Hi Art,
If I understand what you say about Mach2, it measures inaccurately
placed sensors and compensates for that potential problem.
Suppose one has a motor pulley that has a few thou (") runout and
not running at 1 to 1 ratio.
So, on the first measured rev, although the sensors may be perfectly
spaced, Mach2 thinks they are not. On the next partial rev it thinks
that the rotational speed has varied, which may or may not be true.
If my thinking is right, multiple sensors would make my thread
cutting worse, or ??
Jerry