7. STANDARD ADJUSTMENTS

7-5. Adjusting the needle bar height

Reference line (a), which is the second line from the bottom of the needle bar (1) (fourth line from the bottom when using a DA x 1 needle) should be aligned with the lower edge of the needle bar bush D (2) as shown in the illustration when the needle bar (1) is at its lowest position.

1. Turn the machine pulley to set the needle bar (1) to its lowest position.

2. Remove the oil cap (3).

3. Loosen the screw (4) and then move the needle bar (1) up or down to adjust its position.

4. Securely tighten the screw (4).

5. Replace the oil cap (3).

0535D

7-6. Adjusting the needle and feed mechanism timing

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The illustration at left shows the standard position for the needle tip when the feed dog (1) is lowered from its highest position until it is flush with the top of the needle plate (2).

Approx. 1 mm

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Approx. 3 mm

Flush with top of needle plate

Needle timing is

(Standard)

Needle timing

advanced

 

is retarded

 

 

0536D

1.Remove the rubber cap (3).

2.Loosen the two set screws (5) of the vertical cam (4), and then turn the vertical cam (4) 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 (4) is turned too far in the direction of <A>, it may cause the needle to break.

3.After adjusting, securely tighten the set screw (5).

4.Replace the rubber cap (3).

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S-7000DD