TROUBLE SHOOTING: CAUSES AND REMEDIES
REMEDY
THREAD FORMS LOOPS
CAUSE
SHRINKING OR PUCKERING OF THE SEAM
IRREGULAR STITCHES
MACHINE DOES NOT RUN FREELY AND MAKES A NOLSE
Thread tension not properly regulated
Needle thread properly threaded and/or bobbin thread
Thread check spring not working properly
not properly wound
Thread size not suited to fabric
Thread machine properly and/or wing bobbin thread correctly
See Size of needle and thread
Have spring replaced
Read instructions for regulating needle-and bobbin thread tension
Tension too tight
Sewing foot pressure too strong
Needle and bobbin threads of poor quality
Bobbin thread unevenly wound
Machine needs oiling
Dust and thread in shuttle
Wrong oil used, has now clogged machine
Drive belt tension too tight
Read instructions for regulating needle-and bobbin thread tensions
Read instructions for regulating sewing foot pressure
Use top quality threads
Re-wind bobbin
Read instructions on how to oil
Read instructions on how to clean shuttle race
Clean machine carefully and re-oil with top quality oil
Loosen tension of drive belt
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TROUBLE SHOOTING: CAUSES AND REMEDIES
NEEDLE THREAD BREAKS
CAUSE
REMEDY
BOBBIN THREAD BREAKS
STITCHES ARE LEFT OUT
NEEDLE BREAKS
Needle not properly threaded
Thread tension too tight
Something wrong with the needle
Thread is too heavy for needle
Thread check spring is broken
Needle not properly inserted
Needle plate, shuttle or sewing foot damaged
Bobbin thread entangled because of incorrectly wound bobbin
Bobbin thread not under tension spring on bobbin case
Needle not properly fitted on needle bar
Needle bent or blunt
Needle worn
Needle bent
Needle not properly fitted
Fabric too heavy or too hard
You are pulling on the fabric
Thread properly
loosen tension
Replace needle
Change
Have a new spring fitted
Insert needle properly
Replace
Wind bobbin correctly
Thread bobbin correctly
Replace
Fit needle properly
Use needle of correct size
Do not pull
Fit needle properly
Replace
Replace