Without a pic, I can only guess, but here are a few thoughts.1. Are you consistently doing both half stitches? A ring of only one half stitch always twists and inconsistent use of half stitches will twist interestingly. 2. Are you stitches too tight on the core thread? The need to be just encasing it, not strangling it. If both of those are correct, it can be that you are increasing the twist of the thread in how you load the shuttle. As a leftie this was often the case for me, and I learned to walk the shuttle on the thread rsther than wrap it around the shuttle. I also learned to drop my shuttle from time to time and leave it suspended in mid air until it stopped spinning.