Rust problems on sliders/bumper

So I don't know if I'm being more scared than I should be. Hopefully you can either relieve my fears, or let me know if I should fix.

#1
I have weld on sliders, and there's some rust in some places that I didn't get to with the rust-oleum. (In-between the bottom of the truck and top of the slider next to the weld joint. It sat for a year like that while I was deployed. It was in California. I sanded off what I could and coated it when I came back. I'm concerned about it spreading to my frame. Is that a valid concern?

#2
I have a steel front bumper that I rattle canned with Rust-Oleum as well. It looks like it's started to come off, friction from winds at freeway speeds maybe? Has anyone else experienced this, and do you think my guess is correct?

 

On the sliders/frame, clean up what you can with steel wool. Use acetone or isopropyl alcohol to degrease the area. If there is still rust, go at it with rust reformer as a base coat and top coat it with some semi gloss black. I have weld ons too, and made sure everything was coated well given the frame issues. On the inside of the frame, there was a couple holes from the factory that were opposite of the slider mounts. I sealed those up with 3m seam sealer to ensure water cant get between the frame/mount through that hole. Also made sure the inside frame sections got coated well (eastwood internal frame costing and rustoleum semi gloss black). When I do my painting and touch ups on the sliders, I cover my truck with butcher paper to avoid overspray.

The bumper issue may come down to how well it was prepped before coating. Myself, I used rustoleum bed liner for my bumper and it came out great. No issues after a few months (installed this summer) and its easy to touch up. Prepping is key to any painting job.

 

Thanks, I have already sanded down the rust and coated the slider spots with Rust-Oleum. You think I'll need to strip it off and do the method you recommend?

I'll definitely look for those holes you mention and see if I can plug them up...

How often do you touch them up? Just curious.

 

I think you should be good if its already coated, just keep an eye on it for any further rust or chipping.

I live in new england where they use all sorts of corrosive crap to keep snow off the roads so I usually check my frame for rust/paint chipping at least once a year; touching up as needed. My sliders went on last summer and Ive touched them up twice. They get used, so i try to get them coated before winter and salt hit the roads.

 

Try these products from Rustoleum to treat all visible rust. I prefer not to use aerosol cans since they are heavily thinned, better to use a compressor with an hvlp gun. Even a cheap Hvlp spray gun will give better results than spray cans Ime.

Pressure wash the underchassis first. I would also take a clean wire brush to knock off any loose paint, chip off or disc sand welding slag etc. And scuff existing paint with a scuff pad.

Treat all rust with Rustoleum Rust Dissolver gel. Follow the instructions on the bottle:

https://www.rustoleum.com/product-c...s/auto/removers-and-chemicals/rust-dissolver/

Then follow up with the Rustoleum primer:

$17 Rust-Oleum 7769502 Protective Enamel Paint Stops Rust, 1 Quarts (Pack of 1), Flat Rusty Metal Primer

https://www.amazon.com/Rust-Oleum-7...ywords=Primer+rustoleum&qid=1602700090&sr=8-6

After the primer flashes off, apply/spray Rustoleum semi gloss black:

$27 Rust-Oleum 7798502 Stops Rust Brush On Paint, Quart, Semi-Gloss Black, 1 Quarts (Pack of 1)

https://www.amazon.com/Rust-Oleum-7...2701646&sprefix=+rustoleum+semi+gloss+&sr=8-2

Rustoleum also offers a solvent to thin their paints, I usually use just enough to make it spray thru the HVLP gun:

https://www.rustoleum.com/product-c...voc-professional-grade-multi-purpose-solvent/

Plenty of HVLP spray guns will work for spraying the underchassis. Just buy a decent one.

 

Glad I got my 100% duty cycle vair a few days ago . I don't have a pressure washer though. These are good instructions. I'll see if I can get out there tomorrow and give it a go.

 

Car painter here. Imo use raptor spray on bedliner works great. Also if you get chips in it. Touches up well. 2 part ureathane coating very durable and doesn’t chalk out from UV’s. Also don’t use Rustoleum. Get a nice urethane 2 part coating. That other stuff won’t hold up as stated above. To get a good repair sand and prep really well. Any of that coating coming off definitely sand it off prior to refinishing.

 

Nice post. Former fleet and heavy equipment painter here. Used to paint lots of now banned 2 part urethanes and 2 part epoxies on frames and underchassis of heavy equipment used in extreme environments. To really take care of already rusted equipment it should be degreased, sandblasted and then repainted with industrial grade undercoats and topcoat. The industrial market has dozens if not hundreds of products out there.

