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 lever, and consequently there is always a danger of injury that can be caused by these parts.
Furthermore, do not excessively bend the cords or secure them too firmly Contact your Brother dealer or a qualified electrician with staples, otherwise there is the danger that fire or for any electrical work that may need to be done.
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. Hazardous voltage Hochspannung Un voltage non adapté...
CONTENTS 1. NAME OF EACH PART 5. OPERATION ........1 ............28 5-1. Part names and functions........28 2. SPECIFICATIONS ..........2 5-2. Home position return (preparation).....30 2-1. Subclass ..............2 5-3. Operating the treadle ...........31 2-2. Specifications ............2 5-3-1. Operating the standing pedal (option) ..32 2-3.
10. STANDARD ADJUSTMENTS ......71 10-1. Needle bar height..........71 10-2. Needle and hook timing adjustment ....72 10-3. Adjusting the clearance between needle and hook point ..............72 10-4. Adjusting the inner rotary hook and rotary hook holder overlap............73 10-5. Adjusting the work clamp pressure.....73 10-6.
1. NAME OF EACH PART 1. NAME OF EACH PART (12) (11) (10) (14) (13) (15) (16) 2034Q (1) Power switch (2) Control box (3) Operation panel (4) Treadle (5) AC servo motor (6) Emergency stop switch (7) Spool stand (8) Pulley (9) Tension release lever Safety devices...
2. SPECIFICATIONS 2. SPECIFICATIONS 2-1. Subclass Subclass Subclass Subclass Buttonholes for Buttonholes for clothing such Buttonholes for Main use knitted garments such as as work clothes and women’s clothing such as dress knitted underwear, sweaters, clothes shirts, blouses, work clothes cardigans and jerseys Belt holes for child seats, etc.
3. OPTIONAL PARTS 3. OPTIONAL PARTS 3-1. Special needle plate This needle plate uses the elasticity of rubber to prevent the cutter from getting stuck and not returning. It also helps to keep the cutter blade sharp. Parts name Parts code Needle plate set 1.2RB S51361-001 General...
3. OPTIONAL PARTS 3-7. Replacement parts set (for 70 mm buttonhole length) Replacement parts set –70 S54501-001 2046Q 3-8. Programmer You can use the icon keys to retrieve parameters at a single touch, and to display them as icons on the LED screen so that the settings can be changed easily.
Further- more, do not excessively bend the cords or Contact your Brother dealer or a qualified secure them too firmly with staples, other- electrician for any electrical work that may wise there is the danger that fire or electric need to be done.
4. INSTALLATION 4-2. Installing the motor Install the motor (1) with the three bolts (2), flat washers (3), spring washers (4) and nuts (5). 2050Q 4-3. Installing the flange nut Install the four flange nuts (1) to the underside of the work table.
4. INSTALLATION 4-4. Installing the control box 2 mm 2052Q 1. Remove the 12 screws (1), and then open the covers (main P.C. board mounting plate (2) and sub P.C. mounting plate (3)). NOTE: When opening the cover, hold it securely so that it does not fall down. 2.
4. INSTALLATION 4-5. Installing the power switch 1. Install the power switch (1) with the two screws (2). 2. Secure the power switch (1) cord and the motor (4) cord with the six staples (3). 2053Q 4-6. Installing the bed base 1.
4. INSTALLATION 4-7. Installing the machine head NOTE: 2055Q The bed base (1) is made from plastic, so be careful not to hit it with the machine head when placing the machine head on top of it. 1. Open the hinges (2) as shown in the illustration. Then place the machine head gently on top of the bed base (1), while being careful not to clamp the cords (3).
4. INSTALLATION 4-9. Installing the operation panel The operation panel can be installed to either the top 2057Q Top of work table Top of work table or bottom of the work table. 1. Install the rear frame (1) to the work table (top or bottom) with the four wood screws (2).
4. INSTALLATION 4-11. Connecting the cords CAUTION Be sure to connect the ground. If the ground connection is not secure, you run a high risk of receiving a serious electric shock, and problems with correct operation may also occur. NOTE: The harness is connected in the same way regardless of whether the machine head is positioned horizontally or vertically.
