Well i learned my lesson. i got my machine back from being serviced and decided to make some large hexagon coasters. i did a zig zag stitch and had trouble with some stitches being straight not zig zag. i thought of taking my machine back in. then filled the bobbin and noticed my top thread having a bad area. i cut that off and proceeded to stitch. well my top thread then shredded twice on me.
i grabbed it off and replaced with a dark green i'd gotten at an LQS and no more problems. even with the oldthread in the bobbin. so my machine doesn't have to go back and i just went to Connectingthreads.com and ordered more essential threads.
talk about slow to learn!