T-8421C, 8422C T-8452C, 8722C T-8752C Basic Operation Manual TWIN NEEDLE DIRECT DRIVE LOCK STITCHER Please read this manual before using the machine. Please keep this manual within easy reach for quick reference. This basic operation manual describes basic operations including sewing machine operations. For cleaning, standard adjustments and more details, please refer to the instruction manual contained in the Document CD.
Thank you very much for buying a BROTHER sewing machine. Before using your new machine, please read the safety instructions below and the explanations given in the instruction manual. With industrial sewing machines, it is normal to carry out work while positioned directly in front of moving parts such as the needle and thread take-up, and consequently there is always a danger of injury that can be caused by these parts.
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 DANGER The instructions which follow this term indicate situations where failure to follow the instructions may result in death or serious injury.
[2] Notes on safety DANGER Wait at least 5 minutes after turning off the power switch and disconnecting the power cord from the wall outlet before opening the cover of the control box. Touching areas where high voltages are present can result in severe injury. CAUTION Environmental requirements Use the sewing machine in an area which is free from sources of strong electrical noise such as electrical line noise or static electric noise.
CAUTION Sewing This sewing machine should only be used by operators who have received the necessary training in safe use beforehand. Attach all safety devices before using the sewing machine. If the machine is used without these devices attached, injury may result. The sewing machine should not be used for any applications other than sewing. 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.
[3] Warning labels The following warning labels appear on the sewing machine. Please follow the instructions on the labels at all times when using the machine. If the labels have been removed or are difficult to read, please contact your nearest Brother dealer. 1 2 Touching areas where high voltages are present can result in severe injury. Turn off the power before opening the cover.
Oil pan Control box Transformer box (100V/400V system only) 2166B 2506B Oil tank T-8421C, 8422C, 8452C, 8722C, 8752C v
CONTENTS 1. USEFUL FUNCTIONS FOR OPTIMUM SEWING................................................ 1 2. NAMES OF MAJOR PARTS ................ 2 6. SEWING ............................................... 29 6-1. Sewing ............................................................29 6-2. Backtacking.....................................................30 3. INSTALLATION .................................... 3 3-1. Table processing diagram .............................. 4 3-2. Installation ........................
1. USEFUL FUNCTIONS FOR OPTIMUM SEWING 1. USEFUL FUNCTIONS FOR OPTIMUM SEWING Thread take-up amount can be adjuste INSTRUCTION MANUAL CD 10-5. Adjusting the thread take-up amount Depending on the material and thread used, you can reduce the thread take-up amount to suit the material and thread being used by threading the thread through the thread amount adjuster (1). This can be useful if sewing with light material or if using slippery thread such as polyester thread.
2. NAMES OF MAJOR PARTS 2.
3. INSTALLATION 3. INSTALLATION CAUTION Machine installation should only be carried out by a qualified technician. Contact your Brother dealer or a qualified electrician for any electrical work that may need to be done. The sewing machine weighs more than 50 kg. The installation should be carried out by two or more people. Secure the table so that it will not move when tilting back the machine head. If the table moves, it may crush your feet or cause other injuries.
3. INSTALLATION 3-1. Table processing diagram The top of the table should be 40 mm in thickness and should be strong enough to hold the weight and with-stand the vibration of the sewing machine. Drill holes as indicated in the illustration below. Cotton stand hole Cord hole Head rest hole Control box mounting hole 2170B 3-2. Installation 1. Control box (1) (2) (3) (4) (5) Control box Bolts [3 pcs] Nuts [3 pcs] Spring washers [3 pcs] Washers [3 pcs] 2.
3. INSTALLATION 3. Oil pan (1) (2) (3) (4) Head cushions (left) [2 pcs] Head cushions (right) [2 pcs] Oil pan Oiler 2874M 4. Rubber cushions (1) Rubber cushions [2 pcs] (2) Nails [4 pcs] 5.
3. INSTALLATION 6. Machine head (1) Hinges [2 pcs] (2) Machine head (3) Head rest NOTE: Tap the head rest (3) securely into the table hole. If the head rest (3) is not pushed in as far as it will go, the machine head will not be sufficiently stable when it is tilted back. 2171B 7. Operation panel (1) Operation panel (2) Screws [2 pcs] (Use for tightening rear cover) 2172B 8.
