Atlanta 4500A, Technical Manual & Parts Lists

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Technical Manual & Parts Lists
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d. Scooping amount of the looper
When the blade point of the looper has reached the center of needle, the standard distance
between the blade point and the upper end of the needle hole is 1.5 mm (1/16). When the No 2
carved line of the needle bar is matched with the lower edge of the needle bar lower bushing
Adjust that the blade point of the looper comes to the center of the needle. The returning amount
of the looper comes approximately 3.2 mm (1/8) and the relative relationship of the needle hole
and the thread hole of the looper becomes as show in the figure.
e. Clearance between the looper and the needle
The clearance between the looper and the needle, when the looper scoops up the thread, should
be as narrow as possible. After adjusting the needle guard, re-confirm this condition
f. The timing of the needle guard
The timing of the needle guard is determined by matching the
first screw of the figure with the flat part of the shaft.
g. Position of the needle guard
When the looper scoops up the needle thread; adjust so that
the needle point lightly touches the needle guard. Set the
height as high as possible to about cover the needle thread
loop. Loosen set screws (1) and (2) for this adjustment.
h. Thread spreader
Thread spreader is necessary in case of reverse sewing and at
the same time it is very important to obtain stable stitches
without skip-stitching in case of normal feed sewing.