4. INSTALLATION 4-11-3. Connecting the motor harness 1. Pass the motor harness (1) through the rubber cushion (2). 2. Connect the connectors (3). 3. Secure the motor harness (1) with staples. 2063Q 4. Connect the connectors of the feed motor harness (4) and the presser foot motor harness (5).
4. INSTALLATION 6. Connect the connectors of the synchronizer harness (11), the home position sensor harness (12) and the emergency stop switch harness (13). Main P.C.board Harness Mark (13) indication (12) (11) Synchronizer<5-pin> P3<SYNC> Home position sensor (12) P11<ORG> <12-pin> (13) Emergency stop<11-pin>...
4. INSTALLATION 4-11-5. Connecting the standing pedal harness (option) 1. Pass the marked tube of the relay harness (1) into the control box through the hole (2) in the control box. 2. Connect the relay harness (1) to connector P9 on the main circuit board (3).
4. INSTALLATION 4-11-6. Installing the transformer The transformer can be installed on the floor, on the work table leg (on top of the leg or on the treadle support plates) or underneath the work table. * Check the power supply rating label on the transformer to confirm that the voltage ratings for the transformer and the control box are identical.
4. INSTALLATION 4) Installation underneath the work table 2075Q Work table hole * Standard BROTHER work tables are provided positions with installation holes for use in installing the transformer. 1. Remove the screws (1), and then remove the handle (2).
4. INSTALLATION 4-12. Installing the V-belt 1. Remove the screw (1), and then remove the motor belt cover (2). 2081Q 2. Gently tilt back the machine head, and then place 2082Q the V-belt (3) into the V grooves in the machine head pulley and the motor pulley.
4. INSTALLATION Adjusting the belt retainer 1. Loosen the screw (1). 2. Align the boss of the belt retainer (2) with the mark (3). 3. Tighten the screw (1). Tighten the screw (1). Adjusting the finger protector 1. Loosen the screw (4). 2.
4. INSTALLATION 4-14. Installing the treadle Install the connecting rod (1) to the treadle lever (2) with the nut (3). 2087Q Adjusting the treadle pressure If the machine starts running when your foot is simply resting on the treadle, or if the treadle pressure is too weak, adjust the position (a to c) at Fig.
4. INSTALLATION 4-14-1.Changing the treadle unit installation position (horizontal positioning only) NOTE: If the machine head is positioned horizontally, install the treadle unit to the motor. 1. Disconnect the treadle unit connector (1) inside 2089Q the control box. 2. Remove the screw (2), and then disconnect the ground wire.
4. INSTALLATION 4-16. Installing the eye guard CAUTION Attach all safety devices before using the sewing machine. If the machine is used without these devices attached, injury may result. (2)(3) [Vertical positioning] [Horizontal positioning] 2093Q 2092Q Install the eye guard (1) with the screw (2) and flat washer (3). NOTE: If the machine head is positioned horizontally, install the eye guard support (4) to the machine head with the screw (5), and then install the eye guard (1).
Keep the oil out of the reach of children. NOTE: Be sure to let the machine operate for a while after adding the oil. Use only specified Brother oil (Nisseki Mitsubishi Sewing Lube 10N; VG10) for the machine oil. 4-17-1. Lubricating the bed base 2094Q 1.
4. INSTALLATION 4-17-2. Lubricating the arm NOTE: * Be sure to lubricate the arm when first installing the machine and when the machine has not been used for an extended period of time. * When using the machine, check that the oil is visible through the oil cap (2). If it cannot be seen, problems such as seizure of the mechanism may occur.
4. INSTALLATION 4-18. Installing the belt cover 2098Q 1. Attach the rubber cap (2) to the belt cover (1). 2. Insert the belt cover (1) in the direction of the arrow, and then secure it with the two screws (3), the screw (4) and the flat washer (5).
5. OPERATION 5. OPERATION 5-1. Part names and functions (1) POWER indicator (2) Warning indicator (3) RESET key (4) Cutter on indicator (5) CUTTER ON key (6) Program number LED (10) (7) Program No. UP key (14) (11) (8) Program No. DOWN key (9) Automatic mode indicator (12) (15)
5. OPERATION (10) Test feed mode indicator • Illuminates during test feed mode. This mode is used to check the number of stitches in the sewing pattern. (11) Manual mode indicator • Illuminates during manual mode. In this mode, a single stitch is sewn each time the machine pulley is turned manually.
