Can someone give me a rundown of everything I need to do to prep and primer my lower valence for the paint shop? It's a new Edge valence from LMC that is RTP so its already clean and ready to be sanded/primered/wetsanded. But I need specifics on grit and all that stuff because I've never done this before. And any recommendation for which brand rattlecan primer to use would be cool. Thanks

 

Is it already primed? if its a RTP bumper then you shouldnt need to reprime it. Check and make sure.

If its primed already, just get a grey scotchbrite pad and some water and soap. scuff it good, dont break through the primer, and hose it off really really well. Dry it with some paper towels (no cloth towels that were in the dryer.... the softener on them will cause fisheyes) and then you are ready as soon as the water is dry. Dont let water dry on the surface and leave spots. the calcium deposits will show up if you dont take them off.

 

My bad, I didn't mean RTP then. I meant to say it's an unprepped finish. Or RTP as in 'ready to prep' lol

 

ok then. if its raw plastic and all you have is rattle can access then id do it this way.

1 - Wash the bumper and scuff it with soap, warm water and a grey scotchbrite pad.

2 - Dry it and repeat the process

3 - Dry it again and use some aerosol adhesion promotor. Klean Strip makes one under the Bulldog brand name. it works well and its cheap enough. Directions are on the back of the can, but basically spray two LIGHT/MEDIUM coats on the plastic and allow it to flash 15 minutes after each coat. Now, they say you can paint directly over it. Ive never been a fan of doing that, especially on something like a bumper that is gonna take a TON of rocks and gravel to it over time. So id prime it with ....

4 - An aerosol primer from Transtar or SEM makes that is meant for flexible parts. However, they are a ***** to sand. They are one of the few that come in an aerosol though. Put on 2 or three MEDIUM coats. Its a new part, you dont need to hammer it on there. Let it flash (dry) between each coat about 10 or 15 minutes or you will either run it or get pinholes.

5 - wait a day then sand the primer with some 600 grit wet sandpaper, and some warm water. The warm water is only to keep you from freezing your nuts off. Its been cold lately. All you want to do is remove the texture in the primer. Once the texture is out, stop sanding. You dont want to break through it. Chances are you will break through in some corners, but try to keep it to a minimum.

If you were in SoCal i could just paint it for you, but well, you arent lol. I personally dont use rattle can products, but i understand the situation you are in so thats what id do, thats what ive done in the past, and it works well enough. The flexible primer is gonna suck to sand though.

 

Great info, thanks. So I don't have to sand the plastic before laying down the adhesion promoter?

Also, I'm assuming that paintable valances from LMCtruck.com don't come primed. (If they did that would be AWESOME)

 

OOPS sorry for the late reply. Yes you will need to scuff it before using the adhesion promotor. The grey scotchbrite is usually enough though. You just want a scuffing on there, if you prefer to sand, the 600 or 800 grit paper is enough but be forwarned that the plastic will have a tendency to leave little hairs that stick up. They gotta be sanded smooth first but its just more work than you really need to do.