Brother XM3700 Service Manual page 193

Adjustment
<From previous page>
11. Loosen the screw 1 of the BH change arm.
12. Move the position of the BH lever back and forth, and then loosen the screw 1 of the BH change arm.
*Key point
• Move the BH lever to the rear side. (direction "a")
→ The inside length of the stitch bar tack is shorter. (Fig. 2 "a")
• Move the BH lever to the front side. (direction "b")
→ The inside length of the stitch bar tack is longer. (Fig. 2 "b")
1
13. Execute the bar tack sewing again, and check the inside length of the stitch bar tack (the upper side and the
lower side).
14. Repeat the procedure 11 to 13 until length becomes the specified value.
BH lever
BH sewing length
Set Screw, Socket (FT)
M4X10
4 - 40
1
BH change arm
NG NG
e > 23 mm
OK
e = 22 1 mm (21-23 mm)
Fig. 2
e < 21 mm