The thread tension mechanisms, one for the upper thread and one for the lower thread, prevent either thread from pulling the entwine point from out of the middle of the material.
2.
The screens virtually eliminate the trial and error that goes into achieving complicated stitch patterns, displaying a matrix of variables that includes stitch width and length, thread tension, sewing speed and presser-foot pressure.
3.
Thread tension correct and incorrectIdeally, the lockstitch is formed in the center of the thickness of the material that is to say : ideally the upper thread entwines the lower thread in the middle of the material.
मोबाइल