Hello,

I know you can get a black "paint" to paint over rust, but how does it
work and is it any better than using normal gloss paint? Presumably
forming a barrier to stop water getting in is half the battle?

The one I have seen is bizarrely water based, I would have thought
water is the last thing you want to apply to rust! I know they are not
quite the same but the Ronseal and Hammerite metal paints that are
supposed to stop rust forming in the first place require a special
solvent, don't they.

Thanks.