Bird nesting on back stitch, changed tension and cleaned, any suggestions

Hm, if it is occurring only when reverse stitching, that may be a machine problem needing professional service.

Usually, bird nesting results when the upper thread is not firmly seated in the tension disk. Be sure to Always Raise the Presser Foot when threading the upper thread. Try to make sure the needle is in the highest position before beginning to stitch.

Could possibly also be the needle. Try a brand new needle or a different kind of needle, ie quilting or embroidery needle rather than a universal needle. May be an incompatibility of needle & thread.

Check that the tension is correct--both the upper and bobbin threads meet in the middle of the fabric.

What causes Bird Nests Superior Threads

Fly little nestling Ditching the Thread nests part 1

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