Painting plastic pieces.

[badmpnodonut]

I bought an aftermarket hood that has the cowl induction and has a billet insert on the front. My question is: the part where the billet is located is plastic, and is going to be painted the same color as the hood. I was going to spray it first with the Bulldog plastic adhesion promoter. Do I need to spray sealer on it after I spray the promoter? I am going to attached it to the hood before I paint it because it needs to be glued on and I don't want to run the risk of getting any glue on the fresh paint by mistake. So spraying it with sealer may not be avoidable since I am going to seal the hood anyway. And another question: will it hurt the primer on the hood if I get the promoter on it?


Sorry for the repeat of the question... I meant to put it under the General Discussions forum.

[Roch_Greg]

I've been working on some plastic parts these last few weeks and can share what I've found.

You will only need the adhesion promoter if the part is raw plastic (un-primered).

If it is raw plastic, scuff it up (use a scotch brite pad or P600 paper) then apply the adhesion promoter (according to directions), let it flash and lay your primer down. Most adhesion promoters have a "window" of time that the primer/paint needs to be applied.

*** warning *** use only cleaners made to used with plastics some solvents can cause a reaction.

If the part is already primered, again scuff as before and just lay the primer down. Avoid cutting/sanding through the primer.

In both cases I would check your products (primer if needed, topcoat and clear and see if they require any special additives when being used on plastic.

I don't see the need for a Sealer (unless you mean a primer/sealer)

I have experienced and read that some promoters will cause primer or paint to lift. Unfortunately the only way to find out was to "test in a inconspicous spot" (I love it when they say that).

Does the "glue" your using say it needs to be bonded to bare or painted metal? If I can help it, removable/replaceable parts are always painted off the car/panel. You can always mask off the area around where you planning to mount the part to keep that clean.

Hopefully Len will chime in, I've read over the years here a few posts where he's done something like this (IIRC)