Go ahead, ask me how long it took me to make a 10-Minute Table Runner. *waits while you guess* About two hours...but most of that was spent arguing with my machine.
My LQS is rabid about cotton thread for cotton quilts, and carries Gutterman thread. My Nelco I take to class is fine with it, but the Pfaff...not so much. And it's fine in the bobbin, just not on top. The thread breaks every 10 stitches or so, usually more frequently. I changed the needle. I rethreaded. I loosened the tension until the stitch was sloppy and it still kept breaking. I dug out my copy of Alex Askaroff's Tension Fixer and started working my way through the steps. Is it an unbalanced twist? No, not that. Maybe the spool was too big? Wound some onto a bobbin and no, that wasn't the problem either. And then, somewhere in there, he said something about cotton thread occasionally being problematic for some machines. Aha!
So I went back to my old standby, Coats and Clark All Purpose. I tightened the tension to where I usually keep it, and it was fine. Perfect, even. Wonderful long seams of nice balanced stitches. I finished the runner in about 20 minutes. Then I put the Gutterman back in, determined to make it work.
It still doesn't. *Nothing* I do makes the thread not break. What gives? Anybody got any insight, or is this just one of the quirks I'm going to have to live with? How critical is the 'cotton for cotton' rule? I've used C&C for years with no issue, but I'm a newbie to quilting.