Brother TZ1 B651 Guide

Industrial Sewing Machine Repairs
MADE EASYWith QWIK-Fix Teach Yourself Guides and Manuals
Brother TZ1 B651
QFBBR TZ1B651
Artizan 196 High Road Wood Green London ENGLAND N22 8HH
www.seweazi.com
BASIC REPAIRS &
ADJUSTMENTS

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At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic
of any of the data provided in any of their publications
QWIK-Fix-Publications™ READ FIRST
IMPORTANT NOTICE:
PLEASE NOTE:
If it is felt that carrying out any of the instructions listed in this manual
or CD are not within the capabilities of the person about to attempt the
adjustments you must seek the assistance of a qualified engineer.
QWIK-Fix-Publications DO NOT guarantee that the enclosed instructions
will solve any or all of the readers sewing machine breakdown problems
but advise that the information is a general guide to problem solving and
general adjustments only.

Qwik-Fix-Publications™
Brother TZ1 B651
BASIC REPAIRS & ADJUSTMENTS
CONTENTS SECTION
Repairs and Adjustments
Bobbin Base Replacement 1:1
Bobbin Base Retainer 1:3
Check Spring Adjustment 2:1
Check Spring Replacement 2:2
Feed Setting 3:1
Hook Timing 5:1
Hook lateral adjustment 5:2
Needle bar Settings 6:2
Needle Insertion 6:4
Needle Types/Sizes 6:5
Needles Using The Correct Type and Size 6:6
Needle Design 6:7
Stitch Formation 12:1
Tension (Lower) 13:2
Tension (Upper) 13:3
Thread Types/Sizes 14:1
Threading 14:3
Parts Description
Inner Machine UPPER 20:5
Inner Machine LOWER 20:6
QFBBR TZ1B651

TROUBLE SHOOTING FOR LOCKSTITCH SEWING MACHINES
BOBBIN AND BOBBIN CASE PROBLEMS Section
Bobbin case falls out 17:6
Bobbin case doesn’t fit in bobbin base 17:6
Bobbins don’t fit in bobbin case 17:6
BOBBIN WINDER PROBLEMS
Bobbin winder doesn’t drive 17:6
Bobbin winder thread uneven 17:6
Bobbin winder thread loose1 17:6
Bobbin winder thread tight1 17:6
Bobbins don’t fit winder 17:6
CHECK SPRING PROBLEMS
Check spring breaks easily 17:6
Check spring jams 17:6
FEED DOG PROBLEMS
Feed dog hits needle plate 17:7
Feed dog out of alignment 17:7
HOOK PROBLEMS
Hook jams 17:7
Hook area noisy 17:7
Hook timing keeps going out 17:7
Machine jams 17:7
NEEDLE PROBLEMS
Needle plate centre bends 17:7
Needles bend 17:7
Needles break 17:7
Needles fall out of needle bar 17:7
NEEDLE BAR PROBLEMS
Needle bar jams or seizes 17:7
PRESSER FOOT PROBLEMS
Presser foot jams up 17:8
Presser foot doesn’t lift high enough 17:8
Presser foot lifts too high 17:8
Presser foot doesn’t hold materials 17:8
STITCH FAULTS
Miss stitching 17:8
Stitch uneven 17:8
STITCH LENGTH PROBLEMS
Reverse stitch is too small 17:8
Stitches too small 17:8
Stitches too large 17:8
Stitches vary in size 17:8
THREAD TAKE UP LEVER PROBLEMS
Take up lever loose 17:9
TENSION PROBLEMS
Tension lower 17:9
Tension upper 17:9
Thread slips out of tension unit 17:9
Tension release doesn’t operate 17:9
Thread catches under materials 17:9
Thread loops under materials 17:9
THREAD PROBLEMS
Thread breaks 17:9
Thread frays or shreds 17:9
QFBBR TZ1 B651

