Hi, Just another suggestions....I have an APQS longarm...one of the suggestions I got was to get a couple of extra bobbin cases which I did....I was having problems with tension and talked to one of the local dealers....she just suggested replacing the bobbin case as it sounded to her like it was just worn out.....I did...put in one of my spares adjusted the tension a tad and problem gone....drives me nuts some times trying to figure it out....I learned to rethread and I also have learned to check the tension spring on the upper thread path to make sure it moves when I tug on the top thread....as I sometimes either miss or have my thread jump out of one of the thread guides....