No matter where I set my bobbin tension, in order to have uniform, nice looking stitches on the bottom, I must set the top tension so tight that the thread (King Tut) snaps routinely. I have tried everything I can think of and followed countless advice. I attend a Handiquilter class once a month and asked the experts. My needles are correct for the thread, I've checked all locations for lint, used the Towa top and bottom tension gauges with Superior's recommended readings, all to no avail. I don't know what else to do. I need help! Very frustrated.