background image

 

 

SL-1110 

8. THREAD TENSION

9. CLEANING

14

8-2. Adjusting the presser foot pressure 

 

Correct stitches 
 

 

     Upper thread 

 

 

 

 

 

 

 

Skipped stitches occur 

 

 

 

 

 

Increase the pressure. 

 

Uneven stitch length 

 

 

 

 

 

 

 

Stitches are puckered 

 

Decrease the pressure. 

 

The presser foot pressure should be as weak as possible, 
but strong enough so that the material does not slip. 

1.  Loosen the adjusting nut (1). 
2.  Turn the presser adjusting screw (2) to adjust the presser 

foot pressure. 

3.  Tighten the adjusting nut (1). 

 
 
 
 
 

 

 
 
 
 

9. 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. 

Be sure to wear protective goggles and gloves when handling the lubricating oil, so that it does not get into your 
eyes or onto your skin. If care is not taken, inflammation can result. Furthermore, do not drink the lubricating oil. 
Diarrhea or vomiting may result. 
Keep the oil out of the reach of children.

 

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 machine has not been used for a long period of time, carry out the 
following cleaning procedures before using it again. 

1.  Raise the presser foot. 
2.  Remove the two screws (1), and then remove the needle 

plate (2). 

3.  Use a soft wire brush to clean any dust from the feed dog 

(3). 

4.  Install the needle plate (2) with the two screws (1). 
 
 
 
 
 
 
 

(

Continued on next page

)

 

0894M 

0895M 

0896M 

0897M 

2182M

3854M

Becomes stronger 

Becomes weaker 

Summary of Contents for S-7550A

Page 1: ...SL 1110 S 7550A HIGH SPEED SINGLE NEEDLE STRAIGHT LOCK STITCHER Please read this manual before using the machine Please keep this manual within easy reach for quick reference 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: ...e situations where failure to follow the instructions could cause injury when using the machine or physical damage to equipment and surroundings Symbols This symbol indicates something that you should be careful of The picture inside the triangle indicates the nature of the caution that must be taken For example the symbol at left means beware of injury This symbol indicates something that you mus...

Page 4: ...allation 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 approximately 30 kg The installation should be carried out by two or more people Do not connent the power cord until installation is complete The machine may operate if the treadle is depressed by mistake whi...

Page 5: ...or 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 Be sure to wear protective goggles and gloves when handling the lubricating oil so that it does not get into your eyes or onto your skin If care is not taken inflammation can result Furthermore do not drink the lubricating oil Diarrhea or vo...

Page 6: ...ave been removed or are difficult to read please contact your nearest Brother dealer 2 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 1 3 Direction of operation Safety devices A Finger guard B Thread take up cover C Belt cover 3871M Oil pan 3825M 3824M ...

Page 7: ... the stitch length 11 7 SEWING 12 7 1 Sewing 12 7 2 Backtacking 12 8 THREAD TENSION 13 8 1 Adjusting the thread tension 13 8 2 Adjusting the presser foot pressure 14 9 CLEANING 14 10 STANDARD ADJUSTMENTS 16 10 1 Adjusting the thread take up spring 16 10 2 Adjusting arm thread guide R 17 10 3 Adjusting the presser foot height 17 10 4 Adjusting of the feed dog height 18 10 5 Adjusting the feed dog a...

Page 8: ...lever 9 Bobbin winder Safety devices 10 Finger guard 11 Thread take up cover 12 Belt cover 2 MACHINE SPECIFICATIONS 3 5 Use For medium weight materials For heavy weight materials Max sewing speed 5 500rpm Normal sewing speed 5 000rpm 4 000rpm Max stitch length 4 2mm 5mm Lifting lever 6mm Presser foot height Knee lifter 13mm Feed dog height 0 8mm 1 2mm Needle DB x 1 DP x 5 11 18 19 22 3826M 3827M ...

