What can I do to "clean up" the rust on my rotors :(

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What can I do to "clean up" the rust on my rotors :(

Post by GRNSHRK »

Hi guys, with the wheels off and some time on my hands, I'd like to do something with the rusted edges and whatnot on my rotors, but not sure what to do :-?

I was thinking I could use something like POR15 and just coat the edges and exposed surfaces to at least they look better [-o<

Any thoughts or suggestions [-o<

TIA, as always :wink:
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Re: What can I do to "clean up" the rust on my rotors :(

Post by Tommys 89 635 »

Hey Bobbo,

Clean it with a wire brush then a hi temp spray paint
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Re: What can I do to "clean up" the rust on my rotors :(

Post by GRNSHRK »

Hey Tommy, I don't plan on removing the rotors, I was hoping to apply something while they are still installed [-o<

Wow, crickets otherwise :(

Surprised the collective wisdom of the board doesn't have any other ideas :-({|=
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Re: What can I do to "clean up" the rust on my rotors :(

Post by Jlc »

Wood bleach? I use it to clean rust off of barrel staves when I am getting rid of water stains on bourbon barrels; but it is nasty stuff from a health standpoint and I am not sure if you'd wnat it on your rotors.
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Re: What can I do to "clean up" the rust on my rotors :(

Post by hornhospital »

A 3" or 4" wire wheel with a drive axle to use it in a drill motor works very well (but wear goggles). Once brushed clean of rust use a paint brush to apply silver Rustoleum. I've never had it burn off even on heavily used brakes.
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Re: What can I do to "clean up" the rust on my rotors :(

Post by plip1953 »

Pretty much as already suggested, wire brush any loose stuff and then apply something like POR15. I did mines donkey's years ago and rust has never broken back through.

And while I guess you can do the same with the rotor edges, I personally wouldn't bother, as in any case it might more readily get burnt off o/a heat (which of course will be highest at the rotor edges).
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Re: What can I do to "clean up" the rust on my rotors :(

Post by Tommys 89 635 »

GRNSHRK wrote: Wed Dec 09, 2020 9:07 pm Hey Tommy, I don't plan on removing the rotors, I was hoping to apply something while they are still installed [-o<

Hey Bob,

You don't need to take the rotors off. Cover the caliper, use the wire brush to clean off the rust spots and spray a few thin coats.
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Re: What can I do to "clean up" the rust on my rotors :(

Post by bpoliakoff »

Bobbo Go to Home Depot and get a "Flap Wheel" for a drill. Much more effective that a wire brush, It is strips of course emery paper bonded together almost like a grinding wheel type thing that won't make make a mess like a grinding wheel. I learned about when grinding the boogers from welding when doing the body work on my car. A great tool to know of and way better than a wire brush.
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Re: What can I do to "clean up" the rust on my rotors :(

Post by 86_6series »

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Re: What can I do to "clean up" the rust on my rotors :(

Post by GRNSHRK »

Thanks guys, now that's more like it =D>

Never heard of a flap wheel either, so off to Home Depot I go :shock:

Or probably Lowe's, like them much better :roll:

But I think the POR15 is the way to go over painting, plus it's gray in color from what I recall, so it should "match" pretty well [-o<

Thanks again gents :lol:

Got the TS wheel covers back from the paint shop yesterday, they look awesome but still waiting on new adhesive for the old school Motorsport emblems that will be going on as well :-"
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Re: What can I do to "clean up" the rust on my rotors :(

Post by bpoliakoff »

Ya want grey in color?? Go to your local auto paint supply and get a rattle can oif "Cast Blast" Looks like cast metal and will give you the look you want stands up to heat as well.
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Re: What can I do to "clean up" the rust on my rotors :(

Post by jps635 »

This https://www.eastwood.com/eastwood-brake ... rosol.html

Have used lots including sump and bell-housing. Is a quality product and best paint for the job
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Re: What can I do to "clean up" the rust on my rotors :(

Post by redrumm3 »

If Home Depot doesn't have a flap wheel in stock, go to McMaster-Carr.com. They have everything! I've bought from them for years.
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Re: What can I do to "clean up" the rust on my rotors :(

Post by bpoliakoff »

I work part time at Home Depot in the hardware dept. They have them. One for a drill with a shaft on it and all kinds of various grit for an angle grinder which is a tool you guys should have. They do sell a cheap Ryobi angle grinder for around $36
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Re: What can I do to "clean up" the rust on my rotors :(

Post by Da_Hose »

Hey Bobbo,

Flap wheels actually remove material, while wire wheels knock off surface stuff with less reduction of the substrate. I would stick with wire wheel cleanup. I used VHT caliper/disk paint, and the the hats on my rotors still look glossy and black years later. I even painted the rear drums on my 02 that way 25+ years ago. I haven't driven it for more than 15 years now, but even sitting out in the weather, the drums are still glossy.

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Re: What can I do to "clean up" the rust on my rotors :(

Post by GRNSHRK »

I did buy a flap wheel at Lowe's, but haven't tried it yet :-?

I also have a wire wheel of sorts, although it's shaped more like a cone than a wheel :roll:

Gonna give that I try as well [-o<

And I was only thinking gray because I think that's what color POR15 is, and would match the original cat iron color a bit more, I guess :-k

Plus painting usually requires a clean surface for the paint to adhere to, while POR15 should bond, even if I don't get rid of all the rust [-o<

Hopefully will get back in the garage tomorrow, pouring rain right now :(

Of course, California desperately needs it =D>
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Re: What can I do to "clean up" the rust on my rotors :(

Post by bpoliakoff »

Cast blast. !! Takes heat and a great grey color. Did my calipers with it and am very happy.
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Re: What can I do to "clean up" the rust on my rotors :(

Post by GRNSHRK »

Ok, this job is now complete, takes forever to get things delivered these days ](*,)

I did have black POR-15, but opted for silver, to sorta match the appearance of the portion of the rotors that are swept by the brake pads :-"

This stuff is so shiny that you can see the reflection of the cross drilled holes in the rotors in the finish :shock:

I didn't bother with the faces, which won't be seen once the wheels are installed :roll:

Glad this is done, please check out my thread regarding the Throwing Star wheel redo in the "Wheels and Tires" forum \:D/
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Re: What can I do to "clean up" the rust on my rotors :(

Post by plip1953 »

They look good. You're quite right not to paint the wheel mating surface, although it is important that this is spotlessly clean and free of corrosion or dirt, both in order to give the best possible connection between hub and wheel, and also to take away any possibility of causing unwanted disc runout. Having done the cleaning, I generally smear a very small amount of copper grease over the surface to make it less likely that wheel and hub might subsequently bond themselves together due to galvanic corrosion.
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Re: What can I do to "clean up" the rust on my rotors :(

Post by GRNSHRK »

Thanks Phil, good points but while they do appear to have some rust on them, I don't have to deal with the corrosion issues here in California like you guys do in the UK :-"

Done deal for now, don't think I'll have the wheels back off anytime soon :roll:
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