Brother DB2-B721 User Manual

CONTENTS
1. NAMES OF MAJOR PARTS ..................... .
9. THREAD TENSION ...................................... 31
2. MACHINE SPECIFICATIONS..................... 3
9-1. Adjusting the thread tension .............. 31
9-2. Adjusting the presser foot
pressure ................................................ 32
3. OPTIONAL PARTS (B722/B724) .............. 5
9-3. Adjusting the trailing length after
thread trimming (8722/8724) ..............
32
4. WORK TABLE ............................................... 7
10.CLEANING ..................................................... 35
5. MOTOR (B721/B723) .................................. 8
11.STANDARD ADJUSTMENTS ................... 39
6. INSTALLATION ............................................. 9
11-1. Adjusting the thread tension
6-1. Installing the oil pan ............................ 10
6-2. Installing the machine head ............... 11
6-3. Installing the knee lifter assembly
(Except
-900) .. .......................... ...... ..... 12
spring .................................................... 40
11-2. Adjusting arm thread guideR ............ 42
11-3. Adjusting the presser foot height ...... 43
11-4. Adjusting the feed dog height ............ 44
6-4. Installing the belt ................................. 13
11-5. Adjusting the feed dog angle ............. 45
6-5. Installing the bobbin winder ............... 14
11-6. Adjusting the needle bar height ......... 46
6-6. Installing the belt cover ....................... 15
6-7. Installing the cotton stand .................. 18
6-8. Ground Wire Connections
(8721/8723) ...........................................
18
6-9. Lubrication ............................................ 19
6-10. Checking the machine pulley
rotating direction .................................. 20
11-7. Adjusting the needle and feed
mechanism timing ...............................
47
11-8. Adjusting the needle and rotary
hook timing ...........................................
49
11-9. Checking the rotary hook and 8-case
holder position bracket clearance ......
50
11-10.Adjusting the upper shaft and
rotary hook lubrication amount .........
51
7. PREPARATION BEFORE SEWING ........... 21
11-11.Adjusting the synchronizer
(8722/8724) ...........................................
52
7-1. Installing the needle ............................ 21
7-2. Removing the bobbin case ................. 22
12.REPLACING THE FIXED KNIFE AND
7-3. Winding the lower thread ................... 23
MOVABLE KNIFE (B722/B724) ................ 54
7-4. Installing the bobbin case ................... 25
12-1. Replacing the fixed knife ..................... 54
7-5. Threading the upper thread ................ 26
12-2. Replacing the movable knife .............. 55
7-6. Adjusting the stitch length .................. 27
7-7. Using the thread wiper
13.TROUBLESHOOTING ................................. 56
(8722/8724-400, 900, option) ........... 28
8. SEWING ......................................................... 29
8-1. Sewing .................................................. 30
8-2. 8acktacking ........................................... 30
082-8720 series (English)
From the library of: Superior Sewing Machine & Supply LLC

Brother DB2-B721 Specifications

General

Brand	Brother
Model	DB2-B721
Category	Sewing Machine
Language	English