It was a spool that I inherited from another trimmer, so I wouldn't blame the mfg (though I'll check if you want), but rather storage conditions. I'm guessing the thread is 5-7 years old, and when I first inspected it, it seemed fine. As I took more off, I could feel it sticking together.

Problem solved.
I also posted this to a group on FaceBook, and came up with several suggestions:
Replace needle (I do this this frequently)
Loosen tension (I did this)
Lengthen stitch ( I also did this)

Problem still existed, but only with that particular thread. I replaced the whole spool, voila, problem solved. Turns out it was an old spool and the thread was sticking together.

HI I did a couple of things: removed cover then scored the foam, that took care of most of it, then I steamed it and worked (rubbed) the material, and that took care of the rest of it.
The problem wasn't the glue, which I use sparingly, but that I folded the material when I was doing the pleats. On the subsequent ones, I was careful not to fold the portion that already had pleats, and they turned out beautifully.

Machine is a Juki DNU 1541.

Figured it out!
Thanks!

Thanks everyone!
I ended up fitting the cover, cutting a small hole, and stretching over.
Next time when I have more time, I'll mess around with removing post.

OK, so drag and drop works!
Here is the 68 Chrysler

1968 Chrysler New Yorker. Seats were horrible, required major foam work. Customer let me do it as I saw fit![img]http://Chrysler 68.JPG[/img]...hmm, have to see how to get image address!