typical GT1790A - Machine Maintenance Procedures; Needle-to-Hook Relation Adjustment

-
66
-
VI. Maintenance
1. Adjusting the needle-to-hook relation
! Warning
Please turn off the power switch and confirm that the motor has stopped before operation to
prevent personal injuries caused by unexpected start.
Adjust the needle-to-hook relation when the needle
enters the center of the needle hole in the throat plate.
(1) Needle bar height
1) Drop the needle bar to the lowest point.
2) Insert part [1] A of timing gauge into the gap
between the bottom end of needle bar and throat
plate, where the needle bar touches the timing
gauge as shown in the figure.
3) Loosen needle bar connection screw ①, and adjust
the height of the needle bar.