Plastic primer

[peteastra]

Hi

I have this primer i bought awhile ago. OCTORAL PA65

Was wondering how its used, its like a very thin solvent type.

[peteastra]

Or whats a good way to paint GTE bumper strips? ive tryed with Halfords plastic primer, but it seems i can always pick it back off with my fingernail.

[BigbaRd]

i think their all different, i ordered upol plastic primer which I ain't used yet. Not too sure if that's meant to be mixed either doesn't look like it does, just looks like a spirit!!

[peteastra]

it wouldnt be mixed with the paint, would it?

[BigbaRd]

nah, it eats into the bumper slightly (metlts it a lil bit for it to grip on and not peel) just i think with some of them you have a catalyst/hardener for it to work, ain't looked at mine propperly to see if their was a hardener.

[peteastra]

Cool, Thanks for that, makes sense.

I will look into if it needs a hardener.

[Cesaro]

The upol plastic primer I used couple of weeks back was straight out of the tin; ie no thinner. It was 1k celly tho so def no hardnener!

[LongLiveTheNova]

Plastic primer i have used from a spray can hasn't seemed to be much different than usual primer. I did my front bumpers with normal primer and the rear with plastic primer, i know i could easily scratch the paint off with my nail on either bumper( i scratched some of the paint off wiping mud off the bumper). Don't think they would take a pressure washer.
They ain't got any stone chips yet though.
Also i think the texture of the bumper caused it to take crap, cus i sprayed m3 mirrors and eyebrows and they came out shiny, and the paint took well, can't even mark it.

[alistairk]

textured plastic is always trickier than smooth plastic. thats why they sell the stuff that eats into the plastic to kinda etch it.

[Mike007]

If it looks like a solvent it is probably a plastic primer containing Chlorinated Poly-olefins which are particularly good for adhesion to Poly-propylene bumpers (which the majority of car bumpers tend to be). It doesn't 'eat in', but forms a chemical bond. The reason it looks like a solvent is because it is about 95-98% solvent. It means that the film thickness is only about 2microns.

The most important thing about plastic is to prep it properly. Personally I would clean it with a proper plastic cleaner using a scotch pad, wash it off with clean water, leave it to dry and then wipe it over with an anti-static wipe.

Mike

[Cesaro]

Yeh I find degreasing the surface really beneficial too.

[peteastra]

Right so it should acttually stick with this primer then (better had for £30 for 1L) do i spray it on or can i just brush it on?
Thanks for the advice.

[Mike007]

Spray it on if you can. The one advantage is that it's really easy to clean your gun afterwards!!!

Mike