Tc 9-524 fundamentals of machine tools

PLAIN MILLING
General
Plain milling, also called surface milling or slab milling, is
milling flat surfaces with the milling cutter axis parallel to
the surface being milled. Generally, plain milling is done
with the workpiece surface mounted parallel to the surface of
the milling machine table and the milling cutter mounted on
a standard milling machine arbor. The arbor is well supported
in a horizontal plane between the milling machine spindle
and one or more arbor supports.
Mounting the Workpiece
The workpiece is generally clamped directly to the table or
supported in a vise for plain milling. The milling machine
table should be checked for alignment before starting to cut. If
the workpiece surface to be milled is at an angle to the base
plane of the piece, the workpiece should be mounted in a
universal vise or on an adjustable angle plate. The holding
device should be adjusted so that the workpiece surface is
parallel to the table of the milling machine.
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TC 9-524
Selecting the Cutter
A careful study of the drawing must be made to determine
what cutter is best suited for the job. Flat surfaces may be
milled with a plain milling cutter mounted on an arbor.
Deeper cuts may generally be taken when using narrow cutters
than with wide cutters. The choice of milling cutters should be
based on the size and shape of the workpiece. If a wide area is
to be milled, fewer traverses will be required using a wide
cutter. If large quantities of metal are to be removed, a coarse
tooth cutter should be used for roughing and a finer tooth
cutter should be used for finishing. A relatively slow cutting
speed and fast table feed should be used for roughing, and a
relatively fast cutting speed and slow table feed used for
finishing. The surface should be checked for accuracy after