Brother S-7780A Instruction Manual Download Page 74

Page: 74 / 84

S-7780A

7. TROUBLESHOOTING

Problem

Possible cause

Page

5 Skipped stitches at sewing

start
Thread unraveling at
sewing start.

・

Is the thread take-up spring tension too strong?

Reduce the tension of the thread take-up spring.

・

Is the thread take-up spring operating range too large?

Lower the position of the thread take-up spring.

・

Is the trailing length of the upper thread too short after thread
trimming?

Adjust the pretension.

・

Are the threads not being trimmed cleanly?

Sharpen the fixed knives, or replace the fixed and movable
knives if necessary. Replace the movable knife.

・

Is the needle too thick?

Replace the needle with a needle that is one rank thinner.

・

Is the length of thread trailing out from the bobbin case after thread
trimming too short?

If the bobbin is spinning loosely, replace the anti-spin spring in
the bobbin case.

・

Is the sewing speed too fast at the sewing start?

Use the slow start key.

・

Is the needle up stop position too high?

Adjust the needle up stop position.

・

Is the upper thread trailing length too short after thread trimming?

Turn on the "Prev. thread away" function.

・

If the thread is pulling out at the sewing start, try the following
remedies.

1.  Check the upper thread trailing length.
2.  Set the slow start number to "3" or less.
3.  Re-adjust the upper thread trailing length to make it longer.
4. Select "Prev. thread away PARA" from "Function setting".

(Refer to "4-6. Setting basic functions".)

(1) Set the 2nd stitch pitch to "3".
(2) Increase the current stitch pitch settings for the 1st and

2nd stitches by about 0.5 to 1.

・

Is the needle hole in the needle plate too large for the needle being
used?

Replace the needle place with one with a needle hole that is
one rank thinner.

・

Is the presser foot groove too wide?

Replace the presser foot with one that has a narrower groove
so that it presses the material at the needle drop position.

・

Is the sewing machine starting to sew before the presser foot has
dropped?

Lower the presser foot before starting sewing.

・

Is the presser foot being raised before the sewing machine has
stopped sewing?

Raise the presser foot after the sewing machine has stopped
sewing.

59*

・

27*

24*

27*

6 Large bird's nests are

forming at the sewing
start.

・

Is the upper thread trailing length too long after thread trimming?

Increase the tension of the pre-tension.

0749M

Summary of Contents for S-7780A

Page 1: ... this manual before using the machine Please keep this manual within easy reach for quick reference SINGLE NEEDLE DIRECT DRIVE LOCK STITCHER WITH SIDE CUTTER ELECTRONIC FEEDING SYSTEM AND THREAD TRIMMER INSTRUCTION MANUAL ...

Page 2: ...l 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 Follow the instructions from training personnel and instructors regarding safe and correct operation before operating the machine so that you will know how to use it correctly ...

Page 3: ...hich follow this term indicate situations where failure to follow the instructions could result in death or serious injury CAUTION The instructions which follow this term indicate situations where failure to follow the instructions may result in minor or moderate injury Symbols This symbol indicates something that you should be careful of The picture inside the triangle indicates the nature of the...

Page 4: ...r cord from the wall outlet Lightning may cause problems with correct operation Do not connect anything to the USB port other than the USB media If this is not observed problems with operation may result Installation 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 s...

Page 5: ... other injuries Use both hands to hold the machine head when tilting it back or returning it to its original position If only one hand is used the weight of the machine head may cause your hand to slip and your hand may get caught 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 inflammatio...

Page 6: ...tion To prevent accidents and problems do not modify the sewing machine including the control devices yourself Brother will not be held responsible for any accidents or problems resulting from modifications made to the equipment ...

Page 7: ...e moving thread take up 5 6 7 High temperature warning display 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 Direction of operation 8 Safety devices A Finger guard B Thread take up cover C Motor cover D Pulse motor cover 9 Do not hold Problems with operation or injury...

