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honda88mike
11-20-2002, 08:40 AM
:help: I'm about to paint my stock (unpainted) bumpers to match the Polar White pain on the rest of my car. I heard someone say something about a paint adhesive that needed to be sprayed first, does anyone know if I need that or a product name? Anyone done this before?

staticpat
11-20-2002, 08:42 AM
you'll need some type of flex agent.

pmip
11-20-2002, 10:10 AM
I will be repainting my car over thanksgiving break, and after talking to many body shops, they recommended an adhesion promotor sprayed on the bumpers, then a flex agent mixed in with the paint. I tried looking all over for the flex agent and adhesion promotor, and the only place I could find that had them was body shop supply places. Whether you actually need them, I don't know. I've heard about people on this board who just painted them without adding anything, but it chipped off fast.

pearldrop
11-20-2002, 10:19 AM
Neither of those is necessary. The only thing that you need to do is make sure that the plastic is exceptionally clean with a professional degreaser and then scuff it lightly with a scotch brite pad. If you have ever sprayed it with armor all it can cause problems so you need to clean it ten times as much as you think you need to. Paint will stick to plastic just fine without an adhesion promoter, no promoter is ever used from the factory to spray the rest of the bumper so it isn't necessary on the strips either. There is no more flex in the bumper than in the sheet metal so a flex agent isn't necessary and will actually increase the chance of peeling paint. Of course I don't go around hitting stuff with my cars but I had mine painted like this for 7 years and never had a single crack or flake off of my moldings or bumpers.

pmip
11-20-2002, 10:37 AM
Hey pearldrop - I thought I remembered you saying something about buying a new rear bumper and moldings, so that the paint would stick better. Anyways, I have probably 10 years of armorall on the bumpers and moldings, and there is no way I could possibly clean it all off, and so I think an adhesion promotor is a good thing. As for the flex agent, it will make your paint more flexable (so if people hit you in the parking lot, it's less likely to crack), but it will also make your paint fade faster, so it's up to you.

offthahook
11-20-2002, 03:31 PM
Pearldrop is normally right on, but I must disagree. I had my rub strips painted white along with the rest of the bumper. The bumper cover was NEW. Dude scuffed it up, but didn't use the flex agent or adhesive promoter, It peeled at the rub strips in a short time. Not really bad, but it wasn't getting any better going thru the car wash and rain. Plus, I had to get a new bumper cover cuz stripping the old paint was too $$$ and hard. If you're going to do it right, you should use both products, IMO. You are really rolling the dice if you try to cut corners in this case. Think about spray painting a metal piece and a plastic piece. You know which one holds up better over time.

BTW-- this was just the front bumper that failed. The rear one is fine so far.

pearldrop
11-20-2002, 04:08 PM
The problem must have been a low quality paint or the paint ended up brittle. Did you use a genuine Honda bumper? The replacement bumpers are terrible quality and paint does not like to stick to them.
From the factory, there is no flex agent or adhesion promoter.
I got rear ended and the license plate bolts of the car behind me left indents in the strip on the rear bumper. The paint did not come off or even crack.
I had a rolled up barbed wire fence fall off of a truck in front of me on the freeway and I hit it. It left some scratches in the bumper and dented the fender but it never chipped. I backed off of a 2x4 one time and it flipped up and folded the bottom corner of the bumper under the car. It left some crease marks but never chipped or flaked off, and it was folded completely under to where I couldn't see it anymore.

pearldrop
11-21-2002, 08:01 AM
Actually, last night I was thinking about it. There could be a difference between 86-87 bumpers and 88-89 bumpers. I know that the whole bumper on 87's is the exact same. The molding is not raised and it is the same texture as the rest of the bumper, which is smooth.
I've never seen an unpainted 89 bumper so the raised part may actually be different than the smooth part of the bumper. If it is textured, then it may cause the paint to not stick as well and an adhesion promoter may be necessary. I still stick by the fact that a flex agent isn't necessary.

DBMaster
11-21-2002, 08:06 AM
I bought the adhesion promoter I used at Auto Zone in a spray can. You should not have too much trouble with the bumpers. I used sandpaper and acetone to clean the plastic.

The side moldings are another story. They are coated with a softer rubber and even after snading and chemical cleaning I still had some beading of the adhesion promoter due to residue or silicone, Back to Black, etc. in the rubber.

I have had to repaint my fonrt rub strip three times to get the paint to stay on without flaking off in large areas. I have had better luck with the back bumper strip. The acetone was somethng I started using after my first attempts. It seems to clean out the oily crap better.

offthahook
11-21-2002, 08:43 AM
Originally posted by pearldrop
Actually, last night I was thinking about it. There could be a difference between 86-87 bumpers and 88-89 bumpers. I know that the whole bumper on 87's is the exact same. The molding is not raised and it is the same texture as the rest of the bumper, which is smooth.
I've never seen an unpainted 89 bumper so the raised part may actually be different than the smooth part of the bumper. If it is textured, then it may cause the paint to not stick as well and an adhesion promoter may be necessary. I still stick by the fact that a flex agent isn't necessary.

I think when you buy the cover, you specify DX or LX/LX-i. The rubstrips are textured; the rest is smooth (ready for paint). I think painting a DX bumper might be hard cuz the whole thing might be beaded/textured. In any case, mine is AM ($105) and it lookd really good in that Taffetta White. I think the back one will be fine since it doesn't take the elements like the front one does.

honda88mike
11-25-2002, 10:32 AM
Does anyone have a Brand name that I could look for, for the adhesion promoter?

pmip
11-25-2002, 12:50 PM
Originally posted by honda88mike
Does anyone have a Brand name that I could look for, for the adhesion promoter?

I'm using Mar-Hyde.

DBMaster
11-25-2002, 07:17 PM
The stuff I bought at Auto Zone is called "Bond Aid." It is made by Kleen Strip.

The can was about 6 or 8 bucks. It goes a long way.

flamed89
11-25-2002, 08:14 PM
i'm gonna have to go with pearl on this one! i painted my mouldings on my car and my g/f hit the corner of the bumper with her car and the paint just cracked. no adhesion promoter,no flex agent! all i did was scuff the bumpers down with a scotch brite pad and wash it with a solvelt cleaner. and i work in a body shop and no body shop i have worked in has ever used a flex agent.