Speed of Tapping Head?

Hi,

I'm looking at constructing a small electronic tapping head for my Taig CNC
Mill. By electronic, I mean that the tapping head will be driven by a small
12 dc motor geared down to an appropriate speed. The direction will be
controlled by micro switches and possibly a PIC microprocessor.

The tapping head is to tap up to 6mm (1/4"), and if I can 8mm. My question
is:

What is an appropriate speed for a tapping head?

Thanks in advance.

Peter Homann
<mailto:peter.homann@...>
Work : +61 3 8530-7755
Adacel Technologies Ltd Fax : +61 3 9596-2960
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