HI, are you bring your bobbin thread up, to the top of your quilt ''sandwich''. I have to do this every time or I get knots and broken thread.

You may also want to change to a new needle.
Edit:
Hmmm -- didn't know about bringing the bobbin thread up to the top before beginning.

It prevents that first birds nest that comes when quilting. :thumbup: If I don't use a leader & ender I will use this when starting any seam. (I learned this here on the QB!)

One other thing........take out your bobbin, then unscrew the bobbin plate, and take it off, take out the bobbin case, and remove any fuzz or lint underneath the bobbin case with a brush. I have found that sometimes having a lot of lint under the bobbin case can affect my sewing. C9P

Make sure that the thread in the bottom is the same as the thread from the top.

Not only check tension but be sure you have a good sharp needle(schmetz- quilting needles really do a great job), bobbin is not overloaded, you are using a good quality thread- Coats and clark, sulky etc. Keep even pressure and tension with your hands and watch the fabric is not bunching up. If you are using a synthic or high loft batting that too can cause issues. Depending on the fabric- like sheets which tend to be a bit more touchy when sewing can cause thread jams. ry a few things then stop by a local quilt shop fr advice- when they see it they may be able to give better advice.

Hi,and welcome from Oklahoma. I think this happens a lot to some of. Don't dispair! Stop and check the tension on the bobbin. If thats ok then check how its threaded. Sometimes if you are doing fmq you may want to drop the feed dogs a bit. I sure hope this helps. Remember the Log Cabin is a very old favorite for a special reason. Its so beautiful and there are no quilt police. Just do what you can and enjoy your lovely quilt. marvel

Also-- and I just experienced this tonight-- take out your top thread, and re-thread it. I had some whacky tension problems that were caused by a mis-threaded top thread.