puckering on back when straight line quilting
On my last few quilts, there has been puckering on the back of my quilt, when the front looks fine. It almost looks like I have been trying to "gather" the fabric. (I think that is the term, it has been quite a few years since I sewed clothes.)
I haven't changed the way I pin, and I only do straight line quilting. Does anyone have any suggestions for me? I keep thinking it is my walking foot or maybe the tension, but I thought I would ask you folks what you thought. The machine goes in for yearly check ups, so I haven't neglected her. I clean lint from around the bobbin after every quilt.
Thanks for any ideas.
Dina