So many times, we get called on longarm tension problems. And when we look closely, the thread isn't actually between the tension disks. Longarm tension disks don't open when you lift the presser foot, like a domestic machine. You really have to pull the thread into them. When you adjust the tension on a domestic machine, a quarter of a turn is a lot. But when you adjust the tension on a longarm, you can crank the knob half-way around, and it won't make as much difference because the screw is so fine.
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