The other thing to check is whether you have long stitches or skipped stitches. Skipped stitches are when the needle goes into the fabric but does not form a stitch. Long stitches look similar, but the needle doesn't go down at all. If you have long stitches it could be the encoders are not working correctly (usually not keeping contact with the rails). If it's skipped stitches then it is not the stitch regulator/encoders, but something keeping the stitch from being formed.

Just a couple other thoughts... I know it will skip stitches if the fabric is stretched too tight. Try loosening the presser foot tension -- to the red line. Adjust the height of your poles so so the fabric is more level with the sewing machine bed.

Good Luck to You!

I feel your pain!!! I was dismayed when working on my latest quilt because I kept changing threads to get the right colors in the blocks. Apparently, my machine only likes Superior So Fine thread. Perfect stitches every time with that thread. The other threads I tried cause all kinds of problems even though they look perfect on my sample square. They start off perfect on the quilt and then randomly change.

And the frustrating part is finding a solution. I recently FMQ'ed twice around a quilt border only to find out that the tension was fouled up and the bottom thread just laid there. Even though it was a Linus quilt, I just couldn't stand the way it looked so ripped out both stitching layers. Then I cleaned my machine, used the same needle and thread and did the same thing with perfect results. Haven't a clue of what happened but believe me,now I check my stitching many times during any process.

I have the same setup with sr2 frame but with brother pq1500. Had this similar problem and it was dirt on the track. When the wheel hit that dirt it hiccuped and then the stitch regulator skipped stitches. I now clean my rails and wheels after each quilt. Amazing how much dust and lint they collect.

I found out with my Jukie and stitch regulator that if I got in a hurry the stitches would get wonkey

When I had a set up like that, it was an encoder that was plugged in all the way. It took me a week of frustration to realize it.

Watson

Perhaps my prob 'could' be the stitch regulator. I did not turn it on when I basted the lap quilt, (I want to hand quilt it), and all went normally. Now I must put a practice sandwich on the frame and experiment.