As title states, I am having my front lip painted this following week. Its a polyurethane from ebay. I had gotten it painted previously and the painter did not do a good job prepping it as it was not primed, huge chunks of paint would peel off from little rock chips. I bought a new one, and now I want to prep it myself for the painter.

can anyone give me a good step by step way to prep the front lip? I plan to put primer on it and a few coats, and after its been painted/clearcoated I plan to spray paint defender by 3m "clear bra in a can".




Any info would happily appreciated

 

To be honest, polyurethane lips are horrible. Paint just doesn't stick to it to well, no matter how you prep it. It's eventually gonna look like crap, if you scrape or get chips. Depending on the type of paint you use, it may or may not chunk up. You're probably better off with waterbase paint cuz it's a lot more flexible than oil.

However, if you want you can still do it. Just make sure your prep is actually good, cuz it's a little bit more difficult than it seems.

- I would first wetsand the whole lip, with 400 grit sand paper. Make sure you get it good, cuz the coatings they use for polyurethane leaves a lot of silicone on the lip, and it will either fisheye or cause some kind of reaction.

- Then I would go over it with some kind of degreaser solution, we use Detro "Clean". Pretty much to remove all traces of silicone, wax, or other impurities on the surface. This is what we use.

- Next, use some adhesion promoter. Spray it as direction states.

- Then is the primer. Hopefully you can use an actual primer and not a spray can. If you can, use the ones that you have to mix and then shoot out of a spray gun. If you have to use the canned versions, make sure that you get a few good coats on.

- Now you have to wetsand the primer smooth and also touch up the pinholes and other imperfections.

Get a black spray can and just mist over the primer now. You don't have to shoot it spot on, but enough so that when you sand it you can see if there is primer still there. Wet sand it again with either 400 grit sandpaper (for oil based paint) or 600 grit (for water base). I would just use the 600 however cuz the there's less chances of the sandpaper lines showing up later, regardless of oil or water. You know you're done sanding when the surface is smooth, and you don't see anymore of the black spray paint. You might have a few random spots here and there no matter how much you sand, but that's fine.

- Now you have to touch up areas, whether it be pinholes, deep scratches, or even rough edges. Use spot putty or putty bondo and touch up those areas. After it dries, sand again till the area is filled and smoothened. If the areas you touched up were big, you can primer it again and then wet sand it.

You're pretty much done with prepping. After that it's up to the painter and paint materials! Good luck.

EDIT: Remember to have your paint shop shoot more adhesion promoter before the first basecoat, or it will have a higher chance of flaking off!