5. OPERATION 5-2. Home position return (preparation) Before starting home position return..Check that the needle bar is at its highest position. Turn the machine pulley so that the index mark (18) on the pulley is between the marks (19) on the belt (18) cover.
5. OPERATION 5-3. Operating the treadle 1. When the treadle is not depressed [A], the work 2103Q 2104Q clamp is at the neutral position. * The work clamp lifter height at the neutral position can be changed to between 1 mm and 13 mm using memory switch No.
5. OPERATION 5-3-1. Operating the standing pedal (option) [Two pedals + kick pedal] When the work clamp pedal (right side) is depressed, the work clamp is lowered, and when the start pedal (left side) is depressed, sewing starts. When the kick pedal is kicked to the outside, the work clamp rises.
5. OPERATION 5-4. Program setting method 5-4-1. Program initialization condition The parameters and memory switches for program numbers 1 to 90 are all set to their default values. 5-4-2. Parameter table • The parameter values can be stored independently for each program. •...
5. OPERATION Setting items Setting range Unit Default Zigzag width 1.0 - 3.0 mm 1441Q Knife X space – 0.4 - 1.0 mm 1442Q Knife Y space 0.00 - 2.00 mm 0.05 1.00 1443Q Knife X position alignment – 0.5 - 0.5 mm 1444Q Knife Y position alignment –...
5. OPERATION Setting items Setting range Unit Default Straight bar tack length 7.0 - 40.0 mm 13.0 1448Q Straight bar tack pitch 0.2 - 2.0 mm 1449Q Straight bar tack width 1.5 - 6.0 mm 1450Q Running speed 1,000 - 3,000 rpm 2,000 Running length 3.0 - 32.0 mm...
5. OPERATION Setting items Setting range Unit Default Front tack pattern 0: Rectangle 1: Radial 2: Round 3: Tack 4: Taper tack Radial Round Tack Taper Rectangle tack Front tack length (except taper tack) 0.5 - 5.0 mm 1454Q Front tack pitch (except radial) 0.05 - 1.00 mm 0.05 0.30...
5. OPERATION Setting items Setting range Unit Default Rear tack sideways correction (rectangle only) – 1.0 - 1.0 mm 1465Q Rear tack vector shape (rectangle only) 1. Triangle 2. Rectangle 3. Saw-shape 1466Q No. of stitches in X direction for saw-shaped rear 2 - 14 stitches tack vector shape (When sewing saw-shaped rear tack stitches for rectangular buttonholes)
5. OPERATION Setting items Setting range Unit Default Start backtack 0 - 6 stitches 1469Q Start backtack width 0.5 - 3.0 mm 1470Q Start backtack pitch 0.10 - 0.80 mm 0.05 0.30 1471Q End backtack 1- 6 stitches 1472Q Cutter operation 0: Center knife (standard) 1: Rear knife (feeding) 2: Front knife...
5. OPERATION Setting items Setting range Unit Default No. of underlays sewn together 0 - 1 1474Q Saw-shaped underlays 0: No saw-shaped underlay 1: Front and rear tack 2: Rear tack only 3: Front tack only 1475Q No. of rectangle underlays 0 - 9 1476Q Underlay speed...
5. OPERATION Setting items Setting range Unit Default Underlay sewing start pitch 0.2 - 2.0 mm 1480Q Saw-shaped underlay bar tack X stitch no. 2 - 14 stitches 1481Q Saw-shaped underlay bar tack Y stitch no. 1 - 5 stitches 1482Q 2-cycle sewing 0: No double stitch...
5. OPERATION Setting items Setting range Unit Default Sewing start tension apply timing – 4 - 6 stitches 1486Q Rear bar tack tension release timing – 4 - 4 stitches 1487Q Rear bar tack tension apply timing – 4 - 4 stitches 1488Q Front bar tack tension release timing –...
