Nine times out of ten, it is your needle size. Check what needle is supposed to be used with the type of Superior thread you are using. Ask how I know.....took a FMQ class with my new 8900 that had perfect FMQ at home with a different thread, then I used a "special thread" for the class project. After a hour of breaking, shredding thread and problems with FMQ stitches....I was really upset with this new machine....then I took the spool off of the machine and inside the cone was the needle required for that thread....immediately changed the needle...ABSOLUTE FMQ PERFECTION. Who would have thought?
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