Edionne13

I've been shooting around the idea of using por-15 on my TG front bumper. I've painted it I believe 4 times due to I tehe reason have used 3 coats of primer then 4 coats of rusterolm engine paint. 2 clear coats and within matter of months chips off. I don't know whether to buy a ping or quart or buy spray cans. There's so many types on the site. Not sure what to choose.

Swimmerboy2112

iTrader: (2)

While I use POR-15 and advocate its use on frames, I would suggest against using it on the bumper for the fact that it will fade fairly quickly. Now if you wanted to put it on first then paint over it, that would work.

Gizler00

iTrader: (1)

Are you prepping the bumper really well before you are spraying on the paint? If it is cleaned and prepped well, it should hold up for a long time. Obviously not to scratches or bumps. You could also put some bed liner on it. Might look cool and hold up good.

Edionne13

The bumper is down to bare metal every time. I'll probably put it on first then paint over it

slacker

iTrader: (1)

I had some left over POR when I did my frame , an decided to "test" it on my rear bumper ..

I didn't even clean the dirt off !! just slapped the POR over all the crap that was on there , including the rust .. (I have pics somewhere )
that was 6 YEARS ago .. I just did it again because the rust just started to poke threw again .

POR dosnt like UV rays , and will "chalk" ... wasn't to bad for a bumper IMO .. I'm absolutely sold on this product , it has surprised me time after time


.

94 SR5 Mountaineer

While POR15 is arguably the best for rust prevention, I think your problem would be solved with taking it down to bare metal, using a good oil base primer (rustoleum etc) and oil base topcoat (rustoleum etc). No clearcoat needed and you can get any look you want: hammered, flat, gloss, whatever.

As long as you take the time to degrease and scuff the surface of the metal, it won't chip off on its own.

Mike_Honcho

I agree with Mountaineer and Gizler. It's a prep problem.

If paint is sloughing off, it hasn't adhered to the surface well because of inadequate surface prep, an unclean surface, or applying the paint/primer outside of the recommended temp & humidity range.

Painting is hard and it really is a sanding and cleaning project in disguise. If you are painting the metal, it needs to be roughed up or "keyed" (not completely smooth) and using the right primer for the surface is important too.

If you have access to a sand blaster that is the best option. If not a wire brush on a drill or die grinder will work pretty good. Hand sanding can work too, but that is pretty labor intensive. I've heard that you can POR over rust (they say you need to treat it with their converter prep), but it's better to just do it once and not have to do it again and removing all rust just makes sense...

After that you need to use a prep product. I used to be skeptical about these but a good quality prep spray followed by a wipe down with a lint free cloth is huge! It is amazing the stuff that comes off even after you think it is clean. Skin oils from your hands, real oil, grease, road grime, wax... all that stuff is bad news for paint. I have been really happy with the Klean-Strip brand Prep-All spray. It comes in a green and red spray can with a black cap, and is available at Advanced Auto and those kind of places. There are other brands, I am just familiar with that one.

There are self etching primers available (duplicolor and rustoleum make them) if you think that is necessary and the base metal is the right material. Make sure to apply all spray paints in the appropriate temp, humidity and open/closed time period listed on the can. Each product is different even within the same brand.

Slacker and Swimmerboy are right. POR-15 isn't UV stable. If it is going to be exposed to light it needs to be topcoated with a compatible paint.

A better option is finding a product that they call "stone chip paint" in the UK. It is specifically designed for this and it is made for this application. I haven't been able to find it here in the States.

What is available on amazon and in some stores is paintable undercoating. Not all undercoatings are the same and they aren't the same as bed liner. I did all my skid plates in 3M's Paintable Undercoating 08882. The spray can is some color between red and purple and costs about $19. They make tons of other undercoatings that are cheaper, but they also won't last as long, and some don't ever set. This stuff won't get tacky in the summer and is paintable to match whatever color you desire.

Another very viable option when you weigh out the cost is powdercoating. If you can sand blast it and bring it to a powder coating place it will be pretty reasonable. Most of the cost is in the prep. Powder coating is way more durable then paint and it will still have the smooth glossy appearance of paint. Some of the local powder coating places here in Western NY offer lifetime warranties... By the time you prep, prime, and paint or POR then paint over top, powder coating becomes reasonable in price, especially if you have already done this multiple times before.

Hope this helps!! I actually need to do something with my lower bumper this summer because it is getting pretty pitted. Not sure which option I will choose... Let me know what you choose and how it turns out!