Self etching primer prep

JPHikr said:
Here is what I have used for many years.

https://www.ospho.com/
It works.

https://nationalsupplydirect.com/ospho-rust-treatment-gallon.html?ff=1&fp=4251
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That's my next purchase. Was going to suggest Ospho for prep but haven't used it myself, yet. Fantastic reviews and outcomes, from what Ive seen online.

EDIT: upon further online searching, it turns out that Klean Strip (see link) is the equivalent to Ospho. Read some of the reviews and found a video that also indicates their similarities. Heading down to my local HD to pickup a bottle and do some test patches on my JKU's axles —

https://www.homedepot.com/p/Klean-S...Metal-Prep-Rust-Inhibitor-GKPA30220/100406369
 
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Irun said:
FWIW, this is an area I've acquired some expertise in over the years. Self etching primer should only be used on new or cleaned up metal. If you have rust, clean it up with a wire wheel kit and drill, or a 120 grit flap disc for heavy scale. I scuff up the frame with a 220 or higher sandpaper, clean it with lacquer thinner, spray rust reformer over any rust, then top coat it. Below are the products I use and results I get every time.

Also, as @someguysjeep said, you need to stay on top of this with an annual re-treat, and never use bedliner or other products like that. You're just asking for trouble later.

View attachment 273799

View attachment 273800View attachment 273801
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Which one of the products you listed are you using as your "top coat"?
 
fourpointzero said:
@Rustynj I too live in Jersey. Im sure you're aware of how municipalities layer their streets with chemicals. That stuff gets caught in crevices and inside our frames. If its not cleaned off and protected, you'll be doing a frame swap or body work in very little time. A garage is also a frame saver. But Im extreme, though. I dont drive my TJ in the winter.

You must be vigil with rust on a TJ. Regular cleaning, retouching and a fall coating of Fluid Film or CRC corrosion inhibitor on and inside your frame is imperative to keep rust at bay. I use the following three products: Fluid Film, WD-40 (for quick touch ups) and CRC corrosion inhibitor: https://www.amazon.com/dp/B0000AXYA0/?tag=wranglerorg-20 Search them on YouTube, and you'll see that users have had great success with FF (or other lanolin products) and CRC. Ive even coated lightly rusted metals with either FF or the CRC and have seen the rust suspended. Meaning it remains but doesn't continue to grow or spred.

My process:
When I spot any kind of corrosion starting to show on my frame, I hit it with a rust dissolver (Rustoleum brand) which is basically Phosphoric Acid in gel form. There's quit a few brands with that ingredient that work similarly or possibly better. I like the gel because it can be applied from all angles and it tends to "stick" or hold to locations where applied. Then I wipe it down and apply either FF or CRC. Painting anything, I don't do until the summer. Just because temperatures are ideal and when its not humid, you yield better results. The final step is always either FF or CRC.
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Good post
 
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Bkspear said:
Which one of the products you listed are you using as your "top coat"?
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Krylon Fusion I believe.
Krylon.jpg
 
HornedToad said:
I’ll add my two cents on paint prep to support what has been said. For bare metal paint prep I used solvents like lacquer thinner, mineral spirits, and acetone for years and always had subpar results and eventual peeling here and there. I started using detergents (mostly simple green and sometimes dishsoap) about two years ago and the primer sticks so much better it’s amazing. Just make sure and rinse it off with clean water and let it air dry.
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That's an interesting take. I use dish soap on stuff that will fit in the mudroom sink but acetone exclusively on big stuff that I can't take inside. I haven't noticed much of a difference so far but I haven't had anything more than about 5 years yet.
 
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JPHikr said:
Here is what I have used for many years.

https://www.ospho.com/
It works.

https://nationalsupplydirect.com/ospho-rust-treatment-gallon.html?ff=1&fp=4251
Click to expand...

Never heard of that
May have to look into it. Thx

I would use Rustoleum Professional oil based paint (not spray can) afterwards to cover it all AFTER proper mitigation. Plus like someone else said Fluid Film annually

I used Rustoleum pro in a gallon to do my floorpan before sound deadener applied. Would prefer a satin finish for undercarriage

Kt1SbXB.jpg
 
I've used ospho. It works. Brush it on, don't spray it unless you're in proper PPE. You don't want that stuff in your lungs, eyes, or on your skin. It also works really well in a small plastic tub to soak small parts like fasteners. You still want to remove large flakes and scale but it reacts with rust to produce iron phosphate, a hard, black surface that's resistant to further corrosion.
 
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I know the OP's original question is about the exterior of the undercarriage, but OP, what is the condition of inside of your frame? That's where most of your attention should be focused. If already rusty, you can slow down the corrosion with Fluid Film (or Eastwood frame coating), but you can't stop it. My wallet is a LOT lighter after going through an extensive frame repair because of internal rust.
 
so from what I understand, these are the steps everyone has suggested.

