Rule one: Don't monkey with the bobbin tension.
Rule two: If you MUst monkey with the bobbin tension, make a Teeny Tiny marker mark at the screw where it is set before you monkey with it, so when you monkey with it and find out that was not the problem you can set it back where it was!!
Rule three: Don't monkey with the bobbin tension.
Rule four: Unless you MUst. Then see Rule two.
;) ;) ;)
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