Hello, I hope you guys can give me some advice here. I have a warmoth body that I grain filled and primed. I am using montana spraypaint and after I gave it a few coats it turned into a powdery substance and i could brush the paint of with my finger. when I tried to sand it it turned into a red color and the paint is brown(latte). At first I thought it was just a bad can until I got the same results from another can. Thanks for the help.
Paint is turning to powder!
- Thread starter beyondat
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Tonar8352
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It could be several things but bear with me and answer some questions so I can narrow it down.
What primer did you use? Was it the recommended primer for the finish product?
What was the time frame for it to start failing on you?
Did you use any thinners and if so what were they?
What kind of paint is it, Acrylic, Lacquer, or Alkyd?
Spray Paint, do you mean in an aerosol spray can?
What was the weather conditions when it was sprayed and left to dry? In other words did it get sprayed outside in the cold and hung in a warm room or vies a versa.
Are there batch numbers on the cans and do they match?
Let me know I might be able to give you an idea of what is going on.
What primer did you use? Was it the recommended primer for the finish product?
What was the time frame for it to start failing on you?
Did you use any thinners and if so what were they?
What kind of paint is it, Acrylic, Lacquer, or Alkyd?
Spray Paint, do you mean in an aerosol spray can?
What was the weather conditions when it was sprayed and left to dry? In other words did it get sprayed outside in the cold and hung in a warm room or vies a versa.
Are there batch numbers on the cans and do they match?
Let me know I might be able to give you an idea of what is going on.
Cagey
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All good questions, but if it's lacquer I'd be suspicious of the spraying distance first. That stuff will practically dry in mid-air, especially from a rattle can. Acetone boils off at a pretty low temperature. If you shoot from too far, you're basically just dusting the target with dyed cellulose solids.
Tonar8352
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In order to determine if it is surface problems try shooting some of the paint on another surface. If it does not do it on the different surface then there is something on the surface that is causing it to react the way it is. If it does the same thigh on a different surface then there is a good chance that you have a bad batch of material. Call the manufacture and they can check batch records and will know if is good or bad.
Generally when paint turns to powder it is cause by oxidization but that happens over a period of time and generally on oil based paints or epoxy primers. The other reason that paint can powder up is that the resins are not properly wrapping the pigment during the curing process. That would be highly unlikely with Lacquer but could be possible if it is not properly agitated.
There is a possibility that the pigment load is to heavy for the amount of resin but that generally shows op with what is called color float. The pigment will not properly disperse in the base so it will come to the surface in its raw form i.e. you will see an bright red floating to the top of the surface of a orange color. The way to test for this is to shoot some on a slick surface and then rub it with your finger. If the pigment load is too heavy the color will “rub up” or change immediately to a darker color usally.
Hope that helps.
Generally when paint turns to powder it is cause by oxidization but that happens over a period of time and generally on oil based paints or epoxy primers. The other reason that paint can powder up is that the resins are not properly wrapping the pigment during the curing process. That would be highly unlikely with Lacquer but could be possible if it is not properly agitated.
There is a possibility that the pigment load is to heavy for the amount of resin but that generally shows op with what is called color float. The pigment will not properly disperse in the base so it will come to the surface in its raw form i.e. you will see an bright red floating to the top of the surface of a orange color. The way to test for this is to shoot some on a slick surface and then rub it with your finger. If the pigment load is too heavy the color will “rub up” or change immediately to a darker color usally.
Hope that helps.