1) Remove grime and grease. Use dish soap, or a wax/degreaser. Don’t use lacquer thinner, as @Superjay5 explained.

2) hit rust spots with rust reformer or dissolver then hit with wire brush/sand paper

3) use an etch primer on newly exposed metal.

4) Apply top coat of paint, such as krylon fushion

Now here are the questions I have for this process.

1) Anyone have recommended brands for a wax/ degreaser?

2) @Irun do you use all of those products or just by brand rustoleum/ krylon?

3) if you use an etch primer is it necessary to have a top coat two in one paint and primer like the suggested krylon brand?

4) for inside the frame you etch it first then apply fluid film? Or is that redundant. I know Eastwood has a frame coat product

Eastwood Coat
 
Duner said:
so from what I understand, these are the steps everyone has suggested.

1) Remove grime and grease. Use dish soap, or a wax/degreaser. Don’t use lacquer thinner, as @Superjay5 explained.

2) hit rust spots with rust reformer or dissolver then hit with wire brush/sand paper

3) use an etch primer on newly exposed metal.

4) Apply top coat of paint, such as krylon fushion

Now here are the questions I have for this process.

1) Anyone have recommended brands for a wax/ degreaser?
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Close. First is use a detergent soap followed by a thorough rinse. If you are going to use an abrasive then step 2 is a degreasing prep solvent. The reason you do those things first is to prevent the abrasive from driving dirt, oils, and silicone into the paint and metal which causes problems later. Next is mechanically (the abrasive thing) removing loose and visible rust. That is followed by using a rust converter like phosphoric acid that converts any any remaining THIN WELL ADHERED rust (iron oxide) to inert black iron phosohate. Or you can use a dissolver like Evapo Rust instead. Then a final round of detergent and degreaser before applying the coating system. Unless of course you are using a coating product like POR15 that likes a little bit of rust then you follow their directions to the letter. Clear as mud, right?
 
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This what I have used for close to 30 years, many of those years in a commercial setting. Works good

03663228-BB2B-4184-9A7B-11ACF3B874E5.png
 
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steelhd said:
Close. First is use a detergent soap followed by a thorough rinse. If you are going to use an abrasive then step 2 is a degreasing prep solvent. The reason you do those things first is to prevent the abrasive from driving dirt, oils, and silicone into the paint and metal which causes problems later. Next is mechanically (the abrasive thing) removing loose and visible rust. That is followed by using a rust converter like phosphoric acid that converts any any remaining THIN WELL ADHERED rust (iron oxide) to inert black iron phosohate. Or you can use a dissolver like Evapo Rust instead. Then a final round of detergent and degreaser before applying the coating system. Unless of course you are using a coating product like POR15 that likes a little bit of rust then you follow their directions to the letter. Clear as mud, right?
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Would you recommend sand blasting as a form of abrasion? I have a small hand kit. But basically after you do the final detergent/degreasing you could use the krylon product @TheBoogieman suggest below since it’s a paint and primer.
TheBoogieman said:
View attachment 437036
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Do you have to remove all the factory paint to bare metal if the rust is spotty?

Can’t really use abrasion on the inside of the frame so I assume the Eastwood product I suggested in my first comment is what you’d do instead.
 
Duner said:
Would you recommend sand blasting as a form of abrasion? I have a small hand kit. But basically after you do the final detergent/degreasing you could use the krylon product @TheBoogieman suggest below since it’s a paint and primer.


Do you have to remove all the factory paint to bare metal if the rust is spotty?

Can’t really use abrasion on the inside of the frame so I assume the Eastwood product I suggested in my first comment is what you’d do instead.
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Sand blasting is fine and the only paint you need to remove is if it's loose or has rust underneath. Just be sure to scuff it well enough to remove any gloss.

Lots of people use them but I don't like lacquer and unhardened enamel spray paints. Just not durable enough for my taste. For frames I prefer a product specifically designed for frames or a two part epoxy system. But that's just me.
 
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Duner said:
2) @Irun do you use all of those products or just by brand rustoleum/ krylon?

3) if you use an etch primer is it necessary to have a top coat two in one paint and primer like the suggested krylon brand?
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These are my go-to products, minus a self-etching primer (which I seem to be out of). When you use a self-etching primer it's not necessary to use a all-in-one primer/paint. FWIW, either of the two Rust Reformers will be fine.

20230824_192750.jpg
 
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Irun said:
These are my go-to products, minus a self-etching primer (which I seem to be out of). When you use a self-etching primer it's not necessary to use a all-in-one primer/paint. FWIW, either of the two Rust Reformers will be fine.

View attachment 452535
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Is there any advantage to using a rust reformer vs remover? Sounds like two different ways to skin a cat that can give good results.
 
Duner said:
Is there any advantage to using a rust reformer vs remover? Sounds like two different ways to skin a cat that can give good results.
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As long as the rust is nearly gone (residue that is well adhered) aerosol reformers work okay.
 
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