Page 8: ...S 7780A vi 1768D Oil tank ...

Page 9: ... 6 6 Setting lower thread counter operation 29 4 6 7 Prev thread away 30 4 6 8 Correction sewing function 1 31 4 6 9 Correction sewing function 2 32 4 7 Memory switch setting method 33 4 8 List of memory switch settings 34 4 9 Setting design stitches 38 4 9 1 Switching the display item 39 4 9 2 No of stitches setting 40 4 9 3 Direction setting 41 4 9 4 Pitch setting 42 4 9 5 Design stitch sewing m...

Page 10: ...tting speed Max stitch length 4 mm Presser foot height Lifting lever 5 mm Knee lifter 13 mm Feed dog height 1 0 mm Needle DB 1 11 18 Cutting width Needle cutting surface 3 2mm 1 8 6 4mm 1 4 Motor AC servo motor Control box power supply voltage 2 Single phase 200V 230V 3 phase 200V 230V Power consumption 550 VA Control circuit Microprocessor 1 Standard feed locus 2 If using a power supply voltage w...

Page 11: ...t caught About the machine set up location Do not set up this sewing machine near other equipment such as televisions radios or cordless telephones otherwise such equipment may be affected by electronic interference from the sewing machine The sewing machine should be plugged directly into an AC wall outlet Operation problems may result if extension cords are used Carrying the machine The sewing m...

Page 12: ...hstand the vibration of the sewing machine Drill holes as indicated in the illustration below 2 2 Installation 1 Control box Oil pan 1 Control box 2 Bolts 4 pcs 3 Nuts 4 pcs 4 Spring washers 4 pcs 5 Washers 4 pcs 2 Connecting rod 6 Connecting rod 7 Nut 1412D Cotton stand hole Cord hole Head rest hole Control box mounting hole Control box mounting hole 1413D ...

Page 13: ... 1 Rubber cushions 2 pcs 5 Machine head 1 Hinges 2 pcs 2 Machine head 3 Head rest NOTE Bind the cords together and pass them through the cord hole 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 1414D 1797D 1773D Packing ...

Page 14: ...ew 5 to adjust so that the amount of play in the knee lifter plate 4 is approximately 10 mm 5 After adjustment is completed securely tighten the nut 3 6 Loosen the nut 6 7 Turn the adjusting screw 8 to adjust so that the presser foot 7 is at the desired position within a distance of 13 mm from the needle plate when the knee lifter plate is fully pressed 8 After adjustment is completed securely tig...

Page 15: ...hed before it is used for the first time and also after long periods of non use 1 Hold the base of the nozzle of the accessory oil tank 1 and use scissors to cut about half way along the straight section A of the nozzle 2 Loosen and remove the nozzle and then remove the seal 2 3 Tighten the nozzle 4 Tilt back the machine head 5 Remove the rubber cap 3 and pour lubricating oil into the oil cover 4 ...

Page 16: ...wise there is the danger that fire or electric shocks could occur 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 2 4 1 Connecting the cords 1 Cords 1 1 Solenoid connector 14 pin 2 Sewing machine motor encoder connector 10 pin 3 Feed motor encoder connector 6 pin 4 Oper...

Page 17: ...llow wire is the ground wire 2 Insert the power plug into a properly grounded electrical outlet NOTE Make sure that the ground connections are secure in order to ensure safety For Europe specifications and 220 V specifications refer to 2 4 2 Other cords Ground symbol Green and yellow wire ground wire 1794D Ground symbol Green and yellow wire ground wire Europe specifications Gray ground wire ...

Page 18: ...S 7780A 2 INSTALLATION 9 3 Cords 2 1 Machine motor connector 4 pin 2 Feed motor connector 6 pin 1421D Lower the tab 3 Push in securely until the tabs 3 engage ...

