BROTHER SL-7 (01) PDF Document

The symbols used in the service manual indicate the following actions:

• An arrow pointing up or down: Move the part in the direction of the arrow.

• Two opposing vertical arrows with a line between them: Set the clearance as indicated.

• An arrow pointing up and an arrow pointing down, each with a line at its base: Move the part to its highest or lowest position.

The update record table contains the following information:

A record dated 1.2011 notes the addition of models LS-3000 and LS5000, with no specific contents mentioned.

To remove the covers, please follow these steps:

1. Remove the accessory table.

2. Loosen and remove the screw, then remove the face plate.

3. Loosen and remove the screws, then remove the front cover.

4. Loosen and remove the screws, lower the presser foot lifter, then remove the rear cover.

The standard clearance between the needle and the shuttle hook point should be 0.02 to 0.1mm. The shuttle race should also be positioned correctly with respect to its turning direction. To adjust this on your BROTHER SL-7:

1. Set the pattern selection dial to 6.

2. Turn the balance wheel to set the needle and the shuttle hook to the correct timing position.

3. Turn the needle bar supporter stud slightly to either the right or left to adjust the clearance between the needle and the shuttle hook.

Note: The center of the needle should align with the center of the shuttle hook shaft.

The shuttle driver should rotate smoothly with no play felt in the race way. To adjust the clearance on your BROTHER SL-7:

1. Loosen the setscrews of the driver shaft gear.

2. Adjust the clearance of the driver shaft.

3. Retighten the setscrews.

For the BROTHER SL-7, when the pattern selection dial is set at 4 (Zigzag), the needle swing should be 0.05 mm or less as the needle moves down from the needle plate to its lowest position. While the needle moves up from its lowest position to the needle plate, the needle swing should be 0.15 mm or less. These clearances should be on both sides of the needle plate hole.

To adjust:

1. Set the pattern selection dial to 4 (Zigzag).

2. Loosen the three set screws on the worm gear.

3. Turn the worm gear to adjust the needle swing.

4. Tighten the three set screws on the worm gear.

Note: Make sure that the biting worm gear aligns with the pattern cam gear.

When the pattern selection dial on your BROTHER SL-7 is set at 4 (Zigzag), the needle should move within a range of 5.0 to 5.4 mm across the needle plate. When the needle is lowered, it should not be too close to either the left or right edge of the needle plate hole. To adjust:

1. Set the pattern selection dial to 4.

2. Turn the balance wheel to lower the needle until it is just above the needle plate.

3. Loosen the locknut for the adjusting screw on the zigzag connecting rod.

4. Using a screwdriver, turn the screw and adjust the needle movement range with respect to the needle plate hole.

5. Tighten the locknut.

The standard for the BROTHER SL-7 is that when the pattern selection dial is set at 4 (Zigzag) and the needle is raised 1.7 to 2.1 mm from its lowest position on the left side, the shuttle hook point should align with the side of the needle. To adjust:

1. Set the pattern selection dial to 4 (Zigzag), then lower the needle to its lowest position at the left side of the needle plate.

2. Loosen the set screw on the drive connecting rod.

3. Raise the needle between 1.7 and 2.1 mm and align the shuttle hook point with the side of the needle.

4. Tighten the set screw.

When the pattern selection dial is set at 4 (Zigzag), and the needle is on the right side and contacts the shuttle hook, the clearance between the top of the needle eye and shuttle hook point should be within 0.8 and 1.2 mm. To adjust the needle bar height on your BROTHER SL-7:

1. Set the pattern selection dial to 4 (Zigzag), then lower the needle to its lowest position at the right side of the needle plate.

2. Turn the balance wheel until the needle contacts the shuttle hook.

3. Loosen the set screw on the needle bar.

4. Move the needle bar either up or down until the clearance between the top of the needle eye and the shuttle hook point is within 0.8 and 1.2 mm.

5. Tighten the set screw.

The timing belt on your BROTHER SL-7 should slacken approximately 4 – 6mm under a 2N (200g) load. To make an adjustment:

1. Loosen the setscrews on the motor holder for 220/240V models.

2. Loosen the nuts on the motor holder for 120V models.

3. Move the motor to make the adjustment.

4. Retighten the setscrews and nuts.

The feed dog teeth on your BROTHER SL-7 should be 0.9 – 1.1mm above the needle plate at their highest position. To adjust:

1. Loosen the setscrew on the vertical feed arm.

2. Loosen the fixation screw of the eccentric nut.

3. Turn the eccentric nut to make the adjustment.

4. Retighten the fixation screw of the eccentric nut.

5. Retighten the setscrew.

The clearance between the presser foot and the needle plate on the BROTHER SL-7 should be between 6.0 and 6.5mm. To adjust the height:

1. Raise the presser foot.

2. Loosen the screw on the presser bar guide bracket.

3. Adjust the height of the presser bar.

4. Tighten the screw.

Note: Check that the presser foot and feed dogs are aligned.

When a buttonhole is sewn using the b, ac, and d settings on the pattern selection dial, the left backward stitching and right forward stitching should appear identical. To adjust this on your BROTHER SL-7:

1. Set the buttonhole adjustment dial to 0°.

2. Set the pattern selection dial to ‘b’ and sew the left side of the buttonhole.

3. Loosen the screw on the reverse sewing regulator shaft.

4. Using a screwdriver, turn the reverse sewing regulator shaft to adjust the left backward stitching (b) until it feeds 35 to 45 stitches/20 mm.

5. Tighten the screw.

6. Set the pattern selection dial to ‘d’ and sew the right side of the buttonhole. Caution: Satin stitch 4 will change according to the pitch length adjustment of the left backward stitching.

7. Loosen the fixation screw of the eccentric nut.

8. Use the nut to make adjustments so that the length of the right forward stitching is the same as the left backward stitching.

9. Tighten the screw.

The width of the buttonhole’s right forward stitching should appear identical to that of the left backward stitching (the difference should be less than 0.2 mm). To adjust the width on your BROTHER SL-7:

1. Install the darning plate onto the needle plate and lower the presser foot onto a piece of paper.

2. Set the pattern selection dial to ‘b’.

3. Turn the balance wheel until the needle contacts the paper.

4. Set the pattern selection dial to ‘d’.

5. Turn the balance wheel until the needle contacts the paper.

6. Using a screwdriver, turn the adjusting screw to change the stitch width of the right side.

Note: Turn the adjusting screw to the right to make the stitch width of the right side more narrow.

A thread tension amount between 0.05 and 0.1N (5 and 10g) should be measured at dial position 0. To adjust the upper tension on your BROTHER SL-7:

1. Remove the tension dial sheet and the stop ring.

2. Remove the tension dial.

3. Turn the adjusting nut left or right to make the adjustment.

4. Remount the tension dial at the zero position then the stop ring and the tension dial sheet.

Note: Cotton thread #50 should be used when adjusting the tension. Do not include take up spring torque.

The bobbin on your BROTHER SL-7 should be wound evenly, up to 75-85% of its outer diameter. To adjust the winding:

1. Loosen the set screw of the pretension slightly.

2. Shift the pretension up or down until even winding is achieved.

3. Retighten the set screw.

4. Loosen the set screw of the bobbin presser.

5. Adjust the bobbin presser until the correct amount of thread is wound.

6. Retighten the set screw.

The standard lower thread tension for the BROTHER SL-7 is 0.3 – 0.35N (30 – 35g). To check and adjust the tension:

1. Set cotton thread #50 in the bobbin case and pull it with a tension gauge slowly.

2. Adjust the adjustment screw to a tension of 0.3 – 0.35N (30 – 35g).