Here's how your machine should be threaded:
Pay particular attention to the two pictures on the far right. The bottom discs are called the thread controller discs, and the spring is called the thread controller spring. The thread goes over the top of and in between the two upper tension discs, under and in between the two lower thread controller discs, on the outside of the thread controller spring, and then gets pulled back behind the small curved hook on the inside thread controller disc. The thread can jump out of that spot and screw up your stitches.
No one lives forever, the trick is creating something that will.
Last edited by DanTwoLakes; 12-09-2011 at 08:39 AM.