Page 19: ... specifications Europe specifications 1 Filter box 2 Screws 4 pcs 3 Connector 4 CE bush plate 5 Screws 2 pcs 6 CE D cord cover 7 Screws 2 pcs 8 Staples 4 pcs 9 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 NOTE Take care when tapping in the staples 8 to make sure that they ...

Page 20: ...stop Do not operate the upper knife set lever 2 and release lever 3 while the sewing machineis operating Installing the sewing scraps guide U When it is difficult for the sewing scraps to drop below the bed install the supplied sewing scraps guide U 4 to the auxiliary needle plate 5 with the two screws 6 Installing the needle plate cover If it is not necessary to deposit the cut sewing scraps belo...

Page 21: ...acktack stitches are being displayed the indicator of the end backtack key 7 will illuminate and the number of C stitches will appear in the C column and the number of D stitches will appear in the D column When continuous backtack stitches are displayed the indicator of the continuous backtack key 8 will illuminate and the number of A B C and D stitches will appear in order starting from the left...

Page 22: ...es the number of backtack stitches 0 to 9 in the A B C and D columns of the display are sewn continuously After the sewing machine sews a full cycle of stitches set by A B C and D the thread is trimmed 9 Thread trimming disable F1 key When this key is pressed so that the indicator illuminates the sewing machine stops in the needle up position without thread trimming being carried out even if the t...

Page 23: ...ng is carried out After it has finished normal sewing continues for as long as the treadle remains depressed NOTE If the treadle is returned to the neutral position the sewing machine will continue operating until the set number of start backtack stitches has been sewn 4 End backtacking is carried out After it has finished the thread is trimmed automatically and the sewing machine stops in the nee...

Page 24: ... single cycle the thread will be trimmed automatically and then the needle bar will stop in the needle up position NOTE If the treadle is returned to the neutral position while continuous backtacking is being carried out the sewing machine will stop at the point where the treadle returns to the neutral position If the treadle is depressed again operation will resume from the point where it was int...

Page 25: ...g value increases by 0 05 When the key is pressed the setting value decreases by 0 05 NOTE The setting range is from 0 05 to 4 00 3 The 3 digit display will switch from the normal sewing pitch to the backtack sewing pitch and the backtack sewing pitch can be set only when the indicators are illuminated simultaneously 1 Refer to 4 3 2 Backtack sewing speed setting method 1 When the function for mem...

Page 26: ...Sewing speed display ON Maximum sewing speed setting value ON ON Backtack sewing speed setting value Counter display ON Lower thread counter value Flashing Lower thread counter warning enabled ON ON Production counter value ON ON Needle replacement counter value Flashing Flashing Needle replacement counter warning enabled Locus display ON Locus setting value Program display ON Program number or se...

Page 27: ... illuminate and the setting value for the backtack sewing speed will appear in the 4 digit display NOTE If you press the key once more the indicator will switch off and the display will return to the maximum sewing speed setting value 3 Press the C D keys to change the setting value When the D key is pressed the setting increases by 100 When the C key is pressed the setting decreases by 100 NOTE T...

Page 28: ...sed to let you know approximately how much lower thread is remaining The lower thread counter should be used as a guide only The value displayed by the lower thread counter display is reduced by 0 1 from the initial setting value each time the number of stitches x sewing pitch reaches 0 1 m and a warning is given when the counter goes below 0 Sewing will be possible even after the treadle is retur...

Page 29: ...ounter value will appear in the 4 digit display 3 After the thread trimming operation is complete the counter will be incremented NOTE The counter is incremented when the treadle is depressed backward even if thread trimming is set to disabled 4 When the production counter is displayed you can press the C or D key to adjust the counter value 0 to 9999 When the D key is pressed the counter value in...

Page 30: ...counter is reduced by 1 from the initial setting value each time the sewing machine sews 100 stitches and a warning is given when the counter goes below 0 Sewing will be possible even after the treadle is returned to the neutral position and the sewing machine stops However after the treadle has been depressed backward and thread trimming has been carried out sewing using the treadle will no longe...

