Painting Plastic

[BPT]

I've talked to an auto body/painter I know and he told me there's nothing you can't paint, it just depends on how much time, effort, and, of course, money you want to spend on it.

I have a plastic case I want to paint, similar to a Pelican but possibly a slightly different type of plastic.  The paint guy told me how to do it using etching and 2 part primers, which paint, etc.  It's doable but will be a little expensive and will take some time, especially due to my lack of experience.

Has anyone here had any luck painting hard to paint plastics using simpler methods or cheaper paints?  Of course I want them to look decent but I think the biggest difficulty is getting the paint to stick and last a while.

I'll do it the more complex way if necessary but figured I'd check here to see if anybody had discovered a shortcut to this.  The material is referred to as a special "polymer resin".

      Thanks in advance.

[marcmax]

I have painted plastic panniers and a fiber glass sidecar body with good results. Etching primer is a must to get a good base to adhere to. Krylon makes a line of rattle can paint specifically for plastic products that works well/ I have several items going on 4-5 years that still look good.

[BPT]

Do you remember what etching primer you used and does the type of plastic matter?  The guy I talked to recommended an adhesion promoter, a 2 part epoxy primer, and then painting (and he was specific with that, maybe some type of urethane?). 

I know of Krylon Fusion paint. I've used it on some less-likely-to-be-abused things.  I've read mixed reviews on it with plastic cases.  But some have said it worked great. 

I think fiberglass is OK to paint but what are the panniers made out of?  Just a guess, but I'm thinking they might be more difficult?  I'm considering doing a test run on one if mine with the rattle can recommendations.

[BPT]

And I guess I should ask you how the sidecar painting went, Marcmax.  I am wanting to change the color of my bike but at the moment can't afford to have done by somebody.  I've been considering doing it myself but I'm short of confidence in my skills. 

[marcmax]

I am not a painter so my methods are just seat of the pants trials. The sidecar was done entirely with rattle cans from the local auto parts store. For primer I just looked for one that said it was an etching primer on the can and the right color (yes it comes in different colors). I was going from a dark maroon to all white so I used a light grey primer. Sanded the entire thing and sprayed a primer coat. When it dried I wet sanded it and added another coat. Wet sanded again and another coat. Then I did the same with the color coat the same way, three coats of white. After the last white coat I wet sanded again and added a clear coat. All in all it took a little over a week of paint, dry, sand and repeat. Is it perfect? Someone who paints for a living could find every flaw but from three feet away I think it looks great.

[wilcom]

For plastic and upholstery I use SEM, a product sold at automotive paint stores. Spray it on and go ride. I painted a brown 1979 R65 seat black.... 10 years later it was still black and still looked like new.

[BPT]

Wow Marcmax, the whole thing with cans?  My trigger finger cramps up thinking about it.  I figured that if I was going to attempt the sidecar, I'd probably get a cheap gun.  Both the auto body guy and our own Justin here have said they'd had good luck with cheap ones from Harbor Freight.  But nice to know you were able to get decent results from a can, I'll have to keep that in mind.  For the primer, it's the cases I'm concerned about since they're notorious for being difficult.  I guess that I'll just have to do a test spray.

Thanks Wilcom, I'd forgotten about SEM.  That came up when I was looking for a way to color a faded cover I have.  I know that they make tons of stuff and are known for sticking to things that aren't easy to deal with.  I'll have to look at their line again and see what they have for slick plastics.
Thank you, gentlemen!

[Justin B.]

Go to eastwoodco.com, they'll have everything you need.  For plastic you should use an "adhesion promoter" and I know Eastwood has a "plastic restorer" spray paint.

[BPT]

Hey Justin, you've hit on what I've been told is the most important part, the adhesion promoter. Do you have any personal experience with these?

What I'm wondering is are you more free to choose paint if you're using the adhesion promoter or is it still necessary to use the stuff for trickier applications?  And how about primer?  One guy told me to use self-etching primer. A guy from SEM said that it was only necessary if you needed to cover up imperfections.  But if you're OK with how your surface looks, you can paint after the adhesion promoter.

I'll most likely need some kind of primer for scratches and knicks but it'd be nice to know if it is possible to leave it out if your surface is good.

[Justin B.]

Adhesion promoter, primer surfacer to fill in imperfections, then color.  Not sure why an etch primer would be used as they are usually for bare metal...

[qwerty123]

A small detail, but in case of a lot of rattle can use you can use these things to help prevent trigger-finger fatigue. They work okay.

[BPT]

I'd wonder if those were any good.  If I go the rattle can route, I'll keep those in mind, thanks.