For the average diy'er the Rustoleum enamel paints in a quart or gallon can work extremely well if the prep work is good for a non catalyst paint and are very easy for the average diy'er. Later touch-up is easy too. I know because I've used it for many years on various equipment.

These new Tacomas come with bare metal on alot of their underchassis components and if prepared/coated early on, Rustoleum enamels from an HVLP gun will hold up (not their aerosol spray can variety, it's too thinned out). Key is letting this paint cure before heavy service since it's oil and solvent based.

There are other industrial products out there that work extremely well but are very expensive and require some experience to learn to apply for the average diy'er. Preparation is everything. Most of the industrial coatings I used to spray are either banned or have been reformulated to meet EPA emissions. And required a NIOSH approved air supplied full hood respirator.

If I were to use a urethane I would take a hard look at Sherwin Williams Polane T (polyurethane). I can say from experience the old version holds up well, is very durable and easy to spray. I'm not a fan of undercoatings except in the wheel wells where chips occur, IMO most underchassis look like $hit when sprayed with bedliner or undercoating.

 

I don't think I'm going to do a full on undercoating I'm honestly not sure if there's stuff down there I need to avoid, and if so what that'd be. Exhaust pipe? Tranny? Etc. I've just spot checked with the rust oleum rattle can from time to time.

And sounds like I'll need to get a sand blaster then as well. That will work well for my front bumper, but since the sliders are weld on, I can't take them off (kicking myself right now for not going bolt on). The area where the rust is, is a very tight little spot. I could barely get to it with the rattle can. In fact I was spraying blind and over spraying to so make sure I got it. The only way I found the rust was by feel. It's on the top of the beam that is welded to the frame. And there's very little clearance between the top of that beam and the underside of the truck itself.

I'm not sure if a gun is going to be able to reach up in there. I could theoretically hand sand it and use the same primer and paints you recommended with a brush though right? You have any thoughts on naval jelly?

 

Those spots on the frame by your sliders if not visible maybe get some por15 satin black prep area and touch up with that just a thought.

 

The wind causing paint to chip and rust. That's a new one.

 

I mean I don't know what else would make paint disappear lol. And start to rust once the metal gets exposed to air.

 

I'd guess a shit prep job....

 

I'm not a painter, and didn't even know how to do a proper prep until these guys just offered their advice. Which is more than you've done. But thanks for point that out.

 

Pay no attention OP. Do the touch up underside by your sliders no problem. Never seen under there. Also for the bumper. Plan time before it’s gets real bad. Remove bumper and prep it perfect. Bare metal then epoxy primer than a nice 2 part urethane. Will hold up for a long time.

 

For light rust the Rustoleum gel I provided a link to works well. It dissolves the rust and provides a mild anti rust coating. Read the reviews for it.

For sandblasting to work you need to degrease it first. We would degrease a frame by using a steam cleaner pressure washer with agents added to the hot tank. You had to be careful where you pointed the hot wand and sometimes wear a rain suit.

You also have to be careful sandblasting and only blast the rusted areas to be painted. This means more prep work. Afterwards the excess sand leftover had to be blown out with a filtered air blower. The primer had to be applied fairly quickly and never in humid conditions, otherwise rust begins almost immediately. We ran 2 shifts and never sandblasted unless we were ready to paint soon after.

We had one semi tractor that the company like to use for truck shows mostly in Las Vegas. The driver like to wax the paint and polish all the rims and add ons. They would enter the truck (76 Peterbilt cabover) in the working class competition and it almost always took first class for a number of years. Of course we always gave the chassis a fresh coat of Dupont Imron (99U black) with a couple coats of Imron clear. The truck trophies were kept upstairs and shown off at staff parties. Lols

 

Once you start wheeling your truck, your bumper, sliders, and frame will get plenty of scars anyway. Just plan for yearly touch-up at the end of each wheeling season. Clean the rusted areas with some alcohol, then rattlecan with some Tremclad semigloss rust paint (it blends well with existing paint and powder coat). It will be a continuous yearly process with no end (the rocks on the trail don't care about your prep work), so I wouldn't bother with removing the bumper.

 

Wow, sounds like a lot of work. I don't have a pressure washer to do all that, but I could get some degreaser and apply by hand I suppose?

I am installing a winch and will have to take the bumper off soon anyhow, and unfortunately there's not too many trails around me now from what I hear (just moved) so it might end up being mostly a pavement princess for a few years until I transfer again. In which case, imma baby the crap out of it .

 

Winch on a pavement princess