In some cases, a scarifier/grinder can be used to remove old paint. Scarifiers employ various types of "cutters" on a rotating drum, which knock paint loose from concrete with a slapping action. The harder carbide cutters remove paint faster and last longer, but they tend to "scar" the surface a little more than a softer steel cutter.	Removing paint with a scarifier. We usually use this method as preparation for a restripe, when there is excessive build-up or flaking paint. If a customer wants to completely remove markings, we usually follow with a pressure washer or wet sandblaster.
Moisture is the biggest enemy of traffic paint. The worst areas are usually against curbs or in shaded areas.	As you can see, the scarifier does tend to leave marks from the cutters. The dirtier the concrete the more visible they will be. They can usually be minimized, with a good cleaning or with a little traffic on the area.