Originally Posted by eparys

When you get back to your project, make sure that you do not "tug" the fabric as you turn it. When I ziz zag edges in raw edge applique, sometimes when the curve is very sharp I will stop, leaving the needle in the down position and the pressure foot up and turn the fabric ever so lightly to prevent me from forcing the fabric against the needle. If you somehow flex the needle on a turn - the hook will not pass by the needle scarf correctly and miss the picking up the top thread.

Here is a great link to how it all works

http://www.threadsmagazine.com/item/...eedle-know-how

Good luck - let us know how you make out!!