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It is heavily recommended that you not skip a grit in the processing sequence, and when transitioning from metal bonded abrasives to resin bonded abrasives the first resin bond grit abrasive used must be one grit lower than the last metal grit abrasive used. In rare situations you may be able to skip a grit or not drop back a grit, but it can never be used as a standard rule. If you do attempt to skip a step in the polishing process, you should perform comparison testing in several areas of the slab to determine what type of quality you are giving up by skipping a grit or not dropping back a grit.

It will be up to the contractor to determine at what grit to start the process since he or she knows the goal to reach. The following example is an accepted grit sequence depending on the concrete surface given to work with:

Start with a metal 50 or 70 grit, two or three segments per abrasive. Move up to a 100 or 120 grit with six segments per abrasive. Switching from a two or three segment to a six segment abrasive allows the concrete surface to be closed up and refined as quickly as possible to obtain the best clarity of reflection and durability. The more surface area an abrasive has, the faster the surface of the concrete will be closed. There are situations where you may need to go higher in metal bond abrasives and situations where metal bond abrasives are not needed.

Now it's time to move to the resin abrasives, remembering to drop back one grit. A typical sequence would be: 30/50,100/120, 200/220, 400, 800, 1,500/1,800 and 3,000/3,500.

All of the resin bonded diamonds are full faced diamonds that close up the surface of the concrete quickly to obtain the best clarity of reflection and durability. Depending on your desired results, you may stop at any grit.