Thread on brother pe770 getting tangled up in bobbin casing

It would probably be best to just buy a new bobbin case for your machine. There are some very intricate settings for a bobbin case to work and unless you have the technical expertise and tools, it most likely will not perform satisfactorily. (FWIW, many sewists, me included, have more than one bobbin case for a machine because each is set up for different weights of bobbin thread. For the most part, they are not that expensive.)


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Remove all thread (including bobbin) and and rethread according to manual. Usually it is the top thread that has jumped from with the path.

sounds like a needle problem, make sure the needle is the right size, try lowering it (loosen the needle screw and drop it down just a tiny)

if you had a "Birds nest" when sewing, you still have some lose threads in the bobbin case and the case isn't installed correctly.

The motor locked up because the thread is tangled.
Solution:
Remove the tangled thread before continuing the operation.
Clean the bobbin case to remove the tangled thread.
After cleaning the bobbin case, insert the bobbin case properly.
If the needle is bent or broken, replace the needle.
Then, thread the upper thread properly, and continue the operation.

Several things to check. Did the needle break and jam in the bottom? Is the needle bent or did it jam in the bobbin area? I had a 'knot' of thread build up on the bottom and it hooked itself into the metal clip on the bobbin so that the needle couldn't raise. If thread jams in the bottom cut the threads until you can free the hoop and material. Check the bobbin for pieces of thread and fuzz. Check to see if the bobbin case or the throat plate is scratched or bent. If you are stitching Free Standing Lace on this machine or a piece with over 20,000 stitches I recommend starting with a new full bobbin and a new needle. As you get toward the bottom of the bobbin, thread seems to have a high likelihood of tangling or looping and will cause a jam which means the handwheel locks.

The motor locked up because the thread is tangled. Remove the tangled thread before continuing the operation.Clean the bobbin case to remove the tangled thread. After cleaning the bobbin case, insert the bobbin case properly. If the needle is bent or broken, replace the needle.Then, thread the upper thread properly, and continue the operation.
brother sewing machine

You might have a bad bobbin case. check for any burrs on the bobbin case, and replace it if so.

In my Brother CE-4000, it appears as though the feed dogs (which you can change to a higher position or a lower position) are allowing the bobbin case to spin all the way around and then the needle hits the bobbin case. When the feed dogs are in the lowest position, the bobbin case does not spin all the way around when the needle moves up and down (and therefore the needle does not get stuck in the bobbin case. I am wondering if this is a problem with the feed dogs/case?

You need to sew the first stitch slowly. Lower the needle by hand and take up carefully. Pull the needle thread up and the bobbin thread should be caught in the formed loop and come with it. Pull them both to the back of the machine and sew.