a completely different fiber than your basic foam

cc
I have just found a trick of painting Styrofoam with ordinary spray paint. the trick is to spray about 30cm away, and it wont dissolve the foam. So that is what I have done on my thin sponge foam to be safe, and it worked. Apparently if you spray close up, the paint comes out of the can very cold, which causes the damage, but if you keep it away 30cm, then by the time it gets to the surface, it has warmed up a bit.:wisdom:
 

crazy chris

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I have just found a trick of painting Styrofoam with ordinary spray paint. the trick is to spray about 30cm away, and it wont dissolve the foam. So that is what I have done on my thin sponge foam to be safe, and it worked. Apparently if you spray close up, the paint comes out of the can very cold, which causes the damage, but if you keep it away 30cm, then by the time it gets to the surface, it has warmed up a bit.:wisdom:
AWESOME TIP!!!

cc
 

Buck-Beaver

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I have just found a trick of painting Styrofoam with ordinary spray paint. the trick is to spray about 30cm away, and it wont dissolve the foam. So that is what I have done on my thin sponge foam to be safe, and it worked. Apparently if you spray close up, the paint comes out of the can very cold, which causes the damage, but if you keep it away 30cm, then by the time it gets to the surface, it has warmed up a bit.
That would defy some basic principles in chemistry (did you get that from this video on Youtube by any chance?).

Heat causes styrofoam to melt, not cold (when you think about, when does something ever melt in the cold? Also, how would the paint stay cold in the can without refrigeration or some kind of coolant?). The chemical reaction between the propellant in the paint (which is a solvent, usually acetone I think) and polystyrene (in the Styrofoam) is what causes the Styrofoam to dissolve.

The trick does work, but because holding the can far enough away from the styrofoam allows the solvent to dissipate in the air (most spray cans actually explicitly tell people to do this, but few of us ever bother to read the instructions).

Another great trick is to coat the object with one or two coats of PVA (white) glue which forms a clear barrier that protects the surface from the solvent in the paint.

Science! :wisdom:
 
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muppetperson

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That would defy some basic principles in chemistry (did you get that from this video on Youtube by any chance?).

Heat causes styrofoam to melt, not cold (when you think about, when does something ever melt in the cold? Also, how would the paint stay cold in the can without refrigeration or some kind of coolant?). The chemical reaction between the propellant in the paint (which is a solvent, usually acetone I think) and polystyrene (in the Styrofoam) is what causes the Styrofoam to dissolve.

The trick does work, but because holding the can far enough away from the styrofoam allows the solvent to dissipate in the air (most spray cans actually explicitly tell people to do this, but few of us ever bother to read the instructions).

Another great trick is to coat the object with one or two coats of PVA (white) glue which forms a clear barrier that protects the surface from the solvent in the paint.

Science! :wisdom:
yes, that is the source! I tended to believe the reason, because when I first use shaving foam, it comes out really cold, with the gas release, and like dry ice where you have extreme cold, things start to boil! But thanks for clearing it up and your extra tip.
 

Buck-Beaver

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You can also use an air brush, which will change your (artistic) life. It's a bit of an up front investment, but you get so much more control and it will save you a lot of money in the long run.
 

practicecactus

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Also bear in mind how porous the foam is/it's density. All those little bubbles that make up the foam are gonna be even more obvious with lighter colour paints because they'll make lots of little shadows. I made a beak out of foam and then got a wonderful smooth, almost rubber, finish on it by applying about fifteen coats of water based craft paint and sanding it.

Aways use a small test piece to see what it does before doing the real deal.
 

cjspiteri

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With an airbrush are you limited to a particular type of paint? I've never used one and would like to keep using acrylics and tempra if possible.
 
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