S-7780A
6. STANDARD ADJUSTMENTS
56
6-6. Adjusting the needle and feed mechanism timing
1. urn on the power.
2. Turn off start backtack sewing, best PFM mode, slow start
and special locus.
3. Set the feed pitch to 4 mm.
4. Press and hold the ENTER key (1) and then press the
SEL key (2).
* The illustration at left shows the standard position for the
needle tip when the feed dog (3) is lowered from its highest
position until it is flush with the top of the needle plate (4).
5. Remove the side plate.
6. Loosen the two set screws (6) of the vertical cam (5), and
then turn the vertical cam (5) slightly to adjust the timing.
・
To advance the needle timing, turn in the direction of
<A>. To retard the needle timing, turn in the direction
of <B>.
・
To prevent material slippage from occurring, retard the
needle timing. (Fig. [B])
・
To improve thread tightening, advance the needle
timing. (Fig. [A])
NOTE:
If the vertical cam (5) is turned too far in the direction of
<A>, it may cause the needle to break.
7. After adjusting, securely tighten the set screw (6).
8. Install the side plate.
9. After adjusting, press the SEL key (2).
(Standard)
Needle timing is
advanced
Needle timing is
retarded
Approx. 1mm
1786D
