new rotors after rain

no1000 · 05-03-03, 01:42

i upgraded my brake system for the race track this summer but it seems after 2 weeks of rain my new rotors are starting to show some rusting, how to clean?, without using harsh chemical i don't mind scrubing them.
kal

Ben Carufel · 05-03-03, 02:11

You can scrub/brush all you want, the rust will just come back.

Best thing to do (what most of the Bimmer guys do) is take them off, rough them up with some 320 grit (the 3M flexible sanding sponges are awesome for this), mask off the face and paint the hat with a high-temperature light-gray paint. Most people have found that silver paints just don't have what it takes, so light-gray is the color of choice.

I suppose you could do it on the car, too, you'd just have to be way more careful with masking. I personally do it as soon as I buy a new set of rotors before I put them into storage in my workbench -- keeps the hats from rusting due to moisture in the air. I tend to buy my rotors when the particular type I want are on special at my local BMW/Porsche aftermarket shop.

Taxlady · 05-03-03, 12:24

I'm gonna ask a dumb question. Which part is the "hat"? Is it the rusty bit in the second photo? The round part with no holes?

Sci-Fi · 05-03-03, 02:42

Quote:

Originally posted by Taxlady
I'm gonna ask a dumb question. Which part is the "hat"? Is it the rusty bit in the second photo? The round part with no holes?

The "Hat" is the center black piece seen in the pic below:

Some rotors have or can be cad plated or powder coated to prevent rust from forming on the non-contact surfaces. But longevity of the coating varies and may become an issue.

Taxlady · 05-03-03, 02:54

Thanks guys.

4DSC · 05-03-03, 02:58

I just call that the "hub" since.... umm... that's where the hub is...

no1000 · 05-03-03, 05:58

actually the rusting area is part of the rotors not the hub diffrent from the picture but it's called hub.

i called couple places and they offer to zinc wash or nickel plate them for me which will prevent the rotors from rusting but it won't last for a long time.
and any comment ?.

now i wonder why nobody mention this when i bought the rotors
daaam you retailers

kal

Intermezzo · 05-03-03, 07:26

Yes, zinc plated hats/hubs are supposed to retard the rusting, but I heard it still rusts after a while. Before I have my Brembo's installed, I'm going to try Ben Carufel's tip.

4DSC · 05-04-03, 12:09

Luster does the same trick and posted some very pretty pics of them. A while back.

He doesn't bother masking the rotors either because he says the paint wears off right away.

bet993 · 05-05-03, 04:13

Why doesn't the pad and caliper cover the entire rotor surface? If I am looking at the picture correctly, it seems odd that the pad is only using half of the rotor surface.

Luster · 05-05-03, 04:40

Quote:

Originally posted by 4DSC
Luster does the same trick and posted some very pretty pics of them. A while back. He doesn't bother masking the rotors either because he says the paint wears off right away.

Yes, each time I rotate the tires, I just lightly sand off the rust and shoot a little hi-temp Silver on the rotors.

Makes them look like new again (especially after a long salty winter!)

Light grey is also a nice look!

flyby · 05-06-03, 01:56

putting paint on the rotor area that the pads touch is not a good thing