"Lloyd E. Sponenburgh" lloydspinsidemindspring.com wrote in message
.70...
I've been learning on the Darex E90. It's very easy to use, but it
took
a while to figure out exactly how to adjust the stylus height and
position vs. the wheel location in order to duplicate the original
factory primary relief angle on a given cutter.

0.5" times the sine of 1 degree is about 0.008", so for a flat-cutting
cup or dish wheel you lower the finger below the tool's center height
by 0.008" times the angle times the diameter of the cutter. Lowering
the spring finger 0.040" rotates a 1" cutter by 5 degrees (close
enough for mental math and cutter relief).

For a round wheel you leave the finger at tool center height and raise
the wheel 0.008" times the relief angle, times the wheel diameter.

jsw