Page 31: ...the 4 digit display 2 Press the C D keys to change the setting value When the D key is pressed the setting value increases by 1 When the C key is pressed the setting value decreases by 1 NOTE The setting range is from 0 to 3 0 The feed dog moves along the standard locus 1 The feed dog moves along special locus 1 2 The feed dog moves along special locus 2 3 The feed dog moves along special locus 3 ...

Page 32: ...tting Refer to 4 6 4 Illumination LED brightness A08 LEd Level 5 Refer to 4 6 5 Lower thread counter operation A09 UtCt None Refer to 4 6 6 Prev thread away A11 PtA None Refer to 4 6 7 Prev thread away pitch at 1st stitch A12 PtP1 3 30 Prev thread away pitch at 2nd stitch A13 PtP2 2 20 Hand switch correction sewing function A31 HSCF 1 Single correction sewing Refer to 4 12 Function other than hand...

Page 33: ...splayed 2 Displaying the needle up stop and needle down stop setting values When the key is pressed the setting value is displayed 3 Setting the needle up stop and needle down stop positions When the D key is pressed the UP display will appear When the C key is pressed the dn display will appear When the key is pressed the initial value will be reset NOTE If the key is pressed once more the indica...

Page 34: ...yed When the key is pressed the previous setting is displayed 3 Displaying the thread trimming disabled setting value When the key is pressed the setting value is displayed 4 Setting thread trimming to disabled or enabled When the D key is pressed the on display will appear When the C key is pressed the oFF display will appear When the key is pressed the initial value will be reset NOTE If the key...

Page 35: ...04 Corr When the key is pressed the next setting is displayed When the key is pressed the previous setting is displayed 3 Displaying the correction sewing setting value When the key is pressed the setting value is displayed 4 Setting correction sewing When the D key is pressed the on display will appear When the C key is pressed the oFF display will appear When the key is pressed the initial value...

Page 36: ...ing value is displayed 4 Setting slow start When the D key is pressed the setting value increases in the order oFF 1 2 3 4 When the C key is pressed the setting value decreases in the order 4 3 2 1 oFF When the key is pressed the initial value will be reset Sewing speed for first 4 stitches when slow start is enabled 1 400 400 400 4000 2 400 400 4000 4000 3 700 700 4000 4000 4 Set using memory swi...

Page 37: ...s pressed the previous setting is displayed 3 Displaying the illumination LED light setting value When the key is pressed the setting value is displayed 4 Setting the illumination LED light When the D key is pressed the setting value increases from 1 through to 9 When the C key is pressed the setting value decreases from 9 through to 1 When the key is pressed the initial value will be reset NOTE I...

Page 38: ...y is pressed the previous setting is displayed 3 Displaying the lower thread counter operation setting value When the key is pressed the setting value is displayed 4 Setting lower thread counter operation When the D key is pressed the on display will appear When the C key is pressed the oFF display will appear When the key is pressed the initial value will be reset NOTE If the key is pressed once ...

Page 39: ...splayed When the key is pressed the previous setting is displayed 3 Displaying the Prev thread away setting value When the key is pressed the setting value is displayed 4 Setting Prev thread away When the D key is pressed the on display will appear When the C key is pressed the oFF display will appear When the key is pressed the initial value will be reset NOTE If the key is pressed once more the ...

Page 40: ...y is pressed the next setting is displayed When the key is pressed the previous setting is displayed 3 Displaying the correction sewing function setting value When the key is pressed the setting value is displayed 4 Setting the correction sewing function When the D key is pressed the setting value increases from oFF to 1 through to 9 When the C key is pressed the setting value decreases from 9 thr...

Page 41: ... next setting is displayed When the key is pressed the previous setting is displayed 3 Displaying the setting value for a function other than correction sewing When the key is pressed the setting value is displayed 4 Setting a function other than correction sewing When the D key is pressed the setting value increases from oFF to 1 through to 16 When the C key is pressed the setting value decreases...