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At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™ 1:1
Brother TZ1 B651
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS :
Bobbin Base Replacement
1. Remove the presser foot,needle plate .feed and bobbin case .
2. Turn the hand wheel towards you to observe that there are 3 screws holding the GIB plate in place
Fig 1 . Remove all 3 screws which will release the gib plate.
3. Turn the hand wheel slowly towards you until you see the hook point Fig 2.
4. With the hook point in position as Fig 3 remove the BOBBIN BASE by tilting it from the bottom. Fig 4
5. With the new base in your left hand present it at an angle Fig 4 to the hook ensuring that it locates
into the bobbin base finger Fig 5.
6. With the bobbin base located correctly turn the hand wheel towards you until you can see where the
GIB plate has to be refitted Fig 1.
7. Fit the GIB plate into position and secure the 3 retaining screws. Put a spot of mineral oil around the
base and gib plate to help smooth running in.
8. Pull machine back into its normal working position and proceed to re -assemble the presser foot,
feed and needle plate. ©
9. Fit bobbin and bobbin case.
Now test the machine for stitching quality and adjust tensions if necessary
Side Views of the Hook and Bobbin Base
Fig 1 Fig 2 Fig 3
Fig 4 Fig 5
Gib Plate
Gib Screws
Hook Point
Bobbin Base
Retainer Slot
Hook Point
New Bobbin Base
Hook
Ba
se Retainer
Hook
Bobbin Base

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publications
QWIK-Fix-Publications™ 1:3
Brother TZ1 B651
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS :
Bobbin Base Retainer
1. Push the machine forward to expose the underside of the machine.
2. Depending on the style of base retainer it should be similar to FIG 1
But may have the retaining screw the opposite side to that in the fig.
3. To replace undo the screw holding the retainer and pull the retainer away from the machine.
4. When replacing it ensure you connect the bobbin base retaining finger in the slot of the bobbin base.
©
N.B
The retainer may be in a slightly different location to the one shown here but the slot in the
bobbin base will be exactly the same and the retainer will look very similar to the one shown
below.
Fig1
Base Retainer
Screw
Bobbin Base
Bobbin Base
Retaining Finger

COPYRIGHTS © 2004 QWIK-Fix-Publications™
At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™ 2:1
Brother TZ1 B651
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS
Check Spring Adjustment
With the machine threaded and fabric under the presser foot turn the hand wheel towards you to
produce 3 or 4 stitches. STOP
Now continue to turn the hand wheel towards you until the thread take up lever Fig 1 is at its highest
point. STOP
The thread should have pulled the check spring down from its stop or rest point.
Continue turning the hand wheel slowly towards you until the eye of the needle has just entered the
fabric. STOP
The check spring should now be resting with no more tension on it.©
If it rests too early (before the eye has entered the fabric) slacken the tension unit screw Fig 2 and turn
the tension unit to the left about 1/8th of a turn and lock the screw back up.
If it rests too late (after the eye has entered the fabric) slacken the tension unit screw
Fig 2 and turn the tension unit to the right about 1/8th of a turn and lock the screw back up.
Continue to check and adjust as required.
Fig 1 Fig 2
FIG 3
Check spring
Thread Take Up Lever
Thread Take Up Lever
Screw position is to the right of the tension unit in the
head casting.
Decrease check
Tension Unit
Check Spring adjuster Increase check

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At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™ 2:2
Brother TZ1 B651
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS
:
Check Spring Replacement
1. Remove tension unit from the machine see FIG 2
2. To remove tension stud and discs complete loosen screw on tension unit see FIG 1
3. Remove the check spring from the back of the stud.
4. Fit a new spring.
5. Refit the stud to the unit tighten the stud screw FIG 1
6. Refit the tension unit to the machine. ©
7. To complete refer to the Check Spring Timing section
FIG 1 FIG 2
Thread Take Up Lever
Screw position is to the right of the tension unit in the
head casting.
Tension Unit
Tension stud retaining screw
Tension release
pin
Check Spring

