Sewing machine XL 5500 settings

Your bobbin is probably too loose. When you set a new bobbin, stop every now and then and try with your fingers nail if it's nice and tight enough. Not extremely tight, but tight, not loose and moves easily when you set your finger between the threads.

With most fabrics (99%) the plate is fine at the the top position, just with very thick and "fragile" (satins etc) you might need to adjust it.

Settings: Tightest tension for the thinnest materials, more loose for the thicker ones, better have a test piece, it rarely goes under 5 anyway.

Remove the top thread from your machine.
Install a brand new needle.
ALWAYS RAISE the presser foot and then rethread the top thread--verify the thread path is correct.
Set the top tension to the midway point (starting tension setting but may need to be tweaked for your particular machine).

HINT; thread problems appearing under the fabric are usually related to a top thread issue. Thread problems appearing on the top of the fabric are usually bobbin related.

What you are experiencing is called bird nests/thread nests, or what I refer to as thread barfs. The most common fault is the top thread is not seated in the tension disk. Raising the presser foot while threading will allow the thread to seat properly.

What causes Bird Nests Superior Threads

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