Page 9: ...cks could occur Install the correct belt cover which corresponds to the motor being used Motor Use one of the clutch motors given in the table at right as the motor Refer to the instruction manual for the motor for details on installing and using the motor Motor pulley and V belt Select the correct motor pulley and V belt by referring to the table below to suit the power frequency of your area 50H...

Page 10: ...use other injuries Do not connect the power cord until installation is complete The machine may operate if the treadle is depressed by mistake which could result in injury 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 Install the belt cover to the machine head 5 1 Ins...

Page 11: ...f the needle plate 2 Lower the presser foot 5 by using the lifting lever 4 3 Loosen the nut 6 4 Turn the screw 8 to adjust so that the amount of play in the knee lifter 7 is approximately 2 mm when the knee lifter plate 1 is gently pressed 5 Securely tighten the nut 6 6 Loosen the nut 9 7 Turn the screw 10 until the distance between the end of the screw 10 and the knee lifter 7 is approximately 8 ...

Page 12: ...3 by approximately 5 mm and then place the bobbin winder 4 so that it is parallel with the belt hole in the table 3 Install the bobbin winder 4 to the table with the two screws 5 4 Pull the bobbin presser arm 1 back and check that there is approximately 8 mm of clearance between the bobbin winder wheel 2 and the belt 3 8 Belt cover 1 Loosen the three screws 1 on the machine side plate by 4 5 turns...

Page 13: ...ine head 4 Align screw 1 B with the groove 6 in belt cover U 5 and then place belt cover U 5 onto the machine pulley 5 Tighten screws 1 B 1 C and 4 to secure belt cover U 5 6 Place belt cover D 7 so that it overlaps the belt cover 2 by 2 3 mm and then provisionally tighten the two screws 8 Continued on next page 3840M 3841M 3839M ...

Page 14: ... of belt cover D 7 as far as it will go 9 Pull belt cover D 7 toward you until there is no clearance between the belt cover 2 and the cover 9 of belt cover D 7 10 Fully tighten the two screws 8 Refer to step 6 9 Cotton stand 1 Cotton stand NOTE Securely tighten the nut 4 so that the two rubber cushions 2 and the washer 3 are securely clamped and so that the cotton stand 1 does not move 3842M 3843M...

Page 15: ...wing machine should always be lubricated and the oil supply replenished before it is used for the first time and also after long periods of non use Use only the lubricating oil Nisseki Mitsubishi Sewing Lube 10N VG10 specified by Brother If this type of lubricating oil is difficult to obtain the recommended oil to use is Exxon Mobil Essotex SM10 VG10 1 Tilt back the machine head 2 Slowly pour in l...

Page 16: ...far as it will go making sure that the long groove on the needle is at the left and then securely tighten the screw 2 6 2 Removing the bobbin case CAUTION Turn off the power switch before removing the bobbin case 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 tr...

Page 17: ...the adjustment screw 7 to adjust the bobbin winding amount To increase the winding amount Tighten the screw To decrease the winding amount Loosen the screw NOTE The amount of thread wound onto the bobbin should be a maximum of 80 of the bobbin capacity 6 4 Installing the bobbin case CAUTION Turn off the power switch before installing the bobbin case The motor will keep turning even after the power...

Page 18: ...will make threading easier and it will prevent the thread from coming out at the sewing start 6 6 Adjusting the stitch length Turn the stitch length dial 1 until the desired stitch length number is aligned with the pin 2 above the dial The larger the number the longer the stitch length will be The numbers on the dial are for use as a guide The length of the finished stitches may vary depending on ...

Page 19: ...if the treadle is depressed by mistake which could result in injury When threading the needle When replacing the bobbin and needle When not using the machine and when leaving the machine unattended 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 7 1 Sewing 1 Turn on the power switch 2 Depress ...

Page 20: ...d tension too strong Increase the upper thread tension Decrease the lower thread tension Upper thread tension too strong or lower thread tension too weak Decrease the upper thread tension Increase the lower thread tension Lower thread tension Adjust by turning the adjustment screw 1 until the bobbin case drops gently by its own weight while the thread end coming out of the bobbin case is held Uppe...

