MILLING MACHINE OPERATIONS - OD1644 - LESSON 1/TASK 2
others have helical teeth. Some cutters have mounting shanks, others have
mounting holes. The machine operator must decide which cutter to use. To
make this decision, he must be familiar with various types of cutters and
Standard milling cutters are made in many shapes and sizes for
milling both regular and irregular shapes.
Various cutters designed for
specific purposes also are available.
various widths and diameters, used principally for milling flat surfaces
which are parallel to the axis to the cutter; (2) angular milling cutters,
designed for milling V-grooves and the grooves in reamers, taps, and milling
cutters; (3) face milling cutters, used for milling flat surfaces at right
angles to the axis of the cutter; and (4) forming cutters, used for the
production of surfaces with some form of irregular outline.
Milling cutters may also be classified as arbor-mounted, or shank-
Arbor-mounted cutters are mounted on the straight shanks of an
arbor. The arbor is then inserted into the milling machine spindle.
Milling cutters may have straight, right-hand, left-hand, or
staggered teeth. Straight teeth are parallel to the axis of the cutter. If
a helix angle twists in a clockwise direction, the cutter has right-hand
If the helix angle twists in a counterclockwise direction, the
cutter has left-hand teeth.
The teeth on staggered-tooth cutters are
alternately left-hand and right-hand.
Milling Cutter Nomenclature.
Figure 23 on the following page shows
two views of a common milling cutter with its parts and angles identified.
These parts and angles are common to all types of cutters in some form.
Pitch. The pitch refers to the angular distance between like parts
on the adjacent teeth. The pitch is determined by the number of teeth.
Face of Tooth. The tooth face is the forward facing surface of the
tooth which forms the cutting edge.