9. STANDARD ADJUSTMENTS
9-3. Adjusting the loop stroke
The loop stroke is the distance the needle bar rises from its lowest position to the position where the tips of the eye looper and right looper are aligned with the center of the needle. The standard loop stroke is 2.7 mm. (The loop stroke may need changing depending on the material and thread being used.)
* Carry out the adjustment in
2.7 mm
3079Q
1.In the same way as in
2.Add 2.7 mm to the value obtained in step 1. above.
3.Touch the end of the calipers (A) against the top of holder base (2), and then turn the upper shaft pulley until the end of the needle bar (1) touches the edge of the calipers (B). Check that the tip of the eye looper is aligned with the center of the needle at this time.
4.In the same way, check that the tip of the right looper is aligned with the center of the needle when the needle is at the outside sewing position.
3080Q | 3081Q |
5.If the tips of the loopers are not aligned with the center of the needle, carry out the adjustment below. Raise the machine head.
Loosen the two screws (3) of the lower shaft timing pulley, hold the upper shaft pulley so that it doesn't move, and then turn the lower shaft cam (4) in the direction indicated by the arrow until the tip of the eye looper (5) is aligned with the center of the needle (6). Once they are aligned, tighten the two screws (3).
After adjusting, check that the screws have been adequately tightened.
Once this adjustment has been carried out, repeat the procedure given in
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