Is a Bobbin Case Necessary

A bobbin case, when used with the correct bobbin, will hold the bobbin snugly in place, which will allow the machine to neatly unravel it. The bobbin case also adds tension to the bottom thread, much like the tension assembly for the top thread.

Why does my bobbin case rattle?

If the upper thread is incorrectly threaded, the upper thread passed through the fabric cannot be firmly pulled up and the upper thread becomes tangled in the bobbin case, causing a rattling noise.

How do you fix a loose bobbin case?

If the bobbin case doesn’t budge, your bobbin tension is too tight. To tighten your bobbin tension, turn the tiny screw on the bobbin case a smidgen clockwise. To loosen bobbin tension, turn the screw counterclockwise. A quarter turn or less is a good place to start.