So, the 30 micro corresponds to 600 grit. This is the first sheet in my pack. I've been doing 40 laps on each side of the blade. This sheet is followed by 12, 9, 3, 1 which corresponds to 1000, 1800, 8000, 14,000. the last two films are .3, and .5 micron. My question would be if all these sheets are even necessary and if so, what is the advantage to the edge?