– 37 –
Adjustment Procedures
Results of Improper Adjustment
™
Longitudinal direction
1. Loosen setscrews
1
and remove clamp spring base
2
.
2. Loosen setscrews
4
and adjust so that the distance from the
end of clamp spring base
2
to the top end of clamp spring
3
is 24.3
±
0.1 mm.
3. Assemble again clamp spring base
2
to the thread trimmer
base and tighten setscrews
1
so that clamp spring base
2
comes in close contact with the end of the thread trimmer base.
Confirmation : Check that the distance from the top end of
clamp spring
3
to the end of the machine bed is 28.3
±
0.2
mm.
™
Clamp pressure
1. Loosen setscrews
1
.
2. Move clamp spring base
2
in the direction of the arrow by
approximately 0.5 mm from the state that clamp spring
3
comes in contact with moving knife
5
. (Clamp spring base
2
should come in close contact with the end of the thread trimmer
base.)
3. Tighten setscrews
1
.
When the clamp spring is located
in the front :
™
Clamp spring interferes with the
moving knife to cause the spring
and the knife to break.
When the clamp spring is located
in the rear :
™
Defective clamp will result.
When the clamp pressure is
excessively low :
™
Stitch skipping at the start of
sewing will result.
When the clamp pressure is
excessively high :
™
“Puckering” may be produced on
cloth at the start of sewing.
™
Moving knife interferes with the
clamp spring to cause them to
break.
