dsc wrote:I haven't but I don't know anything about the method used for getting those distribution graphs. Was this done using sifting or microscopy photography or a mixture of both?
Also was this done a single grinder with a VFD, something custom built or on different grinders with different burrs sets?
Presumably this is laser diffractometry, done on a single grinder (as noted by the OP). If they used different grinders, then any comparison of the three distribution curves is worthless. No idea how they varied the rpm, or what slow/medium/high speed means.