Page 42: ...e keys to select the number for the memory switch which is different from the initial value When the key is pressed while holding down the key the next setting item is displayed When the key is pressed while holding down the key the previous setting item is displayed 4 Changing the memory switch setting value When the D key is pressed the setting value increases or it turns ON When the C key is pr...

Page 43: ...operation of the standing operation pedal takes priority ON Treadle operation is still enabled after standing operation pedal has been used alternating operation is possible OFF Treadle operation is disabled after standing operation pedal has been used 011 0 1 0 1 Operation when standing up variable speed pedal is ON 0 Sewing speed corresponds to treadle depression amount 1 Operates at the sewing ...

Page 44: ... position Needle down stop position initial setting value Upper shaft reference position correction value Needle down stop position correction value Feed motor settings 200 to 299 No Setting range Initial value Setting units Setting details 200 50 150 100 1 Forward direction pitch correction ratio 201 50 150 100 1 Reverse direction pitch length correction ratio 202 50 150 100 1 Start backtacking B...

Page 45: ... set to 4 Refer to 4 6 4 Slow start 404 300 4000 sti min 4000 sti min 100 sti min 2nd stitch sewing speed for slow start Only enabled when slow start A04 is set to 4 Refer to 4 6 4 Slow start 405 300 4000 sti min 4000 sti min 100 sti min 3rd stitch sewing speed for slow start Only enabled when slow start A04 is set to 4 Refer to 4 6 4 Slow start 406 300 4000 sti min 4000 sti min 100 sti min 4th st...

Page 46: ...hine motor and off according to the timing set by No 503 502 90 270 Degrees 180 Degrees 1 Thread presser ON timing upper shaft angle When No 501 is set to OFF or 2 nothing is displayed The setting is disabled 503 270 430 Degrees 320 Degrees 1 Thread presser OFF timing upper shaft angle When No 501 is set to OFF nothing is displayed The setting is disabled 504 50 50 Degrees 0 Degrees 1 Feed timing ...

Page 47: ...each one can contain up to a maximum of eight steps By setting design stitches you can sew patterns at special pitches which cannot be used when normal sewing only is carried out Design stitches cannot be set or edited when memory switch No 312 is set to 1 or 2 Example of design stitch setting Step Item 1 2 3 4 No of stitches 1 1 0 Direction FW FW FW Sewing pitch 3 00 1 00 3 00 To end the program ...

Page 48: ...played 2 Switching to setting item display If you press the key the setting item will change The display item changes in the order of No of stitches Feed direction Pitch No of stitches each time the key is pressed 3 When the key is pressed the step number increases by 1 1 When the key is pressed the step number decreases by 1 2 1 If you press the key when the step number is 8 the design stitch num...

Page 49: ...e to change and then switch to number of stitches setting mode 3 Set the number of stitches When the C key is pressed the number of stitches for the selected step decreases by 1 When the D key is pressed the number of stitches for the selected step increases by 1 If the number of stitches is set to 1 or more the setting for the selected design stitch step is applied to the sewing operation The num...

Page 50: ...rection When the C key is pressed the feed direction for the selected step will be set to forward fw forward direction When the D key is pressed the feed direction for the selected step will be set to reverse bw reverse direction The reverse direction setting is only enabled when the sewing pattern is normal sewing or fixed stitch sewing If reverse fixed stitch sewing continuous backtack sewing or...

Page 51: ...hile referring to 4 9 1 Switching the display item select the step of the design stitch which you would like to change and then switch to pitch setting mode 3 Set the pitch When the C key is pressed the pitch for the selected step decreases by 0 05 mm When the D key is pressed the pitch for the selected step increases by 0 05 mm 4 Press the key Setting mode will be exited and normal operation will...

