can you use paint not recommended for plastics?

[foxbat426]

OK I know this might sounds like a stupid question and i might be answering my own question.

I'm on my third build and found the perfect color paint for my 69 monogram GTO Judge. It's Krylon farm and implement paint and its says its for wood and metal, but never mentions for use with plastic on the can.

I'm a good can sprayer, but no matter how I tried with my wet coats, they would always start out perfect, but as they dried i would keep getting orange peel on the finish. I DID NOT use primer.

I finally gave up and started taking the paint off with 90% rubbing alcohol and when i got to the actual plastic it was all orange peeled and pitted with a very rough surface. Thankfully i only sprayed the hood.

my question is did the paint do this?? I guess obviously it did, but next time if i primer before hand can i use a can spray paint that is not specified for plastic??

Thanks, john

[Tom Geiger]

John, automotive paints like Duplicolor will also affect the plastic. Putting on a good coat of Duplicolor primer will protect the plastic from HOT paint. Try that if you want to give that paint a second try.

[Erik Smith]

Yes, the paint more than likely did that. A lot of those paints - Krylon, etc, even ones labeled "enamel" - will craze plastic. Use a good primer and it will keep the "hot" paint from the plastic. You may still encounter some issues, I have had mixed results with hardware store paints - some I like, others dry weird or do other odd things.

[1930fordpickup]

If you have some spar parts try painting that first . You could use some sprue from the same kit for a trail. Just clean with soap and water before you put the primer on .

[Modelbuilder Mark]

The simple answer to your question is yes, you can use all sorts of stuff. Automotive paint, craft paint, fingernail polish etc etc. Just test spare sprue if you can as others have suggested, and try to create that barrier using a good primer. There are several things you can try like the duplicolor primer, or several sold just for the hobby, you can also use a self etching barrier primer like Variprime two part but that is expensive. I know some folks even try to use Future as a barrier, although I have never tried that and would be hesitant to.

[foxbat426]

Thanks everyone. I got away without using primer on my first two builds, now i'm going to start using it.

Next question - does the color of the primer matter?? I know there is white, gray, black, red and i think green primers. is it necessary to use a certain primer color depending on body color?? Thank-you again and great info!

John

[Pete J.]

Colored primer has a purpose. There are some colors of paints that are translucent and the color of the primer will most definitely effect the final look. Red and Yellow are the ones you want to be especially careful with. It is best to spray a test piece first. On the same subject but with a different slant, Ferrari used different primers for Ferrari Red. If they use an orange primer the red has more of a florescent cast. Most of their stuff has a pink primer. Never, ever use gray primer under either red or yellow. It absolutely kills the color. Blacks and very dark colors, not so much. So in a word, does the color of the primer matter? Yes!

[Tom Geiger]

Thanks everyone. I got away without using primer on my first two builds, now i'm going to start using it.

Next question - does the color of the primer matter?? I know there is white, gray, black, red and i think green primers. is it necessary to use a certain primer color depending on body color?? Thank-you again and great info!

the primer you use under your color coat can affect the tone of your final color. Some folks use different colors to tone the paint to their liking. Go to the grocery store and get yourself a pack of white plastic spoons. Experiment with them. First take your intended color and spray it right on the white spoon. Then with each subsequent spoon, try a different base under your paint. Gray primer, red oxide, and even gold and silver paint. Once your color coat dries on the spoons, you will have 6 different colors.

[Aaronw]

Not all plastics are the same either, so a safe paint on one kit may ruin another. It is always safest to use a primer.

Colored primer has a purpose. There are some colors of paints that are translucent and the color of the primer will most definitely effect the final look. Red and Yellow are the ones you want to be especially careful with. It is best to spray a test piece first. On the same subject but with a different slant, Ferrari used different primers for Ferrari Red. If they use an orange primer the red has more of a florescent cast. Most of their stuff has a pink primer. Never, ever use gray primer under either red or yellow. It absolutely kills the color. Blacks and very dark colors, not so much. So in a word, does the color of the primer matter? Yes!

You are correct, but sometimes that is the point. I use grey primer under yellow and red when I want to mute the brightness, knock a bright sunshine yellow down to a utilitarian dump truck yellow.

[Pete J.]

You are correct, but sometimes that is the point. I use grey primer under yellow and red when I want to mute the brightness, knock a bright sunshine yellow down to a utilitarian dump truck yellow.

Hmmmm.... never though of using it that way, but good point. I have screwed up a couple of red or yellow sports cars with gray primer. I will store this in the vault of potentially useful information.