sharoney

If you have loops on the bottom, that means the bobbin tension is too tight or the needle tension is too loose.

RedGarnet222

Not to mention a needle with a burr or slightly bent could do this too. Try the cleaning, change the needle, and even change bobbins. Sometimes for some reason the machine decides it doesn't like the brand of thread you are using.
If all that fails, take her in for a servicing.

laralea

Thanks for all the suggestions. I tried the ones I hadn't thought of and finally got brave enough to turn the screw on the bobbin case and it's a lot better now - not perfect, but better enough to keep sewing. I'll get it serviced as soon as I can. The Bernina tension is supposed to be self adjusting and I've had very few tensions issues in the 25+ yrs. I've used the machine. I have other machines, but I prefer the Bernina for quilting. Thanks again - you are all awesome!!

scraphq

I have an 1130.sometimes the top thread doesn't get properly seated in the tension. There two slots ( for double needle sewing) Try threading through the other slot. Happens to me occasionally and switching slots fixes the problem. Never have to have service for this annoyance. Good luck!

dawsondelights

Try pushing your thread holder tight against the thread ,I had the same problem & thought the whole time it was the bobbin tension,boy was I wrong!Worked on mine.

laralea

I can't thank you enough! I'm sewing again on my beloved 1130 with a perfect stitch thanks to all your help. You saved me a whole bunch of hassle, time, and money.

Lilrain

especially if you use monofiliment thread

GABBYABBY

Looks like a tension problem. Try turning your
tension knob just a little at a time and see if
that helps.

Granny Quilter

probably tension like everyone says, also I have found when my Singer acts up, I always need to change needles. Last time I forgot about that and was thinking I needed a new machine. Anew needle, and it is working great again.