Jules,
Two weeks max, usually quicker.

Phil,
You cannot do that, as the inner bead (that is coated) is the same height as the exposed metal flat areas, so would also end up without it's coating . Just ask PON, he fucked his up by trying to do this with a sander . Even masking it all off and using one of those Black and Decker Mice takes a good few hours - it is more economical to machine in labour costs.