All of a sudden my machine will not sew correctly. The lower thread is ravelled and the upper thread is not a straight stitch. I have changed the thread and needle, threaded the machine several times, same with the bobbin and does not work properly.
I have hemmed jeans and altered a formal dress recently and cannot understand what could the problem be?

Lilia, January 2011

Hello Lilia,
Sounds like you need to reset thge tension until you get it right.
Ken

ken, January 2011