I forgot to ask if your cone of King Tut thread is placed on a vertical thread stand. It will not come off the cone correctly if placed in the horizontal spool pin on the top of the machine. Cones of thread must have the thread come off them from above, if not they may catch and cause tension problems and breakage. I purchased the spool holder that attaches to the back of my Horizon, much nicer than the cheap plastic one I had been using. Just another suggestion.