5. OPERATION 5-4-3. Changing program details Example 1: This example shows how to make a buttonhole (round) setting for program number 3. 1. Press the SELECT key (13) to change the mode to automatic, test feed or manual mode. Use the program No.
5. OPERATION 4. Use the parameter keys (15) and (16) to change the setting for the selected parameter. (Example: Buttonhole (round) setting value - 3.) (When you press the ENTER key (17), the (14) parameter setting will be changed and the parameter display LED (14) will stop flashing.
5. OPERATION Example 2: This example shows how to set a taper tack for the front tack pattern and an eyelet for the rear tack pattern. 1. Press the SELECT key (13) to change the mode to automatic, test feed or manual mode. Use the program No.
5. OPERATION Example 3: This example shows how to copy the settings for program No. 3 to program No. 11. 1. Press the SELECT key (13) to change the mode to automatic, test feed or manual mode. Use the program No. keys (7) and (8) to select the program number for the program to use (example: program No.
5. OPERATION 5-4-4. Rear tack vector shape programs Parameter No. 37 Setting range 1.Triangle 2.Rectangle 3.Saw-shape 1466Q 1. Triangle • General sewing 2. Rectangle • This is effective for preventing the material from getting stuck in the needle hole when sewing the rear tack, which can happen when using lightweight materials.
5. OPERATION 5-4-5. Underlay programs Four types of underlay patterns are available. These four types can also be combined. Refer to the examples of use to determine which type of underlay to use. Parameter No. 45 Underlays sewn together Saw-shape underlays Rectangle underlays Zigzag underlay stitch 2125Q...
5. OPERATION 5-4-6. Cutter operation The cutter operating pattern can be selected from the following four patterns. • Center knife operation, where the cutter operates when sewing of the buttonhole is complete • Rear knife operation, where the cutter operates when sewing of the buttonhole is complete and the material is fed so that the cutter is near the front tack •...
5. OPERATION 5-4-7. Cycle program This example shows how to set C1 to program No. 3 and C2 to program No. 10. A single cycle program can contain up to nineteen sewing patterns (C1 to C19). (14) (15) (16) (13) (17) 2129Q 1.
5. OPERATION 5-4-8. Changing the production counter • Check that panel DIP switch SW-A4 is at the OFF setting. (Refer to "13. Changing functions using the DIP switches".) (14) (15) (16) (13) (17) 2130Q 1. Press the SELECT key (13) to change the mode to automatic mode.
5. OPERATION 5-4-9. Changing the lower thread counter setting value • Check that panel DIP switch SW-A4 is at the ON setting. (Refer to "13. Changing functions using the DIP switches".) (14) (15) (16) (13) (17) 2130Q 1. Press the SELECT key (13) to change the mode to automatic mode.
5. OPERATION 5-5. Using the program memos Insert the program memos (1) into the rear of the operation box (2) for safekeeping. Program memo contents 1. Easy reference guide 2. Error code table 3. Parameter table 4. Program notes Use a lead pencil to make any additions to the parameter table and for writing anything into the program notes.
5. OPERATION The program numbers for patterns which have been created using the BAS-PC/300 range from P1 to P9. However, program numbers which have not yet been assigned to a program will not appear on the program number LED. → → → → 1 → → → → 2 → → → → 3 → → → → ….. → → → → 90→ → → → P1 → → → → P2 → → → → …… → → → → P9 → → → → 1 → → → → 2 → → → → …… You can check and change the following parameters for patterns which have been created using the BAS- PC/300.
6. CHECKING THE SEWING PATTERN 6. CHECKING THE SEWING PATTERN You can check the sewing pattern which has been programmed, and also the needle zigzagging and feed operation. Checking can be carried out using test feed mode, or by turning the machine pulley by hand in manual mode.
6. CHECKING THE SEWING PATTERN 6-2. Manual mode (for checking the sewing pattern by turning the machine pulley by hand) (14) (13) (17) 2136Q 2135Q 1. Press the SELECT key (13) to change the mode to automatic mode. Use the program No. keys (7) and (8) to select the number for the program to be checked, and then press the ENTER key (17).
