zozee

Hallelujah! I fixed the tension. I tried 4 things and not sure which one did the trick.

1) used micro vacuum attachments to suction out teeny dust particles I couldn't get with the lint brush, then added a drop of oil
2) changed thread, top and bobbin, from one color to a completely different color, but same brand (Connecting Threads quilting cotton) . For some reason, even though they are the same, the grey felt thicker. I dunno. Might be my imagination.
3) re-inserted the needle (which I changed two days ago). It was not backward, but I did it anyway, and tightened everything up.
4) tried different tension settings, but that didn't change things. The tension is set back to which is where it started.

Here is my test swatch. Grey thread is bad stitches, blue is good.
[ATTACH=CONFIG]619176[/ATTACH]

My hunch is that the micro-vacuuming and adding a drop of oil was the a-ha!