(1/2 to 360) around its circumference. You can turn
to the table of the milling machine. The base of the
the table by hand or by the table feed mechanism
rotatable type is graduated in degrees. This feature
through a gear train, as shown in figure 7-11. An 80
allows you to machine compound angles. The
to 1 worm and gear drive contained in the rotary table
toolmaker's knee has a tilting surface with a built-in
and index plate arrangement makes this device useful
protractor head graduated in degrees to set the table or
for accurate indexing of horizontal surfaces.
a vernier scale for more accurate settings.
INDEXING EQUIPMENT
CIRCULAR MILLING ATTACHMENT
Indexing equipment (fig. 7-12) is used to hold and
The circular milling attachment, or rotary table
turn the workpiece so that a number of accurately
(fig. 7-11), is used to set up work that must be rotated
in a horizontal plane. The worktable is graduated
spaced cuts can be made (gear teeth for example).
Figure 7-11.--Circular milling attachment with power feed mechanism.
7-8