Today my issue was with the thread. (Of course I discovered this after hours of trying everything else...rolling eyes) The thread was catching when coming off the sharp edge on the bottom of the cone. I forgot to take a before picture, but this cone is a good example of a sharp edge. The bottom needs to be rounded so it slips over the edge Smoothly. I call this softening the cone.
Note the gentle curve on the bottom of the cone? It's not a huge difference, I don't want it too smooshy.
Lay the cone on it's edge and gently roll it back and forth
and you get a nice smooth edge!
Why a picture of a bowl of ice? Because I didn't want to clean out my freezer for a picture, lol. Did you know freezing dry thread may revive it? Thread can dry out from age or plain ole dry air. Running a humidifier in your sewing room can really help. But in a pinch tossing it in the freezer in an open sandwich bag over night can help restore lost moisture.
A few things to ask yourself before messing with your machines tension.
What has changed sense the last quilt (which quilted fine)
Did I drop the bobbin case (tweaking it)
Different brand of thread?
Dry or old thread?
Did I re-thread it correctly? Did something pop out of line? (always re-thread it first! More than likely something is amiss in the threading)
Is there a fabric issue or combination of fabric issues? (Sheet, batik, tone on tone, metallic, etc.)
Is the sandwich too tight? (loosen one or two clicks)
Lint build up? (Clean under the plate and any thread paths that may have lint build up).
Bad needle? (Too thin of a needle can cause deflection. Or you may need to turn your needle slightly)
Bur on the hook? (try using an emery cord to smooth it)
I'm sure there are many more I'm not thinking of. (Please feel free to add them in the comments)
Dark dyes on fabric or threads can cause breakage as well...but that's a whole other story, lol.
October is getting closer, I really need to figure out what I'm going to do with this guy =)