Should I use these new fenders with rust spots?

[56bugdan]

We’ve had these new aftermarket fenders for probably 20 plus years sitting in the top of my garage. I just got them out to possibly use on a 66 that I’m trying to get done but they have a ton of rust spots through the original black coating. I sanded them down and a lot of the spots are still very visible. My concern is that they’ll cause my paint to lift and blister in 6 months or a year if I use them. Don’t know if sandblasting them will clean it off but I ran 120 grit on my DA and that didn’t take it off. Will epoxy primer seal them enough to stop it from getting worse and causing bubbles in my paint? Is there something else I can seal them with or do I have to cut my losses and just get new ones?

[Chad M]

See if you can lift the staining with some Naval Jelly, or use some rust converter before priming.

[Slow-N-Rusty]

If you have a sandblaster that should take care of it. If the pitting in the rust spots isn't deep you can probably just treat those spots with phosphoric acid (like Ospho) to neutralize the rust.

[74 Thing]

Ospho and a scotchbrite then rinse well. Let dry then epoxy primer.

https://www.youtube.com/watch?v=6HOonWprmdw

[56bugdan]

That sounds like it’ll work and I’m definitely glad I don’t have to scrap these fenders. Especially after seeing how much they’ve gone up in price in recent years. I know some of the newer reproductions are better quality but Damn! These were actually some of the best ones you could get back then so they’re decent. There really isn’t any pitting that I’ve found yet. It’s strange because i can’t feel any of it when I run my hand over it. It’s actually like stains but I’ll try blasting it first and if that doesn’t work I’ll go with the acid. Is Ospho a brand and do ya know where I can pick that up? I know I can get Muriatic Acid at Home Depot but I’ve never looked for phosphoric acid.

[Slow-N-Rusty]

I had to search around to find it locally but managed to find it at Ace Hardware. If you have a Home Depot nearby just grab a gallon of the Klean Strip Concrete and Metal Prep they usually have there. Its a slightly different formulation but it works the same and is much cheaper.

https://www.homedepot.com/p/Klean-Strip-1-Gal-Conc.../100406369

[74 Thing]

Or your local body shop/paint supply store.

There is always Eastwood if you want to order online.

Lowe's or Home Depot as recommended above.

[56bugdan]

Okay, thank you guys. I have a Home Depot and Lowe’s 15 minutes away but the “local” auto body supply is 40 minutes and I’d like to avoid that place if I can because I always find lots of stuff I want when I go in there and a $40 trip ends up being $300. If I had no choice I’d go there but the wife wouldn’t be happy when I coulda just bought new fenders for what I end up spending there.

[Mike Fisher]

If you had wiped phosphoric acid on them before they went in the rafters bare metal they wouldn't have rusted.
_________________
https://imgur.com/user/FisherSquareback/posts
69 FI/AT square Daily Driver
66 sunroof,67,70,71,71,71AT,72,72AT,73 Parts
two 57 oval ragtops sold
'68 Karmann Ghia sold

Society is like stew. If you don't keep it stirred up you end up with a lot of scum on the top! - Russ_Wolfe/Edward Abbey

[56bugdan]

They actually weren’t bare metal when I put em away. They had that EDP electro-deposit primer that they come with so I figured they’d be okay since it’s a dry space but I guess just humidity can get to them when they sit that long. And thank you, I didn’t know that phospho will prevent flash rust on bare metal. I’m gonna pick some up for the future. I’ll use it when I need to leave some parts bare for a couple nights.

[Mike Fisher]

Yeah, looking at them again they would have rusted Everywhere if they were bare metal.
_________________
https://imgur.com/user/FisherSquareback/posts
69 FI/AT square Daily Driver
66 sunroof,67,70,71,71,71AT,72,72AT,73 Parts
two 57 oval ragtops sold
'68 Karmann Ghia sold

Society is like stew. If you don't keep it stirred up you end up with a lot of scum on the top! - Russ_Wolfe/Edward Abbey

[Chickensoup]

nope those are too far gone. send them to me.
_________________
-'85 c10 5.3 LS, 222 cam, long tubes, x pipe, 3 inch spin tech's
-'05 B5.5 TDI Wagon 17in sport rims ;EGR + BSM + ASV Delete, Stage-2 Tune, straight pipe
'65 Tourist Delivery Build
'66 RIP
'69 RIP
Hosea 4:6 "My people are destroyed for lack of knowledge"

[56bugdan]

HaHa okay, they’re on their way! Thanks for the help.