Scraping noise from rear wheel - now gone?

[CommanderJameson]

Driving along in town, I noticed a scraping noise (with the kind of resonance that makes one think the brake disc is involved). It was quite loud - clearly audible from within the car with the windows up.

I called a chum who helped me have a look at the oily bits (I can take the wheel off right enough, but I don't really know what I'm looking at or for after that) and, although he heard it on a short test run, it stopped, and hasn't recurred. He concurred with my initial opinion that it was coming from the nearside rear.

We popped the rear wheels off and he had a good peer at the brakes and disc - no evidence of anything could be seen. Pads and discs are under a year and 10,000 miles old.

So, my question is this: is this a worry? Is it likely to have just been a foreign body trapped between something and the disc, which has now gone, or should I pay a man with more spanner skills than me to take things to bits?

[blondini]

I wouldn't worry. It was probably just a stone trapped between the disc and backplate.

[phelix]

Or parked up such that the nearside was more exposed to the rain/weather and got a bit of surface rust.

[CommanderJameson]

phelix said:

Or parked up such that the nearside was more exposed to the rain/weather and got a bit of surface rust.

The car's been used every day this week - is it a valid assumption that the 20 hours or so it was stood idle (i.e. from early evening Friday to Saturday lunchtime) wouldn't have been enough to build up sufficient rust to make this sort of noise?

[phelix]

It can happen - on a windy rainy day you can see different amounts of surface rust depending on whether it's the windward or leeward side. This rust usually wears off quickly. But if water gets driven between the disc and pad they can be almost welded together, albeit lightly. This high spot will take also wear away quickly but might make some noise first.