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At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™3:1
Brother TZ1 B651
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH ANY ADJUSTMENTS :
Feed Dog Settings
Feed dog height plays 2 important functions:
1- To feed materials as evenly as possible to give a regular stitch length.
2- To aid the upper thread take up lever to complete the draw of the thread before the
feed drops to return to feed forward again.
The optimum setting for the feed is as Fig 1.
To adjust :
Turn balance wheel towards you until the feed is at its maximum height. STOP.
©
Push machine back on its hinges and locate the feed height fork adjuster FIG 2
Slacken screw and move feed to desired position as FIG 1. Tighten screw and test
machine.
Fig 1 Fig 2
Adjuster Screw
Hook

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At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™ 5:1
Brother TZ1 B651
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS
Hook Timing
1. Remove the needle plate, feed dog and presser foot.
2. Insert a new needle(Long groove to the front. facing you)
3. Set the needle bar alignment to the central position
4. Turn the hand wheel towards you(NEVER AWAY FROM YOU) until the needle reaches the bottom of its stroke. Fig
1STOP!
5. Continue turning the hand wheel towards you until the needle has lifted approximately 2/3mm from the bottom of its
stroke. Fig 2.STOP!
6. At this point the hook point should be in line with the centre of the needle Fig 3.If it is the hook timing is correct and
proceed to the next section 5:2 lateral hook adjustment. If the timing is incorrect continue as follows.
7. Slacken the screws that hold the hook to the drive shaft and “PINCH TIGHTEN” one screw.
8. Turn the hand wheel towards you until the needle reaches the bottom of its stroke Fig 1.STOP!
9. Continue turning the hand wheel towards you until the needle has risen 2/3mm from the bottom of its stroke Fig 2.STOP!
10. Rotate the hook so that the point aligns centrally to the needle Fig 3..ENSURE THAT THE AIR GAP BETWEEN THE
HOOK POINT AND THE NEEDLE IS NO MORE THAN 0.02mm Fig 4 (paper thickness) Tighten all screws. That’s how
easy the hook timing is….
11. Proceed to section 6:2 needle bar height adjustment.
Fig 1 Fig 2 Fig 3 (side view) Fig 4 (side view)
Needle bar
Needle
Bottom Of
Needle
bar Stroke
2/3mm Lift
Bottom
Timed
Hook
Eye of
Needle
Air Gap
Max
0.2mm
Hook
Point

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At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™ 5:2
Brother TZ1 B651
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS
Hook lateral Adjustments
12. With the needle plate, feed dog and presser foot still removed.
13. Ensure the needle is new and the long groove is facing you.
14. Set the needle bar alignment to the central position
15. Turn the hand wheel towards you(NEVER AWAY FROM YOU) until the hook point aligns with the centre of the needle
Fig 3 and that the air gap does not exceed the thickness of 1 piece of normal 80gm paper Fig 4. If it does then slacken
the hook timing screws and align as Fig 4.
16. Tighten the timing screws and check again. Adjust until the setting is correct.
Fig 1 Fig 2 Fig 3(side view) Fig 4 (side view)
Needle bar
Needle
Bottom Of
Needle bar
Stroke
2/3mm Lift
Bottom
Timed
Hook
Eye of
Needle
Air Gap
Max
0.01mm
Hook
Point

COPY RIGHTS ©2004 QWIK-Fix-Publications™
At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™6:2
Brother TZ1 B651
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH ANY ADJUSTMENTS :
Needle bar Settings
NEVER ADJUST THE NEEDLEBAR HEIGHT UNTIL YOU HAVE CHECKED THE
HOOK TIMING IS CORRECTLY SET
Set the machine into straight stitch mode .
Set the needle bar to the central position.
Remove needle plate and presser foot.
Turn balance wheel TOWARDS you (never away) until the needle has reached the
bottom of its stroke (Fig 1) STOP !!
Continue to turn balance wheel TOWARDS you until the hook point aligns with the
needle. STOP!!
If the needle bar height is correct the point of the hook will be aprox 2mm above the eye
of the needle . (Fig 2) ©
To adjust remove the side face plate exposing the needle bar adjuster screw(Fig 3) and
slacken needle bar clamp screw . Adjust the height and re tighten needle bar clamp
screw.
Fig 1 Fig 2 Fig 3
Bottom Of Needle bar
Stroke
2mm
Hook Point
Inner Faceplate
Presser
Bar
Needle bar
Adjusting
Screw

