Thread For Safety Stitching; 4-22-8.Adjusting The Amount To Pull The Gimp - Brother RH-981A Service Manual

4-22-7. Adjusting the amount to pull the lower thread for safety stitching
To secure the first stitch, while looper L is catching the first upper loop, the lower thread should be taut between
looper L and the throat plate, and not be pulled off thread clamp D.
1. After automatic sewing is completed, switch to the MANUAL mode, and press the start switch.
2. Turn the pulley manually to check the condition of the lower thread.
To prevent the lower thread from being pulled off thread clamp D while the feed bracket is moving to the sewing start
position, the pressure of thread clamp D should be sufficiently strong enough, and the tension release lever (1)
should be oscillated by the tension release claw (2) to pull the lower thread appropriately while the looper base
returns to the home position after thread trimming is completed.
When the stitch length is greatly changed, it is necessary to adjust the amount of lower thread to be pulled.
4-22-8. Adjusting the amount to pull the gimp
1. Turn off the power.
2. Turn the looper base (3) manually to check the angle
of the tension release lever (1).
3. Loosen the screw (4), turn the tension release claw
(5) regarding the pivot (6) as the center to adjust the
angle of the tension release lever (1).
Note: When the tension release lever (1) oscillates
with its maximum stroke, make sure that it
does not make contact with the looper link
(7).
3811Q
The amount of the gimp required for thread trimming is
pulled by the thread trimmer that cuts the lower thread
and the gimp, leaving them longer.
If adjustment is not correct, the gimp sewn in stitches
may be pulled, and stitch formation around the button
eyelet may be distorted.
Loosen the two screws (1), and set the distance from
the bed to the upper end of the roller to 11 mm.
3812Q
RH-981A
4. ADJUSTMENT
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