3. INSTALLATION 9. Knee lifter plate (1) Knee lifter plate (2) Bolt * Loosen the bolt (3) and the bolt (4), and move the knee lifter plate (1) to a position where it is easy to use. 2173B 1. Turn the machine pulley so that the feed dog is below the top of the needle plate. 2. Lower the presser foot (5) by using the lifting lever (4). 2880M 2881M 3. Loosen the nut (6). 4.
3. INSTALLATION 3-3. 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.
3. INSTALLATION ■Lubrication Apply 1 - 2 drops of oil to the places indicated by the arrows. * Do not apply oil for semi dry types.
3. INSTALLATION 3-4. Connecting the cords DANGER Wait at least 5 minutes after turning off the power switch and disconnecting the power cord from the wall outlet before opening the face plate of the control box. Touching areas where high voltages are present can result in severe injury. CAUTION Contact your Brother dealer or a qualified electrician for any electrical work that may need to be done. Do not connect the power cord until all cords have been connected.
3. INSTALLATION (1) (2) (3) (4) (5) 6-pin head detector unit connector 12-pin operation panel connector 10-pin resolver connector 14-pin machine connector 4-pin motor connector Raise the tab (6). Lower the tab (6). Push in securely until the tabs (6) engage. 4139M 4140M 2. Binding the cords (1) Repeat cable tie NOTE: Bind the cords in such a way that the connector does not get pulled out.
3. INSTALLATION 3. Ground wire (1) (2) (3) (4) Ground wire Washer Spring washer Screw Oil pan Ground symbol Ground symbol 2176B 4. Other cords 4143M Connect cords that match the voltage specifications. < Europe specifications > (1) (2) (3) (4) Filter box Screws [4 pcs.] Staples [7 pcs.] Power cord 1. Attach an appropriate plug to the power cord (4). (The green and yellow wire is the ground wire.) 2. Insert the power plug into a properly-grounded electrical outlet.
3. INSTALLATION <200V system> (1) Power switch (2) Screws [2 pcs] Operator 4145M 2177B (3) 3-pin power supply connector (4) Power cord (5) Staples [5 pcs.] 1. Attach an appropriate plug to the power cord (4). (The green and yellow wire is the ground wire.) 2. Insert the power plug into a properly-grounded electrical outlet. NOTE: Take care when tapping in the staples (5) to make sure that they do not pierce the cords. Do not use extension cords, otherwise machine operation problems may result.
3. INSTALLATION <100V/400V system> (1) Power switch (2) Screws [2 pcs] Operator 4145M 2179B (3) (4) (5) (6) (7) (8) (9) Transformer box Transformer box plates [2 pcs.] Screw [with washer] 3-pin power supply connector Staples [6 pcs.] Cord clamps [2 pcs.] Power cord 1. Attach an appropriate plug to the power cord (9). (The green and yellow wire is the ground wire.) 2. Insert the power plug into a properly-grounded electrical outlet.
3. INSTALLATION 3-5. Test operation (Operating the treadle) 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. 2114M Press the ON power switch (1). The power indicator (2) will illuminate. 2182B 2207B 1. Check that the machine sews at low speed when the treadle (3) is gently pressed to position (B).
3. INSTALLATION 3-6. Adjusting the treadle operation 4259M If the machine starts running at low speed when your foot is simply resting on the treadle, or if the treadle pressure is felt to be too weak, adjust the position (a to c) at which the treadle spring (1) is hooked onto the treadle lever (2). * a is the weakest position, and it becomes gradually stronger at b, c and d respectively. 1.
4. PREPARATION BEFORE SEWING 4. PREPARATION BEFORE SEWING 4-1. Installing the needle CAUTION Turn off the power switch before installing the needle. The machine may operate if the treadle is depressed by mistake, which could result in injury. 1. Turn the machine pulley to move the needle bar to its highest position. 2. Loosen the screws (1). 3. Insert the needle (2) straight in as far as it will go so that the long groove is facing inward, and then securely tighten the screws (1).
4. PREPARATION BEFORE SEWING 4-2. Removing the bobbin CAUTION Turn off the power switch before removing the bobbin. The machine may operate if the treadle is depressed by mistake, which could result in injury. 1. Open the slide plates (1) by moving them to the right and left. 2. Pull the rotary hook latches (2) upward, and them remove the bobbins (3). 2463B 1. Open the slide plates (1) by moving them to the right and left. 2.