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At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™ 6:4
Brother TZ1 B651
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS
Needle Insertion
Ensure that the needle is fitted right up into the needle bar
and that the LONG GROOVE is facing you (to the front ) Fig 1 ©
Fig 1
Needle
Clamp
Screw
Needle Eye
Long Groove Facing
You

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publications
QWIK-Fix-Publications™ 6:5
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS
Needle Types and Sizes
All needles have a LONG groove on one side and a SCARF on the other.
With very few exceptions industrial machine needles are round shanks at the top of the
needle .
The points however, vary according to the types of material you may want to sew or
even more important is the capability of your machine to sew a particular product.
EG:
Leather machines usually utilise a cutting point such as a narrow wedge or triangular tip
Textiles machines mainly use round tips, but if you are using your machine for more that
one style of material you must be aware that your needle is as equally important as your
thread.
Needle Sizes
Old Size System 9 11 12 14 16 18 ©
New Size System 65 70 80 90 100 110
Needle Points
SES Ballpoint
R Round
NW Narrow Wedge
PCL Narrow Wedge
D Triangular
TRI Triangular
LR Left Reverse Twist Narrow Wedge
Ensure that you have the correct size and type of needle for your materials AND your
THREADS See THREAD TYPES/SIZES 14:1
Fig 1
TRI
NW
R
LR
D PCL RTW

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At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™ 6:6
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS
Using The Correct Type and Size of Needle
NOTE : These are only guides and should not be deemed to be the only or exact
options
Textiles: Use Sizes
( Depends On Thread Thickness Being Used )
Cottons R from size 70 to 110
Stretch Fabrics SES ballpoint from size 60 to 100
Light Upholstery R from size 90 to 130
Light Textiles R from size 60 to 90
Leather : ©
Light Shoes NW or TRI from size 90 to 130
Heavy Shoes LR or RTW from size 140 to 250
Saddlery LR or RTW from size 180 to 280
Handbags NW or TRI from size 90 to 130
Belts NW or TRI from size 90 to 130
Sheepskin:
Coats NW or R from size 110 to 140
Moccassins NW or R from size 110 to 140
Webbing:
Seat Belts R from size 160 to 250
Safety Harnesses R from size 140 to 250
Canvas:
Tents R from size 120 to 180
Tarpaulins R from size 120 to 230
PVC:
All Types R from size 90 to 180

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At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™ 6:7
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS
Needle Design © Needle Design
Side View Long Groove View
Shank
Blade
Scarf
Eye
Point
Shank
Long Groove
Eye
Point

COPYRIGHTS ©2004 QWIK-Fix-Publications™
At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™12:1
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS :
:
How A Stitch Is Formed
The needle enters the work and continues to its lowest point of travel.
As the needle starts to rise from the bottom of its stroke the thread is gently trapped in
the long groove of the needle forcing the thread on the scarf side to be thrown out into
what is known as LOOP FORMATION.
This loop can be forced to be small or large depending how long the TIMING of the hook
is.
The longer the hook takes to reach the needle the larger the loop formation will be.
Normal textile timing is usually around 2/3mm, but for heavy products such as saddlery it
may be necessary to retard the timing to even 4/5mm. ©
Once the thread has been successfully picked up by the hook point the hook continues to
rotate to carry the thread under the bobbin base and over the bobbin case trapping the
bobbin thread completing what is known as a LOCKSTITCH
LOCKSTITCH LOOP FORMATION
Thread
Needle
Fabric
Loop Formation
Hook Pick Up
Point
Needle Eye 2/3mm lift from
the bottom of the
needle stroke

