Why does the bottom tread come out loose and loopy

First, check the stitching to verify that it is in fact the bobbin thread that is loose & loopy. Usually, loopy thread under the fabric is the upper thread--which, if that is the case, is an indication it is either threaded incorrectly or the upper tension is too loose.

Make sure you are using a brand-new needle.
Always RAISE the presser foot and then thread the upper thread making sure that every guide and the correct path is followed.

Set the upper tension to the midway point between high & low number and re-test the stitching. Re-adjust as needed. The tension is correct when both upper and bobbin threads meet in the middle of the fabric.

Understanding Thread Tension Threads

If it is in fact the bobbin thread causing looping, it could be that the bobbin case is not threaded properly or the tension is way off.

Liz Kettle adjusting your bobbin case tension 1 wmv

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