Page 52: ...e maximum pitch display Sewing at the normal pitch will then be possible Note When memory switch No 407 MSW407 Synchronized not synchronized to pitch is set to ON synchronized the backtack sewing pitch will appear from looking at the display to be DS 1 but because backtack sewing is not a function which is supported for design stitches backtack sewing will actually be carried out at the maximum pi...

Page 53: ...etting item Read write direction B81 PRGR Read all programs USB media Panel Sewing machine B82 PRGW Write all programs USB media Panel Sewing machine B83 MSWR Read all memory switches USB media Panel Sewing machine B84 MSWW Write all memory switches USB media Panel Sewing machine B85 ADTR Read all data USB media Panel Sewing machine B86 ADTW Write all data USB media Panel Sewing machine B87 PDIW W...

Page 54: ...tch to initialization mode and C01 ALLC will appear in the display 2 Press the keys to select the item to be initialized 3 digit display 4 digit display Initialization item C01 ALLC Clear all C02 MSWC Memory switch initialization C03 PGMC Program initialization C04 PDIC Production data initialization 3 Press the key for 2 seconds or more When initialization is complete the 4 digit display will cha...

Page 55: ...and switch setting Settings for correction sewing switch A36 Settings for other than correction sewing switch Settings for correction sewing switch This setting is enabled when the correction sewing setting A04 is ON Setting value Function Setting details Settings for correction sewing switch OFF Disabled 1 Single correction sewing Stops after sewing a single stitch 2 Continuous correction sewing ...

Page 56: ...the treadle backward while the sewing machine is stopped the thread will be trimmed without end backtacking being carried out End backtacking is only canceled once 8 Standard locus Changes to standard locus while the switch is being pressed 9 Standard locus switching Switches between the locus which is set and the standard locus each time the switch is pressed 10 Special locus 1 Changes to special...

Page 57: ...keys to set to A31 or A32 and then press the key to select Menu No Setting details A31 Settings for correction sewing switch A32 Settings for other than correction sewing switch 3 Press the D C keys to select the desired setting value When the key is pressed the initial value will be reset When the key is pressed the mode returns to function setting mode When the key is pressed the mode returns to...

Page 58: ...50 When the key is pressed the initial value will be reset When the key is pressed the mode returns to function setting mode When the key is pressed the mode returns to sewing standby mode 4 12 3 2nd pitch setting If 2nd pitch has been set and the hand switch is pressed during sewing the stitch pitch will change to the pitch set as follows 1 Switching to 2nd pitch ratio screen In function setting ...

Page 59: ...s Use both hands to hold the machine head when tilting it back or returning it to its original position If only one hand is used the weight of the machine head may cause your hand to slip and your hand may get caught The following cleaning operations should be carried out each day in order to maintain the performance of this machine and to ensure a long service life Furthermore if the sewing machi...

Page 60: ...lease lever 1 The upper knife 2 will rise 2 Raise the presser foot 3 Remove the two screws 3 and then remove the needle plate 4 4 Use a soft wire brush to clean any dust from the feed dog 5 5 Install the needle plate 4 with the two screws 3 1782D ...

Page 61: ... power cord plug at the following times The machine may operate if the treadle is depressed by mistake which could result in injury When carrying out inspection adjustment and maintenance When replacing consumable parts such as the rotary hook and knives Always be sure to turn off the power switch and then wait one minute before opening the motor cover If you touch the surface of the motor it may ...

Page 62: ...2 Raise the presser foot 1 by using the lifting lever 2 3 Remove the rubber cap 5 from the face plate 4 Loosen the bolt 6 and then move the presser bar 7 up or down until the presser foot 1 is at the standard height of 5 mm 5 Tighten the bolt 6 6 Install the rubber cap 5 7 Adjust the presser foot pressure using the presser adjusting screw 4 and then tighten the nut 3 NOTE After adjusting check tha...

