Adjusting Bobbin Thread Tension - Singer 6660 Instruction Manual

ADJUSTING BOBBIN THREAD TENSION

BOBBIN THREAD TENSION REQUIRES ADJUSTMENT
LESS FREQUENTLY THAN THE TOP THREAD TENSION.
Fabric puckers
If the tension is well balanced, but the fabric puckers badly,
both top and bobbin thread tensions may be too tight and
have to be adjusted. To test if the bobbin thread tension is
correct, suspend the bobbin case by the thread and jerk
it once. Correct bobbin tension will result in the thread
unwinding only one or two inches. If too loose it will unwind
continuously. If too tight the thread will not unwind at all.
When adjusting the tension on the bobbin case, make only
slight adjustments with a screwdriver.
Increase
Decrease
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