along the dotted line, removing the right portion
of the foot. After cutting, the edges should be filed
down to a smooth round finish.
Parachute harness and webbing sewing is
classified as a major repair. However, there are
various other sewing projects requiring webbing
sewing.
ROTARY SEWING MACHINES
Some of the most commonly used rotary
sewing machines are the class 111 W series.
They are the type used to teach basic sewing in
PR “A” school, and can be found in almost any
PR shop.
CLASS 111 SEWING MACHINES
The class 111 sewing machines are one line
(single needle) lockstitch machines designed to sew
medium weight and heavyweight material. They
are capable of sewing at a speed of approximately
3,000 stitches per minute (spin). The lockstitch is
formed in the bobbin assembly by the rotary hook
on the 111 machines. The class 111 machine is
commonly used for sewing aircraft protective
covers, upholstery, and soundproofing.
DIFFERENT MODELS OF THE
111 W SEWING MACHINE
The following text discusses the various
models of the 111 W sewing machine.
111 W 150 Sewing Machine
The 111 W 150 sewing machine is a
high-speed, single-needle, lockstitch, compound
feed machine employing a gear-driven rotary
hook with a vertical axis.
It is designed
for sewing medium weight fabrics such as
239.281
Figure 9-24A.—Class 111 sewing machine, front view showing oiling points.
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