Page 21: ...pressed by mistake which could result in injury Be sure to wear protective goggles and gloves when handling the lubricating oil so that it does not get into your eyes or onto your skin If care is not taken inflammation can result Furthermore do not drink the lubricating oil Diarrhea or vomiting may result Keep the oil out of the reach of children The following cleaning operations should be carried...

Page 22: ...OW mark add more lubricating oil Refer to page 8 Use only the lubricating oil Nisseki Mitsubishi Sewing Lube 10N VG10 specified by Brother If this type of lubricating oil is difficult to obtain the recommended oil to use is Exxon Mobil Essotex SM10 VG10 If the lubricating oil is contaminated remove the oil cap screw 7 and drain the oil Clean off any dirt on the collection magnet 8 and in the oil p...

Page 23: ...If the power switch needs to be left on when carrying out some adjustment be extremely careful to observe all safety precautions 10 1 Adjusting the thread take up spring Thread take up spring position The standard position of the thread take up spring 1 is 6 8 mm 4 6 mm for 5 specifications above the surface of the thread guide 3 when the presser foot 2 is lowered 1 Lower the presser foot 2 2 Loos...

Page 24: ... The standard height of the presser foot 1 is 6 mm when the presser foot 1 is raised by means of the lifting lever 2 1 Loosen the nut 3 of the adjustment screw 4 and then turn the adjustment screw 4 so that there is no pressure applied to the presser foot 2 Raise the lifting lever 2 The presser foot 1 will also rise 3 Remove the oil cap 5 4 Loosen the bolt 6 and then move the presser bar 7 up or d...

Page 25: ... shaft 2 is aligned with the feed rocker bracket arm 3 and the feed dog 1 is parallel to the needle plate 1 Turn the machine pulley to move the feed dog 1 to its highest position above the needle plate 2 Tilt back the machine head 3 Loosen the two set screws 4 4 Turn the shaft 2 in the direction of the arrow within a range of 90 with respect to the standard position In order to prevent puckering l...

Page 26: ... highest position until it is flush with the top of the needle plate 2 1 Remove the rear cover 2 Loosen the two set screws 4 of the vertical cam 3 and the two set screws 6 of the horizontal cam 5 and then turn the vertical cam 3 and the horizontal cam 5 slightly to adjust the timing The vertical cam 3 and horizontal cam 5 are linked by a pin so that if either one is turned the other will turn with...

Page 27: ...the illustration 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 D 2 as shown in the illustration The needle should rise by 1 8 mm 2 2 mm for 5 specifications and the distance from the needle hole to the tip of the rotary hook should be 0 5 0 7 mm 2 Loosen the set screws 5 and then align the t...

Page 28: ...d it there Then 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 adjusting screw 3 ...

Page 29: ...too weak or is the upper thread tension too strong Adjust the lower thread tension or upper thread tension 13 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 not turning smoothly Pull out the lower thread to check that there is no slackness in the thread tension or replace the bobbin or bobbin case...

Page 30: ... height Is the bobbin scratched If the bobbin is damaged smooth it with an oiled grindstone or replace it 14 18 7 Large degree of puckering excess tension Is the upper thread tension too strong Make the upper thread tension as weak as possible Is the lower thread tension too strong Make the lower thread tension as weak as possible Is the needle tip blunt Replace the needle if it is blunt Is the ne...

Page 31: ...ion of the thread take up spring Is the rotary hook feed dog or other part damaged If they are damaged smooth them with an oiled grindstone or replace the damaged parts Is the thread path damaged If the thread path is damaged smooth it with sandpaper or replace the damaged part 9 11 13 16 11 Broken needles Is the material being pushed or pulled with excessive force during sewing Is the needle prop...

Page 32: ...INSTRUCTION MANUAL SL 1110 S 7550A SA8760 101 2007 06 BC 1 http www brother com ...

Reviews: