Aftermarket bumper rust

BroncoHooves

Tremor Development
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Got this one problem spot (and only one on the entire bumper) on the inside of my Steelcraft bumper that I've tried to remedy many times, but it keeps showing up within a day or two on the exterior of the bumper. It's not originating from the exterior. It will drip down to the corner, and as you drive, it will splash back on the exterior of it, making it look unsightly.

I used an endoscope camera, and confirmed that it's coming from the tangent, or even beyond past the tangent, unaccessible, of the top of the pipe and the flat plate on top, so it is hard to really address the area properly with mechanical means without cutting the pieces completely apart. Liberally applied chlorinated brake cleaner and a nylon brush is the extent of any cleaning done.

Contacting the warranty dept. tomorrow, but wanted to see if some 2K epoxy primer from Eastwood would work better than the below stuff I've tried, if anyone here has used it?

Products I've tried so far that have not worked:

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I have similar issues with my fab 4 bumper. Rust-oleum has NOT worked for me either. I was thinking a decent rust converter and some epoxy paint. As long as the rust is neutralized I am not going to worry about having it smooth. On the underside of course it doesn't matter.

I have some N Fab running boards that need it badly too.
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I have similar issues with my fab 4 bumper. Rust-oleum has NOT worked for me either. I was thinking a decent rust converter and some epoxy paint. As long as the rust is neutralized I am not going to worry about having it smooth. On the underside of course it doesn't matter.

I have some N Fab running boards that need it badly too.
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Glad I'm not the only one at least. Did you look into 2K based epoxies? There's a button on bottom of can you have to hit to release the catalyst. Supposed to be next best thing to a real spray gun.

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I just saw that. Reviews seem to be good. This is a primer and would need a topcoat also. The spray is key to get into some of those areas you show that a brush won't reach. I think I am going to try it. I have to wait until the weather warms up since my shop isn't heated or insulated.
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Or you could just try this :)
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If the bumper was removed would pouring a product in the area work better than spraying it? Just in the hard ro get to area of course.
 
If the bumper was removed would pouring a product in the area work better than spraying it? Just in the hard ro get to area of course.
I'm not sure. The viscosity may prevent it from going where I truly need it to be, which I think is beyond what is even visible with the endoscope camera.
 
If the thicker epoxy covers the gaps and blocks off the moisture then the rust shouldn’t come back. It’s like mold, if you cut off the moisture it can’t grow. Maybe some rust gets trapped but it shouldn’t propagate. Otherwise maybe the line x is better but you have to like the look.
 
I'm not sure. The viscosity may prevent it from going where I truly need it to be, which I think is beyond what is even visible with the endoscope camera.

I guess it would depend on the product. I know spray will often not go beyond what's visible, not "creep" or seep into areas that a thin poured, or even brushed on liquid can. I don't know how thin the rust converters or neutralizers are that come in a bottle.
 
I use this on all my projects, it’s a bit pricey.

 
I use this on all my projects, it’s a bit pricey.

Looks like it needs to be fully submerged according to the website. Not something I can do with the bumper.
 
I just use a spray bottle that’s rated for chemicals. But protect your concrete if you are in a shop setting.
 
Glad I'm not the only one at least. Did you look into 2K based epoxies? There's a button on bottom of can you have to hit to release the catalyst. Supposed to be next best thing to a real spray gun.

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I've used the 2K on my old f250 and it lasts longer than most coatings but eventually bled through in "spots". It took 2-3 years, but it will eventually fail if the metal wasn't completely covered by a good iron oxide primer.

The key is obviously a good primer application prior to paint. Paint after the fact, (covering rust) may work for a while, but you can't guarantee a complete seal. It's better than nothing but may have to be redone in time.

Another coating is (as mentioned) POR 15, or Eastwood encapsulator.
 
I've used the 2K on my old f250 and it lasts longer than most coatings but eventually bled through in "spots". It took 2-3 years, but it will eventually fail if the metal wasn't completely covered by a good iron oxide primer.

The key is obviously a good primer application prior to paint. Paint after the fact, (covering rust) may work for a while, but you can't guarantee a complete seal. It's better than nothing but may have to be redone in time.

Another coating is (as mentioned) POR 15, or Eastwood encapsulator.
So the encapsulator looks like it doesn’t require any topcoat. It doesn’t say anything against putting a coat of epoxy over top. I would think that would be pretty durable for things like my nerf bars that a glossy finish would look better and gets lots of road rash. Shouldn’t get any spotting if the encapsulator works.

If it really does neutralize rust then the epoxy paint topcoat could be the best DIY option. powder coating is more durable than the epoxy but not so DIY friendly obviously.

I’m going to try it and see how it goes
 
So the encapsulator looks like it doesn’t require any topcoat. It doesn’t say anything against putting a coat of epoxy over top. I would think that would be pretty durable for things like my nerf bars that a glossy finish would look better and gets lots of road rash. Shouldn’t get any spotting if the encapsulator works.

If it really does neutralize rust then the epoxy paint topcoat could be the best DIY option. powder coating is more durable than the epoxy but not so DIY friendly obviously.

I’m going to try it and see how it goes
Are you trying the POR-15 or the Eastwood encapsulator?
 
I thought POR-15 had a product you could just apply directly to the rust and it would neutralize and prevent further spread.
 
I’m going to try the encapsulator with epoxy over it That’s if it ever warms up here!

I may have to sand the old paint that is not rusted before the encapsulator but we’ll have to see
 
I’m going to try the encapsulator with epoxy over it That’s if it ever warms up here!

I may have to sand the old paint that is not rusted before the encapsulator but we’ll have to see
Which brand? POR-15 encapsulator, or Eastwood's?
 
POR-15 does not need a top coat unless the area is exposed to UV. It will chalk out and be less aesthetically pleasing but the protection and durability will remain.

It is also a good idea to knock off any large chunks of rust but mild rust can be coated straight over.

Another idea if you have not yet done this repair would be to coat the rusted area with POR and then use a cavity wax with a wand to cover the inside parts that are not visible.
 
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