Page 63: ... 2 The standard height of the feed dog 3 when it is raised as far as possible above the surface of the needle plate is 1 0 mm 5 Turn the machine pulley to move the feed dog 3 to its highest position above the needle plate 6 Tilt back the machine head 7 Loosen the screw 4 8 Turn the feed lifting shaft crank 5 to move the feed bracket 6 up and down 9 Tighten the screw 4 10 After adjusting press the ...

Page 64: ...o the standard position In order to prevent puckering lower the front of the feed dog 3 Fig B In order to prevent the material from slipping raise the front of the feed dog 3 Fig A 9 Securely tighten the set screw 6 10 After adjusting press the SEL key 2 NOTE The height of the feed dog 3 will change after the angle has been adjusted so it will be necessary to re adjust the height of the feed dog 3...

Page 65: ...e side plate 6 Loosen the two set screws 6 of the vertical cam 5 and then turn the vertical cam 5 slightly to adjust the timing To advance the needle timing turn in the direction of A To retard the needle timing turn in the direction of B To prevent material slippage from occurring retard the needle timing Fig B To improve thread tightening advance the needle timing Fig A NOTE If the vertical cam ...

Page 66: ...er edge of the needle hole to the rotary hook tip will be 0 5 to 0 7 mm at this time 1 Turn the machine pulley to raise the needle bar 1 from its lowest position until reference line b is aligned with the lower edge of the needle bar bush 2 as shown in the illustration 2 Loosen the three set screws 5 and then align the rotary hook tip 3 with the center of the needle 4 The distance between the tip ...

Page 67: ...n run the sewing machine at the normal sewing speed for 8 seconds Any type of paper can be used as the lubrication amount check sheet 1 5 Check the amount of oil which has spattered onto the sheet If adjustment is necessary carry out the following operations in Adjusting the lubrication amount Adjusting the lubrication amount 1 Tilt back the machine head 2 Turn the rotary hook adjusting screw 3 to...

Page 68: ... 1 Turn off the power switch 2 Remove the presser foot needle plate and feed dog 3 Tilt back the machine head 4 Loosen the screw 2 of the thread trimmer lever 1 5 Install the movable knife 4 to the movable knife holder 5 with the two screws 3 1789D 1441D ...

Page 69: ...er cam lever assembly 3 is sitting on top of the thread trimmer cam 2 then move the thread trimmer lever 7 to adjust its position so that the tip of the fixed knife 5 and the blade of the movable knife 6 are meshed by 1 to 1 5 mm and then tighten the screw 8 Tighten the screw 8 so that there is no play in the forked shaft 9 The lower thread finger 10 must be underneath the movable knife 6 3 Instal...

Page 70: ... that the roller shaft 4 of the thread trimming cam lever assembly 3 touches the hollow c of the thread trimmer cam 2 and so that the clearance between the edge of the thread trimmer 2 and the roller 4 is 0 5 to 1 0 mm and then tighten the set screw 5 Fig A 2 Check that the edge of the thread trimmer cam 2 and the roller shaft 4 do not touch when the roller shaft 4 returns to the right Fig B Tight...

Page 71: ... two bolts 4 4 Turn the machine pulley to raise the upper knife 2 to its highest position 5 Loosen the two screws 8 of the knife holder 7 6 Move the knife holder 7 toward the needle plate 5 until the relative positions of the upper knife 2 and the needle plate 5 are as shown in diagram C and then tighten the screws 8 If the upper knife 2 is pressed too tightly against the needle plate 5 the upper ...

Page 72: ...3 3 Install the auxiliary needle plate 10 with the two screws 9 4 Install the needle plate 8 with the two screws 7 Turn the machine pulley and adjust the feed dog 14 so that it is centered right left and front back over the groove in the needle plate 8 and then tighten the screws 13 5 Tilt the machine back shift the sewing scraps guide 12 right or left from the underside so that the guide is 0 0 5...

