Originally Posted by
johnnyspaghetti
Some grades of stainless will rust. I won't pretend to know much about metallurgy. It won't rust severely ever or lose measurable strength.
A better way to put it is that stainless steels will rust in some environments.
Originally Posted by
wschruba
As the chromium in alloy is "used up" (not really what happens), stainless will, indeed, begin to rust. It takes a good measure of time to happen, and that's not to say that it isn't a good thing to use, just that it isn't a panacea.
Um...no. The chromium won't be "used up". Even if it did oxidized completely, chromium oxides are green not red like rust. It's the iron that oxidizes and forms rust.
Originally Posted by
wschruba
Maybe he'll wind up changing the cables every couple of years, rather than every year. It's hard to say, as it is super dependant on local conditions. A bike with stainless cables may go years without rust forming in the desert, or months next to the sea, if stored outside.
The differences in the two scenarios above is chloride ions (from salt) and water. You could expose the stainless to salt in the desert but there isn't enough water in the air for the salt to absorb it and start plucking iron atoms out of the steel. In an ocean environment, there is plenty of both. If you were to put the bike in a humid environment without much salt exposure, it would last a long time as well.
Originally Posted by
El Gato27
Prepping a bike for my son for campus use at a major college (~55,000 enrollment). The bike will be parked on campus, outdoors. Thinking of switching out the working brake and derailleur cables for stainless to keep the cables from rusting. Was wondering if stainless eventually rusts? Bike will be used ~3-4 miles per day.
It may. But another thing to consider is the inside of the cable housing. Higher quality cable housing is lined with a plastic liner so that it doesn't rust as well. A stainless cable with unlined housing won't stand up to the elements as well.
Originally Posted by
SHBR
I have a teflon coated stainless steel rear der. cable on my beater bike that lives outside locked to a pole in the elements.
Yup. That helps as well. A teflon coated inner cable with a plastic lined housing will resist corrosion the best...even with salt exposure.