Originally Posted by
QuiltnNan
is it possible that there is a thread caught in the bobbin tension slot?
That was my thought as well. There may me a piece of lint or a piece of thread caught under the bobbin case spring (that little flat piece that is held by the screw). I have that happen to me - and sometimes it is not obvious.
Here is a great article from Threads magazine - it may or may not be of help but worth the read!
http://www.threadsmagazine.com/item/...nsion/page/all