TM 1-1500-204-23-8
NOTE
Before drilling, work must be set up, a sharp drill
bit of the correct size selected, and the machine
set for the correct cutting speed and feed.
(a) Align drill bit with center punch mark of the
hole to be drilled.
(b) Feed drill bit into piece until it has penetrated
approximately two-thirds of the diameter of the drill.
(c) Remove drill bit and check the relation of the
drilled spot to the scribed layout circle.
(d) When the spot and the layout circle are
concentric, the hole can be drilled to the required depth.
(3) Inspection and maintenance. Refer to the
applicable maintenance manuals for inspection and
maintenance of drilling machines.
b.
Bandsaws.
The bandsaws, as shown in figures
2-2 and 2-3, use metal-cutting bandsaw blades to cut off
to length, bar stock and structural steel sections.
(1) Types. The vertical contour and cutoff type
bandsaws are the primary types used in aircraft main-
tenance. Both machines have different makes and
models, but basic features are similar.
(2) Operating procedures. Refer to the specific
bandsaw operator's manual for operating procedures. Be
sure to adjust cutting speed, feed rate, and feed pressure
prior to cutting.
(3) Inspection and maintenance. Refer to the
applicable maintenance manuals for inspection and
maintenance of bandsaws. Blade must be adjusted to
recommended tension. Be sure to check blade tracking
and alignment within saw guides.
c.
Lathes. The lathe, as shown in figure 2-4, is a
machine in which work is rotated about a horizontal axis
and cut or shaped by a fixed tool.
(1) Types. The engine, turret, production, and
vertical lathes are typical types used for cutting or
shaping.
(2) Operating procedures. Refer to the specific
lathe operator's manual for operating procedures.
(3) Inspection and maintenance. Refer to the
applicable maintenance manuals for inspection and
maintenance of lathes.
d. Milling Machines. The milling machine, as shown
in figure 2-5, is a machine on which metal is shaped and
dressed by rotating milling cutters.
(1) Types. Milling machines have different
makes and models, but basic features are similar.
(2) Operating procedures. Refer to the specific
milling
machine
operator's
manual
for
operating
procedures.
(3) Inspection and maintenance. Refer to the
applicable maintenance manuals for inspection and
maintenance of milling machines.
e. Shapers. The shaper, as shown in figure 2-6, is
used to form and shape a workpiece.
(1) Types. Shapers have different makes and
models but basic features are similar.
(2) Operating procedures. Refer to the specific
shaper operator's manual for operating procedures.
(3) Inspection and maintenance. Refer to the
applicable maintenance manuals for inspection and
maintenance of shapers.
f. Grinders. Grinders, as shown in figure 2-7, are
used to grind material to a specific tolerance.
(1) Types: There are two basic types of grinders:
a bench type and a pedestal type. These grinders consist
of an electric motor with a grinding wheel attached to
each end of the motor shaft. One wheel is coarse, for
rough work; the other is fine and is used for sharpening
purposes.
2-5
