Advice on painting an unpainted plastic part

[93civej1]

So, I have a part that came to me today that is unpainted just bare black plastic. I ordered a rattle can from mopar of my Gobi paint. I am wanting to paint this part, but am wondering what is the best process to get it looking its best?

Scuff up the plastic with some sand paper? What grit?
Spray parts with some sort of primer for adhesion? What kind of primer if so and brand? how many coats?
Spray parts with Gobi Mopar paint? How many coats? Any sanding between or after coats? If so, how many? Wet? What Grit?
Spray final with clear coat. What kind / brand? How many coats? Any sanding between or after coats? If so, how many? Wet? What Grit?
Polish and wax parts for final?

Paining some upainted grille parts that i want to make match my paint color, but I want it to look good.

Sponsored

 

[93civej1]

Anyone familiar with this process? I can do it, just wanna make sure I do it to the best of my abilities and make it look decent.

 

[Rockabillyroy]

i painted my plastic strike force zebra doors. sanded it down, coated it with primer. Not a big deal, but what really put it over the top was this stuff.

https://www.amazon.com/Spray-High-Gloss-Clearcoat-Aerosol/dp/B00W2D806Y/

It's amazing. I tried chrysler clear coat and it didn't even look close. A single coat of this and it was a world of difference. A few more coats and those doors held on to their shine up until I sold them.

 

[spectre6000]

Scuffing may or may not be necessary and may even be counterproductive. Prep and primer will be your most important factors. Make sure there is zero silicone (huge on plastic parts) or grease. The silicone will cause fisheyes, and it's often used on plastic to make it shiny (think Armorall type products). Really hard to get off. From there, plastic typically has a really low reactivity, so you need to figure out what sort of plastic you're dealing with, and find a primer that will work with it. It's possible, depending on the primer you find you need and the paint you're using that you need another primer to bridge chemically. Some paints don't work with some primers, so you might find you need a primer that works with the plastic primer AND the paint if the plastic primer won't play nice. It's not common, but it happens, and we don't know what you're working with. If you look around on the blind side of the part, you may be able to find debossed stamping telling you what you're working with.

 

[jeepin48]

I would start with Acetone wash/rub and then a plastic primer and then what ever paint you got.

 

[93civej1]

Scuffing may or may not be necessary and may even be counterproductive. Prep and primer will be your most important factors. Make sure there is zero silicone (huge on plastic parts) or grease. The silicone will cause fisheyes, and it's often used on plastic to make it shiny (think Armorall type products). Really hard to get off. From there, plastic typically has a really low reactivity, so you need to figure out what sort of plastic you're dealing with, and find a primer that will work with it. It's possible, depending on the primer you find you need and the paint you're using that you need another primer to bridge chemically. Some paints don't work with some primers, so you might find you need a primer that works with the plastic primer AND the paint if the plastic primer won't play nice. It's not common, but it happens, and we don't know what you're working with. If you look around on the blind side of the part, you may be able to find debossed stamping telling you what you're working with.

its the plastic trim pieces that go on the outside of the grille on rubicons and overlands. The come painted on them. If you order them from mopar they come unpainted black plastic.

 

[spectre6000]

What type of plastic does it say it is?

 

[Tackett1980]

What type of plastic does it say it is?

this is important information. Stuff like hdpe will not let anything stick to it at all no matter what you do to it.

 

[Chance575]

Scotch brite the part and you can also use some plastic adhesion promoter.

dont know if I’d use acetone with trying it on the back first, it may eat into the parts. I use a water/soy based degreaser cleaner.

 

[93civej1]

this is important information. Stuff like hdpe will not let anything stick to it at all no matter what you do to it.

Ill look in a moment on plastic type. Do you sand between coats or only certain coats, or only after final coat of clear?

 

[93civej1]

I went and looked at the parts, I did not see anything on them stating type of plastic. Only the mopar emblem, a 16,17,18,19,20,21 thing and the part number

 

[CJ5w4wdSmokyOnMyTail]

I painted a whole bunch of plastic interior and exterior parts on my Sarge Green Mojave. Started by watching a ton of YT vids about how to paint plastic.

I ended up using SEM products to clean the parts (I didn't sand most of the parts), then the SEM plastic adhesion promoter (2 coats). Then the spray paint (I did NOT use Mopar touch up paint because I read it actually is for "touching up" and NOT for painting whole parts - so it is manufactured to be kinda "runny" and too thin for actual paint jobs). I ordered the custom spray paint from a nearby automotive paint specialty shop.

After 3 coats of paint, I clear coated with 2-3 coats of enamel clear coat.

Buying the SEM products and the custom paint may be a bit pricy to paint one small part. But, after you do one part, you may likely want to do more. And having all the needed painting products on hand makes it easy.

Good luck! You'll do fine - and then do more!

 

[93civej1]

I painted a whole bunch of plastic interior and exterior parts on my Sarge Green Mojave. Started by watching a ton of YT vids about how to paint plastic.

I ended up using SEM products to clean the parts (I didn't sand most of the parts), then the SEM plastic adhesion promoter (2 coats). Then the spray paint (I did NOT use Mopar touch up paint because I read it actually is for "touching up" and NOT for painting whole parts - so it is manufactured to be kinda "runny" and too thin for actual paint jobs). I ordered the custom spray paint from a nearby automotive paint specialty shop.

After 3 coats of paint, I clear coated with 2-3 coats of enamel clear coat.

Buying the SEM products and the custom paint may be a bit pricy to paint one small part. But, after you do one part, you may likely want to do more. And having all the needed painting products on hand makes it easy.

Good luck! You'll do fine - and then do more!

Thanks. So you did not do any sanding at all? Not even a wet sand on certain coats or the final clear?

 

[MrFahrenheit]

Keep in mind that most primers sold at the big box stores are not for lacquer top coats. The mopar spray paints are lacquer and need compatible primer/clear coats.

lacquer paint over normal primer will shrivel up and not look good

 

[punk'n]

Clean with the proper cleaner like Prep-sol to remove wax, grease and silicone.
Abrade the plastic with scotch-brite pads (maroon colored is 320-400 grit).
Use an adhesion promoter like Bulldog by KleenStrip.
One or two light coats of prime followed by 2-3 light color coats.
Topcoat with clear for UV protection.

https://www.automotivetouchup.com/ carries most of the supplies including color matched paint by code. Their aerosol cans actually spray pretty nice for small projects. Much better than typical spray cans. They sell topcoat clear in acrylic lacquer. If you purchase from them, their various coats will all be compatible. They also sell SprayMax 2K clear as linked above in Amazon.

Note that SprayMAx 2K is a 2 part, very durable, high UV protectant that is also highly toxic unlike regular rattle can clear. The 2 parts are mixed in the can by puncturing an internal bag that contains the isocyanate catalyst. That catalyst is why you must wear a respirator when applying.

Proper prep will result in better end results.

Have fun and good luck!

Sponsored