1. Setting the belt ..................................................................................................................................... 3

2. Installing the thread stand .................................................................................................................. 4

3. Installing the belt cover, the bobbin winder base and the bobbinwinder ...................................... 5

4. Installing the hemming binder ............................................................................................................ 6

5. Applycation of grease ......................................................................................................................... 7

#. INSTALLATION (DLN-6390-7)....................................................................................... 8

1. Installing and settIng of SC-921 ......................................................................................................... 8

2. Wiring the cords .................................................................................................................................. 9

3. Installing the knee switch ................................................................................................................. 10

4. Piping pneumatic components and wiring electric components ................................................. 11

$. INSTALLATION (DLN-6390) ........................................................................................ 12

1. Selecting the motor pulley and the belt ........................................................................................... 12

2. Installing the motor ........................................................................................................................... 13

3. Set-up of the hemming binder open/close mechanism ................................................................. 14

4. Set-up of the presser foot lifting mechanism ................................................................................. 15

5. Simultaneous operation of the presser foot lifting and open/close of the hemming binder ..... 16

%. LUBRICATION AND DRAINING .................................................................................. 17

1. Lubrication ......................................................................................................................................... 17

2. Draining .............................................................................................................................................. 18

3. Adjusting the amount of oil .............................................................................................................. 19

^. OPERATION ................................................................................................................ 21

1. Attaching the needle ......................................................................................................................... 21

2. Setting the bobbin into the bobbin case ......................................................................................... 21

3. Threading the machine head ............................................................................................................ 22

4. Adjusting the stitch length ............................................................................................................... 23

5. Winding the bobbin thread ............................................................................................................... 24

6. Thread tension ................................................................................................................................... 25

7. Theead take-up spring ...................................................................................................................... 25

8. Adjusting the thread take-up stroke ................................................................................................ 25

&. ADJUSTING THE SEWING MACHINE ....................................................................... 26

1. Adjusting the height of the needle bar ............................................................................................ 26

2. Installing position of the hook .......................................................................................................... 27

3. Adjusting the needle stop position .................................................................................................. 28

4. Explanation and adjustment of the pedal components ................................................................. 29

5. Adjusting the wiper ........................................................................................................................... 30

6. Hand lifter ........................................................................................................................................... 31

7. Adjusting the presser foot pressure (upper feed roller) and

the height of the presser foot (upper feed roller) ........................................................................... 31

8. Adjusting the presser foot pressure (presser foot (asm.)) and

the height of the presser foot (presser foot (asm.)) ....................................................................... 32

*. TROUBLES IN SEWING AND CORRECTIVE MEASURES ....................................... 33

(. THREAD TRIMMER COMPONENTS .......................................................................... 36

1. Checking the receding position of the moving knife and the correcting method ....................... 36

2. Checking the thread trimmer cam timing ........................................................................................ 37

3. Counter knife ...................................................................................................................................... 38

). SETUP OF OPTIONAL COMPONENTS ..................................................................... 39

1. Needle cooler ..................................................................................................................................... 39

_. SETTING OF SC-921 ................................................................................................... 44

1. Setting of the auto lifter function ..................................................................................................... 44

CONTENTS

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Table des Matières