i don't know about that convertible foot set your speaking of but i did buy the bobbin case. the tension on that bobbin case is set at the factory just for free motion quilting. i never mess with the tension on any bobbin case so i believe the special bobbin case just for free motion quilting is an absolute must. i could not afford to have all my quilts done by a long armer so i decided if i was to keep on quilting i had to try that special bobbin case and sure enough that solved my problem as i now free motion all my quilts. they may not meet the standard of a long armer but looks pretty good to me. here's a close up of one i just finished.
donna
using special bobbin case for free motion quilting - and the back looks good too.
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