This is a very common question. The bigger the grit size, the bigger the line or pit (imperfection) results on the material. That imperfection is rated and given an RMS or RA number. Below we have a quick chart to show you what the expected finish of the material should be when using a particular grit size. These finishes can vary according to many factors including but not limited to the type of material, wet or dry grinding, RPMs, and depth of cut, among other application details.
|Eagle Grit Size||FEPA Grit Size||Expected RMS