Go to this site and WATCH all the videos. You will learn an amazing amount of info on threads, tension and you will have very little problems in the future. The lessons are from Superior thread and you might think it is just a sales pitch. This is high quality thread and when you watch the one about monofillament you will be amazed.
http://www.youtube.com/watch?v=YzD-o...01QRL-QPUNrCbg