Tangle in bobbin area, stuck needle

Question

"tangled in the bobbin area. I would only be able to sew about an inch of fabric before the problem started. The needle would get stuck and not move...and I would literally have to get needle nose pliers out to unsnarl the thread under the needle...what a mess! "I have the same problem. Have a Juki DDL-8700 and sewing heavy felt.  On the backstitch the bobbin gets caught and snarls a tangle in the bobbin case.  Now, the needle won't move despite a clean up.  Is there a way to remove the casing?  How can I avoid this problem.  Thank you!