Baby Lock Jewel Service Manual
© Baby Lock, all rights reserved
30
Backlash
Spring
Backlash
spring
adjusting
screw
Bobbin Case Tension Adjustment
•
Paradigm shift from “Never touch the bobbin case tension.” Wound too tight or too loose or
inconsistent problems with bobbin winder. If bobbin is wound poorly the tension will not be
able to be set correctly. Warped bobbin case from dropping. Warped bobbin from winding
too tight (pretension set too tight).
•
Foundation - -bottom like a house – foundation crack story - -it will never be right until the
foundation is corrected or the true cause of the problem is corrected.
•
Bobbin case - -foundation to top tension – spring location – lint built up. With factory set
bobbin thread loaded, you should achieve a 20-25 gram pull.
•
Built in backlash spring – with small screw on the face of the bobbin case, adjust the
backlash spring. It should put slight pressure on the bobbin to prevent the bobbin from
spinning after a customer comes to a sudden stop.