Here is a post from my facebook page that will really help when you get thread in and out of the tension or thread that is shredding and breaking at the needle. This is shown on a serger but the premise is the same on a sewing machine. You do not even have to un-thread the machine sometimes, just turn the spool over and continue. Other times it may work best to turn the spool and re-thread. Be sure to use a thread net when needed.