Machinery Repairman

drill press and the radial drill press. These machines
have similar operating characteristics but differ in that
you position the drilling lead on the radial drill, and
you position the workpiece on the upright drill.
UPRIGHT DRILL PRESSES
Upright drill presses discussed in this section will
be the general purpose, the heavy duty, and the
sensitive drill presses. Nearly all ships have one or
more of these types. They are classified primarily by
the size of drill that can be used, and by the size of the
work that can be set up.
General Purpose Drill Press (Round Column)
Shown in figure 4-24, the general purpose drill
press is the most common type of machine found in
Navy machine shops. The basic components of this
machine are shown in the illustration.
The base has a machined surface with T-slots for
heavy or bulky work.
Figure 4-24.—General purpose drill press.
4-15
The column supports the work table, the drive
mechanism and the spindle head.
The work table and arm can be swiveled around
the column and can be moved up or down to adjust for
height. In addition, the work table may be rotated
360° about its own center.
The spindle head guides and supports the spindle
and can be adjusted vertically to provide maximum
support near the spindle socket.
The spindle is a splined shaft with a Morse taper
socket to hold the drill. The spline permits vertical
movement of the spindle while it is rotating.
The drive mechanism includes the motor, speed
and feed change gears, and mechanical controls.
Heavy Duty Drill Press (Box Columns)
The heavy duty drill press (fig. 4-25) is normally
used to drill large holes. It differs from the general
purpose drill press in that the work table moves only
Figure 4-25.—Heavy duty drill press.
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