− 27 −
(3) Skip of stitches
1) Readjust and coordinate the needle and looper timing.
2) For stitching heavy-weight or hard materials, the needle guide should touch the needle by 0.1 to 0.2 mm as
shown in the figure.
(4) Thread slippage from the needle
(Thread slips from the needle, and stitches are not formed from the beginning.)
1) Increase the travel of the thread pull-off lever.
2) The clearance between the thread nipper and the nipper block is too large.
™ Correct the clearance to 0.8 to 1.2 mm. (In case of MB-377, 0.5 to 0.8 mm)
3) Prevent skipped stitches.
4) Decrease the tension of the thread tension No. 3 of the front cover. (In case of MB-377)
(5) Excessive remaining thread
Excessive remaining thread (needle thread)
(The end of thread of a beginning stitch is left on the top of a button.)
1) The end of thread comes out from “A” hole.
™ Decrease the travel of the thread pull-off lever.
2) The end of thread comes out from “B” hole.
™ Increase the travel of the thread pull-off lever.
Excessive remaining thread (looper thread)
(The end of thread of a beginning stitch is left on the wrong side of a fabric.)
1) Decrease the travel of the thread pull-off lever.
2) The end of thread of a beginning stitch comes out from a point different from the point where the needle
enters when observing the wrong side of a fabric.
™ Increase the work pressing force.
0.1 to 0.2 mm
A
B
To Next Page
Need help?
General
