Pintucks

I worked out the problems, sort of: First of all, when thread breaks and pintucks don't look like I think they should, I go into a crazed troubleshooting mode. And with a serger, there are so many variables that may be causing the problem, you can fix one and then cause another.
I think the coverstitch looper wasn't threaded exactly right to start with. But I started playing with all the tensions at the same time I was adjusting the looper, and that made everything worse. In the end, I got pintucks with the recommended tensions...though that left needle thread did still sometimes break.
However, I learned something about pintucks: they aren't exactly what I though they were. They aren't like darts. I was trying to apply pintucks to a top that was too wide, and I expected them to draw in the fullness. But they barely do that at all. They really only draw in a tiny amount and make a little hill in the fabric.

Plus, the entire project was NOT suited to serger sewing at all because I was making the tucks begin and end in the middle of a finished garment. Anyone experienced with sergers would have told me not to use a serger for this project. Instead I figured it out for myself after I made the first tuck. DUH.... you can't stop in the center of a fabric with a serger!!!! But stubborn as I am, I went ahead and made 13 tucks, struggling to cut. the threads at the bottom of each one. Then I had to thread a hand needle multiple times to pull all those hanging threads to the wrong side.

Ridiculous...I will never do that again! But at least I know about serger pintucks now.