Originally Posted by buildbright
A claybar is fine on glass with proper lubrication. Detailers use it all the time to remove water spots. I get great results with it all the time. Its very easy and anyone can do it.
Glass is much harder than paint. Hence why paint polish won't correct glass and the need for Cerium Oxide.
This is something many folks fail to understand which is why I warn against it unless you really understand how to do it properly. Water spots are nothing more than a build-up of lime, calcium and other minerals on the surface of the glass. They're not defects or scratches in
the glass itself that you're trying to "polish" out.
My point was that people automatically think of glass as being really hard and durable. They don't understand that something as simple as rubbing against glass coated with dirt, sand or anything abrasive can scratch and gouge the glass fairly easily. And it's not a simple matter to "buff it out".