7. CORRECT USE 7. CORRECT USE CAUTION Turn off the power switch before installing the needle, otherwise the machine may operate if the treadle is depressed by mistake, which could result in injury. 7-1. Installing the needle 1. Use a Schmetz Nm 134 needle. 2.
7. CORRECT USE 7-2. Threading the upper thread CAUTION Turn off the power switch before threading the thread, otherwise the machine may operate if the treadle is depressed by mistake, which could result in injury. Thread the upper thread correctly as shown in the illustration.
7. CORRECT USE 7-3. 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.
7. CORRECT USE 7-4. Threading the bobbin case CAUTION Turn off the power switch before removing or inserting the bobbin case, otherwise the machine may operate if the treadle is depressed by mistake, which could result in injury. Purl stitch Whip stitch (seal stitch) (plain stitch)
7. CORRECT USE 7-5. Thread tension The shapes of the seams for all patterns which have been stored in programs 1 to 90 can be set using parameter No. 11. Make the following adjustments in accordance with the seam shape which has been set. Zigzag stitch Lower thread tension Upper thread tension...
7. CORRECT USE Thread take-up spring tension Turn the thread tension stud (1) to adjust the thread take-up spring tension to between approximately 0.10 - 0.20 N in accordance with the material to be sewn. Thread take-up spring height Loosen the set screw (2), and turn the entire thread tension adjuster to adjust the thread take-up spring height to between 4 - 6 mm in accordance with the material to be sewn.
8. SEWING 8. SEWING CAUTION Turn off the power switch at the following times, otherwise the machine may operate if the treadle is depressed by mistake, which could result in injury. • When threading the needle • When replacing the bobbin and needle •...
8. SEWING 8-1-1. If the emergency stop switch is pressed during sewing The sewing machine will stop and "E-00" will appear in the parameter display LED (14). Turn the knob of the emergency stop switch to the right to release it. 1.
8. SEWING Emergency stop Thread breakage detection Press the EMERGENCY STOP switch to stop the machine, and then The machine stops when a reset the switch. (When panel DIP switch A-3 is ON, an emergency thread breakage is detected. stop occurs when the treadle is depressed backward.) Thread the thread.
8. SEWING 8-1-3. Thread breakage before sewing is finished Set panel DIP switch A-1 to ON. Even if sewing is complete, leave the work clamp lowered and check the sewing. Then depress the treadle backward to trim the thread and raise the work clamp. If the thread breaks just before sewing is complete, and then sewing is completed without the thread breakage being detected, the following operations are possible.
8. SEWING * DIP switch A-1 = ON Sewing completes with Thread breakage occurs just before sewing is complete, but sewing completes before it is detected no thread breakage (work clamp still lowered) (work clamp still lowered) Thread the thread. Resuming sewing Re-sewing Re-sewing in the next program...
9. MAINTENANCE 9. MAINTENANCE CAUTION CAUTION Turn off the power switch before carrying out cleaning, 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.
9. MAINTENANCE 9-2. Draining the oil 1. Remove the belt cover, and then gently tilt back the machine head. 2. Place the oil tank (1) against the underside of the Bed base work table (2), and then remove the screw (3). 3.
9. MAINTENANCE 9-5. Checking the needle Always check that the tip of the needle is not broken before starting sewing. 2163Q 9-6. Cleaning the length feed plate Clean the length feed plate (1) if foreign materials such as shavings start getting onto the material. 1.
If only one hand is used, the weight of the machine head may cause Ask your Brother dealer or a qualified elec- your hand to slip, and your hand may get trician to carry out any maintenance and caught.
10. STANDARD ADJUSTMENTS 10-2. Needle and hook timing adjustment 1267Q Lowest Mark position 2166Q 2168Q 1306Q After the sewing machine has returned to the home position, press the RESET key before carrying out this adjustment. 1. Loosen the two screws (2) of the rotary hook joint (1). 2.
10.STANDARD ADJUSTMENTS 10-4. Adjusting the inner rotary hook and rotary hook holder overlap Loosen the screw (3) to adjust so that the tip of the rotary hook holder (1) does not protrude past the edge A of the inner rotary hook (2). 2171Q 10-5.