Page 73: ...er thread is not tight Is the upper thread tension too strong Is the lower thread tension too weak Adjust the lower thread tension or upper thread tension 3 Loops appear in seam Is the thread path not smooth enough Use a file with a fine grain or sandpaper to polish smooth the thread path Is the bobbin turning smoothly Pull out the lower thread to check that there is no slackness in the thread ten...

Page 74: ... Turn on the Prev thread away function If the thread is pulling out at the sewing start try the following remedies 1 Check the upper thread trailing length 2 Set the slow start number to 3 or less 3 Re adjust the upper thread trailing length to make it longer 4 Select Prev thread away PARA from Function setting Refer to 4 6 Setting basic functions 1 Set the 2nd stitch pitch to 3 2 Increase the cur...

Page 75: ...ake up spring operating range too large Lower the position of the thread take up spring to as low a position as possible Is the presser foot pressure too strong Adjust the presser foot pressure Is the sewing speed too fast Gradually reduce the sewing speed Is the angle of the feed dog correct Tilt the front of the feed dog down slightly 17 55 9 Lower thread is tangled at the sewing start Bobbin is...

Page 76: ...dpaper Alternatively replace the damaged part 50 6 50 11 Thread breaks during backtack sewing Is the backtack sewing speed too fast Use the panel to reduce the backtack sewing speed 18 12 Backtack sewing pitch varies depending on the sewing direction Backtack edge is not aligned Adjust using memory switch No 201 35 13 Thread tightening around X over seam areas Is the height of the feed dog correct...

Page 77: ...ve any pieces of broken needle sticking in the material If the needle breaks search for all pieces until the whole of the needle is found again Furthermore we recommend that thorough steps be taken to account for such needles to comply with product liability regulations 55 56 22 17 Material does not cut properly Is there no clearance between the upper knife and the needle plate or is the upper kni...

Page 78: ... Is the operation panel connector inside the control box disconnected Insert the connectors securely 7 9 10 7 22 The illumination becomes momentarily darker or flickers The illumination may become momentarily darker or flicker when the sewing machine starts or stops depending on the power supply in the environment where the sewing machine is being used This is not a sign of a malfunction 1453D 145...

Page 79: ...the cause of the error and then turn the power back on Items with a in the Page column should only be checked by a qualified technician For items with appearing in the Page column ask the place of purchase for advice Connector layout diagram 1584D 1454D Connector P1 Power supply connector Sewing machine motor connector Feed motor connector Connector P4 Connector P3 Connector P2 Connector P6 Connec...

Page 80: ...id not reach the specified value when the sewing machine motor stopped Turn off the power and check if the sewing machine motor or thread trimming mechanism is stiff or not E113 The needle down stop position exceeded the specified value when the sewing machine motor stopped Turn off the power and check if the sewing machine motor or thread trimming mechanism is stiff or not E130 Sewing machine mot...

Page 81: ...ry main internal P C board Turn the power off and then back on again E441 Data could not be read from the backup memory main internal P C board Turn the power off and then back on again E442 Back up memory main internal P C board data was abnormal so settings were initialized Turn the power off and then back on again E450 Model settings could not be read from machine head memory internal panel Tur...

Page 82: ...k the connection of the USB media E886 Problem with version update file detected during version updating Turn off the power and then repeat the version update procedure E887 Version update file could not be written during version updating Turn off the power and then repeat the version update procedure E889 Incorrect data written to flash memory Turn off the power and then repeat the version update...

Page 83: ...S 7780A 8 7 SEGMENT DISPLAY 74 8 7 SEGMENT DISPLAY ...

Page 84: ...80D E 2020 01 D 2 Please note that the contents of this manual may differ slightly from the actual product purchased as a result of product improvements 2020 Brother Industries Ltd All Rights Reserved This is the original instructions ...

Search results

Summary of Contents for S-7780A

Reviews:

Related manuals for S-7780A

Brands by name

Popular brands

Brother S-7780A, Instruction Manual

Search results

Summary of Contents for S-7780A

Reviews:

Related manuals for S-7780A

Brands by name

Popular brands