4. PREPARATION BEFORE SEWING 4-3. Winding the lower thread 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 to the machine. 1. Turn on the power switch. 2. Place the bobbin (1) onto the bobbin winder shaft (2). 3. Wind the thread several times around the bobbin (1) in the direction indicated by the arrow. * Check that the thread is not loose anywhere along the thread path. 4.
4. PREPARATION BEFORE SEWING 4-4. Installing the bobbin CAUTION Turn off the power switch before installing the bobbin. The machine may operate if the treadle is depressed by mistake, which could result in injury. 2898M 1. Insert the bobbin (1) into the rotary hook (2) so that the winding direction is as shown in the illustration. 2. Return the rotary hook latch (3) to its original position. 3. Turn the machine pulley to rotate the rotary hook (2) until the tension spring (4) is visible. 4.
4. PREPARATION BEFORE SEWING 1. Insert the bobbin (1) into the bobbin case (2) so that the winding direction is as shown in the illustration. 2. There are three types of cap (2) (, and ). Thread the thread by one of the following methods in accordance with the shape of the bobbin case (2) being used. 1) 2) 2902M Pass the thread through slot (3) and under the thread tension spring (4). Pass the thread through the thread hole (8) and pull out about 50 mm.
4. PREPARATION BEFORE SEWING 4-5. Threading the upper thread CAUTION Turn off the power switch before threading the upper thread. The machine may operate if the treadle is depressed by mistake, which could result in injury. ・ Turn the machine pulley and raise the thread take-up (1) before threading the upper thread. This will make threading easier and it will prevent the thread from coming out at the sewing start. ・ Thread the left-side thread first.
4. PREPARATION BEFORE SEWING Do not pass the thread through. Pass the thread through. (Refer to page 54 of the instruction manual CD) If the tension discs are opened as follows, the thread will become easier to thread. Press the tension release plate (2).
4. PREPARATION BEFORE SEWING 4-6. 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. The larger the number, the longer the stitch length will be. (The numbers on the dial are for use as a guide.
4. PREPARATION BEFORE SEWING 4-9. Corner sewing method (T-8452C, 8752C) 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 may result. 4-9-1. To stop the needle bars (right and left) Operate the stop lever after the needle has penetrated the material and has stopped moving.
5. USING THE G50 OPERATION PANEL (BASIC OPERATIONS) 5. USING THE G50 OPERATION PANEL (BASIC OPERATIONS) 5-1. Names and functions • The operation panel keys cannot be operated while sewing is in progress. Select the keys and set the number of stitches before starting sewing. • In the case of keys with indicators, the indicator illuminates when that function is operating, and the indicator switches off when the key is pressed once more.
5. USING THE G50 OPERATION PANEL (BASIC OPERATIONS) (7) Name label key When this key is pressed so that the indicator illuminates, fixed stitch sewing of the number of stitches (0-1999) in the E and F stitch number displays is carried out repeatedly. 4165M (8) Pleat presser sewing key When this key is pressed so that the indicator illuminates, the number of backtack stitches (0-1999) in the E stitch number display can be sewn by pressing the actuator switch.
5. USING THE G50 OPERATION PANEL (BASIC OPERATIONS) 5-2. Sewing start and end backtack stitches 2911M 1 Setting start backtack stitches For example, 3 stitches and 4 stitches 4175M 2 Setting end backtack stitches Example: 4176M 3 Start backtacking is carried out. After it has finished, normal sewing continues for as long as the treadle remains depressed.
6. SEWING 6. SEWING CAUTION Attach all safety devices before using the sewing machine. If the machine is used without these devices attached, injury may result. Turn off the power switch at the following times. The machine may operate if the treadle is depressed by mistake, which could result in injury.
6. SEWING 6-2. Backtacking 2916M When the actuator switch (1) or the reverse lever (2) is pressed during sewing, the feed direction will be reversed. When it is released, the feed direction will return to normal. 2917M < Actuator switch rotation function > The actuator switch can be rotated 90 degrees as shown in the illustration. Select the position (A or B) that is easier to use.
MEMO T-8421C, 8422C, 8452C, 8722C, 8752C
Document CD For cleaning, standard adjustments and more details, please refer to the instruction manual contained in the Document CD. 3168M Contents of the Document CD The following documents are contained in PDF format.