COPYRIGHTS © 2004 QWIK-Fix-Publications™
At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS :
Lower Tension
Fig 3 indicates the correct tension of both the bobbin and needle threads
If you have tension as Fig 1 or 2 it could be that the bobbin tension is too tight or loose.Check if the
bobbin is threaded and inserted and correctly threaded.
Are you using the correct needle size? Are you using the correct thread? YES !!
Check the following adjustments……
Adjustments
©
1. Remove the bobbin case and bobbin from the machine.
2. With a FULL bobbin threaded in the tension spring pull a small amount of thread through
3. With the thread held firmly allow the bobbin case to fall slowly see FIG 4.
If it moves rapidly you need to increase the tension adjusting screw clockwise Fig 5.
If it doesn´t move decrease the tension by turning the screw anti clockwise Fig 5 about 1/16th
of a turn and test again. Repeat the adjustment until the desired effect has been achieved as section 3
above.
FIG 1 FIG 3 FIG 4
FIG 2 FIG 5
13:2

Copyrights © 2004 QWIK-Fix-Publications™
At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS :
ALWAYS CHECK THE THREADING AND THE BOBBIN TENSION FIRST
Upper Tension
Fig 3 is correctly balanced needle and bobbin thread tensions
Often the upper tension is wrongly assumed to be the problem for poor tension quality due to the
difficulty in understanding what is deemed to be the correct settings. So we will try to help by simplifying
the process of identifying the correct method of checking and adjustment.
If you have tension as Fig 1 or 2 it could be that the upper tension is too tight or loose BUT WAIT ! Is
the upper thread correctly threaded , are you using the correct needle size, are you using the correct
thread, is the bobbin correctly inserted and threaded ? Check all before making any adjustments .
Adjustments ©
Remove the presser foot and with the presser then lower the presser foot bar. With the needle threaded,
turn the hand wheel towards you until the needle is almost touching the needle plate FIG 5(no fabric in
machine) Pull the thread towards the right of the machine and if the tension is almost correct the needle
will bend aprox 2 mm out of line of the centre of the needle hole (Fig 5) before it allows you to pull any
thread through.
Adjust as required FIG 4 Decrease will allow the thread to come through the needle with less bending
(less tension).
FIG 1 FIG 3 FIG 4
FIG 2 FIG 5 +
-
13:3

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At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™ 14:1
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS :
Thread Types and Sizes
Threads are as important to the function of your machine as any mechanical adjustment that you may
already be aware of .
Unlike needles threads increase in size with the lower the number.
EG:
TKT 120 Would be used with a 80/90/ 100 or even 110 needle dependent on the material being sewn.
TKT10 would be used with a 180/200/230 needle (Usually used in the heavy leather trades)
See examples below ©
Make up Size Products Suggested Needle Size
Spun Polyester TKT 180 Overlockers 60 to 80
Spun Polyester TKT 120 General Textiles 60 to 110
Core Spun PolyesterTKT 75 Soft Furnishings 90 to 130
Bulk Nylon TKT 180 Underwear Coverseam LOOPERS ONLY
And Overlocker
Bonded Nylon TKT 40 Leather,Heavy Upholstery 90 to 140
Bonded Nylon TKT 20 Heavy Leather,Saddlery 120 to 180
Webbing,Canvas
Bonded Nylon TKT 10 Very Heavy Leather 180 to 280
Tarpaulins,Webbing
Terylene TKT 30 Tents,Upholstery 140 to 180
Terylene TKT 20 Tents, Upholstery 140 to 180
Kevlar TKT 10 Parachutes,Heavy 180 to 280
Fireproof Products
NB.
TWISTS
Threads are either twisted left or right.
Under normal circumstances you would only use a right twist thread on the LEFT needle of a TWIN
NEEDLE machine.