SAFETY INSTRUCTIONS 1. Safety indications and their meanings This instruction manual and the indications and symbols that are used on the machine itself are provided in order to ensure safe operation of this machine and to prevent accidents and injury to yourself or other people. Indications The instructions which follow this term indicate situations where failure to follow the CAUTION...
CAUTION Sewing This sewing machine should only be used by Attach all safety devices before using the sewing operators who have received the necessary training machine. If the machine is used without these in safe use beforehand. devices attached, injury may result. Do not touch any of the moving parts or press any The sewing machine should not be used for any objects against the machine while sewing, as this...
4. INSTALLATION 4. INSTALLATION CAUTION t<::\ Use both hands to hold the machine head when Machine installation should only be carried out by a tilting it back or returning it to its original position. If qualified technician. only one hand is used, the weight of the machine Contact your Brother dealer or a qualified electrician head may cause your hand to slip, and your hand for �my electrical work that may need to be done.
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2481B 4. INSTALLATION 4-1. Installation 1. Oil pan (1) Head cushions (left) (2 pcs] (2) Head cushions (right) [2 pcs] (3) Oil pan (4) Oiler 2874M 2. Rubber cushions (1) Rubber cushions [2 pcs] (2) Nails [4 pcs] 3. Knee lifter complying bar (3) Knee lifter complying bar 4.
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4. INSTALLATION 5. Knee lifter plate (1) Knee lifter plate (2) Bolt ___ I) Loosen the bolt (3) and the bolt (4), and move the knee lifter plate (1) to a position where it is easy to use. 2961M <Knee lifter adjustment> 1.
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4. INSTALLATION 6. Ground wire (1) Ground wire (2) Screw Ground symbol Be sure to connect the accessory ground wire (1) to the motor. Align horizontally to the right and then tighten. (2)� 2964M 7. Ground wire (1) Ground wire Ground symbol ( 1) '.:::::=======:@o...
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12. Belt cove � D lid ( 1) Belt cover D hd • 2972M Pull belt cover 2 forward to adjust that there is n v�� D � between belt co and the e i Tt tover D lid (1 ). U (3 2973M Re-tighten the woo...
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4. INSTALLATION 13. Alarm display (semi dry type) (1) Alarm display (2) Screws (2 pcs] (Use for tightening rear cover) (3) Screws [4 pcs: removed] (4) Connector After connecting the connector ( 4) to Place the cord securely connector <CN1 > on the P.C.B. of the into the notch.
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2354B 2484B 4. INSTALLATION 4-2. Lubrication CAUTION Do not connect the power cord until lubrication has been completed, otherwise the machine may operate if the treadle is depressed by mistake, which could result in injury. Be sure to wear protective goggles and gloves when handling the lubricating oil and grease, so that they do not get into your eyes or onto your skin, otherwise inflammation can result.
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4. INSTALLATION ■ Lubrication Apply 1 - 2 drops of oil to the places indicated by the arrows. <Minimum lubrication type only> • Do not apply oil for semi dry types. i - - - -t- -=-= = c:::=:.. -----'- --..
4. INSTALLATlON 4-3. Checking the machine pulley rotating direction .A.CAUTION Do not touch any of the moving parts or press any objects against the machine while sewing, as this may result in personal injury or damage to the machine. 1. Insert the power cord plug into the wall outlet, and then turn on the power switch.
5. PREPARATION BEFORE SEWING 5. PREPARATION BEFORE SEWING 5-1. Installing the needle CAUTION Turn off the power switch before installing the needle. The motor will keep turning even after the power is switched off as a result of the motor's inertia. Wait until the motor sto p s fully before starting work. The machine may operate if the treadle is depressed by mistake , which could result in in j ury.
5. PREPARATION BEFORE SEWING 5-2. Removing the bobbin .A_CAUTION Turn off the power switch before removing the bobbin. The motor will keep turning even after the power is switched off as a result of the motor's inertia. Wait until the motor stops fully before starting work. The machine may operate if the treadle is depressed by mistake, which could result in injury.
5. PREPARATION BEFORE SEWING 5-3. Winding the lower thread A.CAUTION Do not touch any of the moving parts or press any objects against the machine while winding the lower thread, as this may result in personal injury or damage lo the machine. 1.
2488B 5. PREPARATION BEFORE SEWING 5-4. Installing the bobbin AcAur10N Turn the power switch before installing the bobbin. The motor will keep turning even after the power is switched off as a result of the motor's inertia. Wait until the motor stops fully before starting work. The machine may operate if the treadle is depressed by mistake, which could result in injury.
