Paragraph 2 2B001
Sub—head c.1. of this entry does not specify machines designed specifically as jig grinders having both of the following characteristics:
a.
Axes limited to x, y, c and a, where the c axis is used to maintain the grinding wheel normal to the work surface and the a axis is configured to grind barrel cams; and
b.
A spindle run out not less (not better) than 0·0006mm.