5-39. DARNING SEWING MACHINE TIMING.
This task consists of:
General Mechanics Tool Kit (Appendix B,
Machine removed from table (para. 2-18).
Thread, presser foot and needle guards
removed (para. 4-38).
Cylinder, needle plate and slide plate removed
(1) Make sure needle is correctly inserted into needle bar as far as possible. Rotate machine pulley
toward you, by hand, to ensure that needle goes to its lowest point.
(2) Time the machine by placing the needle at its lowest point and raising 2 mm (.08 in.) by rotating the
pulley toward you. Needle (1) and hook on the bobbin case (2) should be positioned so the hook is at
the top of the needle hole as shown.
(3) If the needle bar height is not correct, adjust needle bar accordingly.
Make sure gear teeth are meshed properly.
(4) If hook is not positioned properly, loosen screw on pinion. Rotate pinion and tightenscrew. Repeat
steps 2 through 4 until machine is properly timed.