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5. PREPARATION BEFORE SEWING <Bobbin case type> 1. Insert the bobbin (1) into the bobbin case (2) so that the <A> 50mm winding direction is as shown in the illustration. 2. There are three types of cap (2) (<A>, <B> and <C>). Thread the thread by one of the following methods in accordance with the shape of the bobbin case (2) being used.
5. PREPARATION BEFORE SEWING 5-6. Adjusting the stitch length 1. Unlock the stitch length dial (2) by turning the dial lock lever (1) to the right until a click is heard. 2. Turn the stitch length dial (2) clockwise or counterclockwise so that the desired stitch length is at the uppermost position on the dial.
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Move the stop lever (1) to the "R" position. 5. PREPARATION BEFORE SEWING 5-8. Corner sewing method (T-8450C, 8750C) NOTE: If using this machine in place of a single-needle machine , remove the needle which is not being used. In such cases , do not use the procedures given below to stop the unused needle bar from moving , otherwise damage to the machine ma y result.
7. THREAD TENSION 7-2. Adjusting the presser foot pressure Correct stitches Upper thread 0894M Skipped stitches occur 0S95M Increase the pressure. Uneven stitch length 0S96M _______ __ s_ t s_ a _r_ e _p_ u _ c _ke I ____... Decrease the pressure.
7. THREAD TENSION 7-3. Adjusting the presser foot floating amount (minute lifting amount) When sewing stretch materials and materials with long 3096M pile, you can make minute adjustments to the floating amount for the presser foot (1) in accordance with the material.
2493B 2494B 8. CLEANING 8. CLEANING CAUTION Turn off the power switch before carrying out cleaning. The motor will keep turning even after the power is switched off as a result of the motor's inertia. Wait until the motor stops fully before starting work. The machine may operate if the treadle is depressed by mistake, which could result in injury.
8. CLEANING <Draining lubricating oil> 1. If the oiler (1) has filled with oil, unscrew the oiler (1 ) and dispose of the oil inside it. 2. Screw the oiler (1) back into the oil pan. 3002M 8-2. Lubricating via the oil cover (every 6 months) <Minimum lubrication type>...
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8. CLEANING <Applying grease> Use Brother-specified "Grease unit (SA8837-001)". 1. Using the tube 4087M 2. Applying grease Follow the procedure below to apply grease to the places indicated by arrows on the next page. , IIlillil ( 2 ) � L111 Tighten the screw (2) to push Insert the tip of the nozzle...
10. STANDARD ADJUSTMENT 10. STANDARD ADJUSTMENT CAUTION Turn off the power switch and disconnect the power Maintenance and inspection of the sewing machine fii:::. /2,... cord from the wall outlet at the following times. should only be carried out by a qualified technician. The motor will keep turning even after the power is Ask your Brother dealer or a qualified electrician to switched off as a result of the motor's inertia.
10. STANDARD ADJUSTMENT 10-3. Clearance between rotary hook and needle plate The clearance (A) between the rotary hook (1) and the needle plate (2) is adjusted as follows at the time of shipment from the factory. Model Distance (A) T-8420C T-8450C 0.9-1.2 m m T-8720C...
10. STANDARD ADJUSTMENT 10-4. Clearance between rotary hook and opener 1. Loosen the set screw (3) and move the opener (1) to the left or right to adjust so that the clearance between the rotary hook (2) and the opener (1) is 0.1-0.3 mm when the opener (1) is pulled as far as it will go in the direction of the arrow.
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10. STANDARD ADJUSTMENT 8. Loosen the screws (10), and then remove rotary hook base cover FL (11) and FR (12). (The screws (10) is designed so that they cannot be removed from the rotary hook base cover FL (11) and FR (12) to prevent them from being lost.) 9.
10. STANDARD ADJUSTMENT <For T-8450C and T-8750C> 13. Use an oil-based marker pen to color in the hollow of the needle. 14. With the needle raised, turn the machine pulley forward while pushing the needle against the rotary hook tip (15) with your finger to make a mark from the rotary hook tip (15) in the hollow of the needle.
10. STANDARD ADJUSTMENT 10-8. Feed dog position < Forward-back position adjustment> 3061M Carry out this adjustment if the needle and the needle hole in the feed dog are not positioned correctly even though the clearance between the needle bar and the presser bar (13.3-13.7 mm) is correct.
10. STANDARD ADJUSTMENT 10-10. Feed dog angle The standard angle for the feed dog is when the mark (2) on the feed bar shaft (1) is aligned with the reference line (4) on the feed rocker base arm (3). ( 1 ) ( 2 ) 1.
11. TROUBLESHOOTING Page Problem Possible cause Upper and lower threads Is the needle bent or is the needle tip broken? are breaking. Replace the needle if it is bent or broken. • Is the needle properly installed? If it is incorrect, install the needle correctly. •...
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