Have you all ever done anything to protect your bare brake rotors from corrosion while the car sits - outside - long-term?

I'm looking for advice on actual experiences from having done something to protect the bare iron from corrosion.
Some posts online suggest spraying a thin coating of primer, that the brake pads will easily wear off when the car is used again.
I'd like to know if anyone here has actually dealt with the issue, or discovered anything useful.
Put the car on jack stands, remove the wheels and wrap the brakes in plastic?

BACKGROUND: I've got a buddy with a second home and a car he leaves there, outside, for like 9 months out of the year. He and his family fly there, take a cab from the airport to the property where the car sits. In the past, the issue hasn't been important because the car was 20 years old, just basic transportation, and they'd visit there maybe 5-6 times year, the brakes never got real bad. Now, he needs to replace the old car and he knows he'll be visiting less, maybe just twice a year, so he's looking for ways to sort of protect his investment. Inside storage isn't a realistic option.

PS - I told him to forget buying another car. Just hire a rental when he arrives at the airport.
For the same cost as buying a decent car, he could rent a car for 10 years worth of visits.

Thanks,
- Art

I've never worried about it. So you get a little surface flash rusting, one stop, it's gone. This, versus trying to apply a coating that would actually do some good in a less than optimum environment?

I don't know if I would worry about it, beyond getting brake fluid flushed every couple of years.
I know I left my car parked 6 to 9 months at a time for about 4 years with no real issues.
near the sea even.
Deployed 9 months out of the first year and about that much every year after that, except dry dock work.
we never bothered to do anything except disconnect batteries and park it in the long term storage lot.
Both in California and Washington state, so pretty extreme on both count, weather wise.
tropical might be an issue for bugs living inside the cars, but rust shouldn't be any more extreme.

Not really easy to apply but zinc dust spray is used for this on some euro imports when stored at the ports. It burns off when brakes are finally used. But messy to apply and not exactly easy if you have a solid rim to get around.

To the OP - I too have wondered about this same thing. Like if you could spray something similar to Armor All - just something that would displace moisture - you'd spray it all over the brake calipers, rotors, drums, etc. BUT, it would need to be able to rinse off with water. Also, something that would not contaminate the brake pads/shoes. Oil would contaminate them, & Armor All would too because of the silicone.

The rental car sure makes more sense to me then upkeep on a vehicle you use 2x a year for a week or so.

Past that, I had a 4x4 truck that only got used a few times a year, when not in use, it was parked on the grass on my side lot. Grass is about the worst parking surface for a vehicle to sit on long term. Even on the grass, it took almost 7 years before the rotors were damaged enough to have any effect on function, the truck body and frame were in worst condition then the brakes ever were.

If he buys a "new" car to have sit, maybe buy an extra set of rotors to sit on the shelf inside of the building, to replace the original rotors after then get bad enough to need replacement.

Thanks guys,
I appreciate the very useful input.

@njmopar, cool.. I never knew that - but I've used high-zinc primer on aircraft applications, back when I was working in that field, and it was a protectant we could just leave as a coating, or use as a primer for finished paint.
@Sunroofcuda - Yeah, I wouldn't use anything that is absorbent, or that doesn't completely dry.. Even though ArmorAll is soap-based and should just rinse off, I'd be afraid of it sucking into the brake pads and even if it didn't affect the brake pads performance, they might just stink all the time..

For the effort it would take each time to spray the rotors outside and inside (He'd have to buy a jack, and tire chocks, and probably jack stands, then store them somewhere).. I'll advise him to simply not worry about it and buy a set of cheap spare rotors to have on the shelf.

The Nuclear Option: Get a car with carbon fiber or ceramic rotors!

Cheers,
- Art

unless the indoor storage is extremely humid, like may be found on a coastal area, i'm almost certain all you will find is a light coating of very fine surface rust.
as others have said, a few slow stops will have the rotors back in shape.
as to having rotors on the shelf, i have a couple of sets of those for my caravan.
as i turn my own rotors on a real lathe, i came to discover if one makes an arbor that the rotor bolts to as when it is in use, it only takes a couple of thousandths of a cut to true it up.
i sand blast them first and paint the hub, the back side, and between the fins [just hose the devil in there !] with black epoxy appliance paint.
i realize most can't do this. just commenting on what works for me.
your mileage will vary.

Not sure about the rental car comments. We just got back from Utah. Rented a SUV for the 5 of us....$850/week. If he spends a couple three weeks at his 2nd home that could add up quick!

It's a tough equation to solve without knowing the numbers:
What's a car the person considers "decent" going to cost ?
Does it make sense to drive rather than fly to the 2nd home ?
Is there someone in the area who can help, either with a car or checking the car left behind ?
Does it make sense to keep the old car ?
Is there an inside storage facility in the area, and its monthly/yearly cost ?

When I lived in South Jersey, I had tools & a car in a Public Storage bldg; more humid than I'd thought, and some of the tools rusted badly.
Didn't really affect the car at all, except some very slight corrosion on the aluminum parts underhood after 2 years.
Never bothered the rotors or anything else.
That place was nearly wet inside at times.

wet inside a lot of the time is not good !
mold likes that, and can really mess up the interior.
it is kind of funny though, in an atmosphere like that, some things rust badly while others do not. gives one something to scratch his head in pondering.

Maybe in Arizona, I had them rust up to the point you can move the vehicle(under power). You need to coat them with something to keep them from rusting. But you will have to remove it when you plan on driving it again. This stuff looks good...

https://www.amazon.com/RPM-Rust-Pre...&hvtargid=pla-568707699769&psc=1

Depends greatly on the climate where it’s parked. NY is wet.

And cheap rotors are not worth buying.