Figure 4-19.—Feed-driving eccentric.
the timing and adjustment procedures for the
31-15 sewing machine.
DISASSEMBLY AND REASSEMBLY
OF THE 1ll W 155
SEWING MACHINE
You probably will never need to take the lll
W 155 class sewing machine completely apart, but
you may need to replace some parts. Therefore,
you need to know the procedures for disassem-
bling and reassembling the 111 W 155 sewing
machine.
The following are some helpful hints that you
should remember while working on disassembly
and reassembly of any sewing machine:
. All sewing machine screws have a c a s e -
hardened surface, which must be removed by
grinding should it become necessary to use an
easyout to remove the screw.
. Using grinding compound is recommended
when you are replacing parts that attach to a
shaft. Place a small amount of grinding com-
pound on the shaft and rotate the part on the shaft
until it moves freely. (Remove all grinding
compound before you reassemble the parts.)
l Oiling is a must in the reassembly of parts.
A generous amount of 10W mineral oil is justified
when you are replacing parts.
. There is one screw (thread take-up lever
retaining screw) on the drop-feed type of sewing
machine that has a left-hand thread. It is found
#
in the face of the machine. This screw is removed
by turning it clockwise.
DISASSEMBLY
In this section we discuss the purpose of each
part of the 111 W 155 sewing machine and the
disassembly and reassembly of each part.
Before disassembling any sewing machine, you
should select and clean an area that will allow you
to work on your project with a minimum of
interruptions. Select your tools, cleaning solvents,
and a parts breakdown list; then you are ready
to begin your project.
Arm Cap
The arm cap (figure 4-2 [B]) permits inspection
of the mechanism of the arm. The arm mechanism
is exposed when the arm cap is moved to one side
or the other. Remove the arm cap by unscrewing
the holding screw and spring washer that attach
it to the machine arm; then lift the arm cap from
the machine.
Faceplate
The faceplate (figure 4-2 [F]) permits inspec-
tion and minor adjustment of the parts in the
machine face. The mechanism of the machine face
is exposed when the faceplate is moved to one side
or the other. Remove the faceplate by removing
the thumbscrew at the top of the plate; then move
the plate slightly to the left to clear the metal
projection at the lower left corner and lift the
faceplate from the machine.
Knee Lifter Lifting Lever Hinge Screw
The knee lifter lifting lever hinge screw (figure
4-11 [E]) acts as a hinging point for the knee lifter
lifting lever. It is removed from the machine by
unscrewing it.
Knee Lifter Lifting Lever
The knee lifter lifting lever (figure 4-11 [F])
acts as an extending arm that attaches the presser
bar lifting releasing lever bracket to the knee lifter
lifting lever. It carries the motion from the knee
lifter lifting lever to the presser bar lifting releasing
lever bracket. Remove the knee lifter lifting lever
by grasping and moving it outward from the
machine.
4-21
