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Adjustment Procedures
Results of Improper Adjustment
Method of needle array check
1. Checks on the needle array parallelism are carried out after the
completion of needle bar height adjustments.
2. When checking the needle array parallelism, the needle bar
is
lowered to the midpoint under the condition that no looper is attached.
3. Make Line A of the upper knife
come in contact with the left needle
and the retainer needle
on both sides. In this state, check the
parallelism between Line B of the upper knife
and Line C of the
throat plate groove.
4. If no parallelism is secured, insert a spanner (7mm/9/32) in the needle
clamp
and try to secure the needle array parallelism by turning
the needle bar
to the right and left.
(Caution) If checking is intended without the dislodgment of the
looper, do it in the position where the left needle
and
the retainer needle
do not come in contact with the
rear side of the looper.
5. After the confirmation of parallelism, check the needle bar height
again and fix the needle bar connecting bracket setscrew
.
When the needle parallelism is not
secured
o This will be a cause of stitch skip-
ping, needle breakage, thread
breakage, or destruction of throat
plate claws.
From the library of Superior Sewing Machine & Supply LLC - www.supsew.com
