I have a brother cs6000i....my tension is completely screwed up!! The hubbs helped me take it apart and clean all the dustballs from the bobbin case and.....ewwww! But the tension is still wrong. No matter what number it's on the top thread is little bumps and the bobbin thread is loose...i can pull my thread right out of the bobbin loops. I've tried re-threading, and different bobbins. Now I'm stuck wondering if i should bring it to a shop---which i have no idea who is good here on the island--or just getting a new machine since this one was less then $200 if i remember correctly. So bummed!! I have an antique machine in good condition---still upstate at my dad's. I haven't tried it out yet but the woman that gave it to my mom said her mom used it for piecing and quilting. grrr.