Some Info About Painting With Enamel.
Hey guys, I just wanted to share my findings with you on enamel paint.
I've been painting the dash bezels in my Duster. I'm using Rustoleum flat black enamel. They've been painted for about 5 days now. I did all the proper prepping, including spraying adhesion promoter on the plastic beforehand. I went to go do my scratch test today (the rattle can said it would take 5 days to cure) sure enough, it scraped right off. The enamel is soft and tacky. My heart sank. :(
Heres the difference in Lacquer and Enamel so the rest of this makes sense:
If you spray enamel on too thick the top will dry and prevent oxygen from getting below to the still uncured enamel. Once this happens the enamel underneath can not cure (or will cure extremely slowly, possibly years) because the oxidative cross-linking can no longer occur. You will always have soft paint under a thin hard shell when this happens. Which I hope I didn't do.:angry7:
In all truth enamel takes 15-30 days or even a year to cure hard. Not what the can said (5 days). So don't necessarily give up if it's not dry in the time the can says.
The best way to apply enamel is in VERY VERY VERY THIN coats. I mean seriously thin coats. This way a lot of the paint is exposed to oxygen and can begin the curing process. This way your project can turn out rock hard.
We'll see if mine dries in a month... I'm really hoping it does and I didn't spray it too thick. I'll let you all know what happens.
Also a MUST for painting plastic is to use an adhesion promoter!
This may be common knowledge. So sorry if I'm just rehashing something you all know. I just thought I would share my findings in case any of you are having issues with this. Hopefully this info can alleviate some of your frustrations.](*,)
Cheers,
Drake
Hey guys, I just wanted to share my findings with you on enamel paint.
I've been painting the dash bezels in my Duster. I'm using Rustoleum flat black enamel. They've been painted for about 5 days now. I did all the proper prepping, including spraying adhesion promoter on the plastic beforehand. I went to go do my scratch test today (the rattle can said it would take 5 days to cure) sure enough, it scraped right off. The enamel is soft and tacky. My heart sank. :(
Heres the difference in Lacquer and Enamel so the rest of this makes sense:
- Lacquers truly do dry. The solvents in them evaporate out, thus drying it.
- Enamels (without a hardener, Rustoleum for example) cure, they don't "dry". It cures (hardens) by a chemical reaction called oxidative cross-linking. The binder is hardened molecularly due to exposure to oxygen.
If you spray enamel on too thick the top will dry and prevent oxygen from getting below to the still uncured enamel. Once this happens the enamel underneath can not cure (or will cure extremely slowly, possibly years) because the oxidative cross-linking can no longer occur. You will always have soft paint under a thin hard shell when this happens. Which I hope I didn't do.:angry7:
In all truth enamel takes 15-30 days or even a year to cure hard. Not what the can said (5 days). So don't necessarily give up if it's not dry in the time the can says.
The best way to apply enamel is in VERY VERY VERY THIN coats. I mean seriously thin coats. This way a lot of the paint is exposed to oxygen and can begin the curing process. This way your project can turn out rock hard.
We'll see if mine dries in a month... I'm really hoping it does and I didn't spray it too thick. I'll let you all know what happens.
Also a MUST for painting plastic is to use an adhesion promoter!
This may be common knowledge. So sorry if I'm just rehashing something you all know. I just thought I would share my findings in case any of you are having issues with this. Hopefully this info can alleviate some of your frustrations.](*,)
Cheers,
Drake