Civil Engineering Reference
In-Depth Information
Fig. 10.4. A gear cutter.
MINIMUM MOVEMENT
Because a dividing head can rotate, the chances are that the work does not
need moving by a large amount. In fact, virtually all dividing head work can
be done with a movement of no more than 50 per cent of the maximum work
diameter called for.
As mentioned earlier, to pitch out large diameters, where you cannot get
the work under the dividing head, can be fairly easy. Just tilt the dividing head
at 45 degrees and tilt the milling machine head by the same amount so they
are facing each other. Use a test indicator to clock the large diameter so the
dividing head is on the centre line of the spindle both horizontally and vertic-
ally, and all you need to do is move the milling machine by the radius of the
PCD you require which will give you the PCD you desire. As the milling ma-
chine spindle remains on the vertical centreline it is a simple job to pitch out
all the holes.