10. STANDARD ADJUSTMENTS 10-7. Adjusting the upper thread trimming The standard distance (A) between the upper thread scissors (1) and the center of the needle is 5.5 to 6.0 mm when the work clamp is lowered by pressing the RESET key after setting the machine to the home position. (A) 5.5 –...
10.STANDARD ADJUSTMENTS 10-7-2. Adjusting the upper thread scissors opening timing After the sewing machine has returned to the home position, press the RESET key before carrying out this adjustment. 2180Q 2182Q Start touching at 1.5 – 2.5 mm 0.5 mm 0.5 mm 0.5 mm Approx.
10. STANDARD ADJUSTMENTS 10-8. Adjusting the lower thread clamp timing Loosen the set screw (2) of the feed arm support (1), and then align the reference line A on feed guide shaft B (3) with the edge of the feed arm support (1). When the feed mechanism moves by approximately 6 - 7 mm, the opening plate (4) will move and the lower thread retainer (5) will open.
11.CHANGING FUNCTIONS USING THE MEMORY SWITCHES 11. CHANGING FUNCTIONS USING THE MEMORY SWITCHES • Refer to the memory switch table for details of memory switch settings. • The memory switches are valid for all programs (program Nos. 1 to 90). •...
11. CHANGING FUNCTIONS USING THE MEMORY SWITCHES Memory switch table Effective for all programs Setting items Setting range Unit Default Cutter power Weak -1 Light 0 Light - Normal 1 Normal 2 Normal - Medium 3 Medium 4 Heavy Strong Work clamp lifting speed –...
12. PROGRAM INITIALIZATION 12. PROGRAM INITIALIZATION (14) 2189Q 12-1. Initializing all programs 1. While pressing the RESET key (3), turn on the power switch. All LEDs on the operation panel will illuminate and the buzzer will sound continuously for 8 seconds. 2.
13. CHANGING FUNCTIONS USING THE DIP SWITCHES 13. CHANGING FUNCTIONS USING THE DIP SWITCHES 13-1. Panel DIP switches 2190Q 1. Slide the panel side cover to open it. 2. Change the DIP switch setting. * Refer to the DIP switch table for an explanation of the functions of each DIP switch. 3.
13. CHANGING FUNCTIONS USING THE DIP SWITCHES Panel DIP switch table DIPSWA Setting item Default Work clamp remains lowered after sewing is complete (lifts when pedal is depressed) Work clamp lifts after sewing is complete – – Emergency stop using work clamp lifter switch enabled during automatic sewing Emergency stop using work clamp lifter switch disabled during automatic sewing Display setting during automatic mode = lower thread counter (Default: 100) Display setting during automatic mode = production counter (Default: 0)
13. CHANGING FUNCTIONS USING THE DIP SWITCHES 13-2. Control circuit board DIP switches 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.
13. CHANGING FUNCTIONS USING THE DIP SWITCHES DIP switch inside the control box table DIPSW1 Setting item Default – – – – – – – – – – – – Three warning beeps Continuous warning beep Needle feed motor excitation turned off during emergency stop and thread breakage Needle feed motor excitation not turned off during emergency stop and thread breakage...
15. ERROR CODE TABLE 15. ERROR CODE TABLE 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.
15. ERROR CODE TABLE Code Cause Remedy E-62 Needle up error during operation Turn off the power. E-63 Needle down error during operation Turn off the power. E-64 Turn off the power. Timing signal error during operation E-70 Machine motor running error Turn off the power.
16. TROUBLESHOOTING 16. TROUBLESHOOTING Problem Cause Check Remedy Page Burrs in needle hole. Needle Replace the needle. Needle is Install the needle Needle position incorrectly installed. correctly. Threading is Thread the upper Upper thread breaks Threading incorrect. thread correctly. Upper thread tension Main and auxiliary Adjust to an is too strong.
16. TROUBLESHOOTING Problem Cause Check Remedy Page Needle is incorrectly Install the needle Needle position installed. correctly. Needle and rotary Needle and rotary hook Adjust the timing of the hook timing timing is incorrect. needle and rotary hook. Buttonhole width or Replace the work Needle breaks Work clamp...