Out of nowhere, after working fine for weeks, the bobbin thread started breaking, and then stopped "wrapping" properly around the outside of the bobbin while I sewed. It keeps jamming to where I can't get the needle to go up *or* down, and when I open the area where the bobbin is there are multiple threads that need to be cut and are going up through the plate. What's going on?

increase the needle thread tension up a bit as it is too loose to pull the bobbin thread up properly
keep adjusting until both threads are at the middle of the materials being sewn

You don't mention which thread is breaking. Am assuming top thread.

Install a brand new needle (old needle may be damaged).
Use good quality thread or try changing the brand of thread you are using (some brands may work better than others).
Remove the upper thread. RAISE the presser foot and rethread from the beginning. Verify it is threaded correctly (consult the owner's manual).
Set the upper tension at the midway point between high & low numbers.
Verify the bobbin is inserted in the bobbin case properly and the bobbin case is threaded correctly.
Retest.

If thread is still breaking, there is a possible burr or nick somewhere that is catching the thread and breaking it. You can try wrapping your finger with an old piece of hosiery (or something similar) and rubbing around the needleplate, hook, shuttle. If it catches the fabric, then you know where the damage is. If it is a small blemish, you can sometimes buff it using very fine sanding paper or fine emery board to smooth it. (Be gentle and do not sand too much.) If the damage is large, perhaps it would be better to purchase a new part.

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It sounds like the lower shuttle is out of place. You should be able to take out the bobbin case and unlatch the shuttle. It will probably be in 2 pieces. Clean out the dust behind it and replace the shuttle pieces. You may have to fiddle with it a little to get them back in place. Then you can test it by manually turning the wheel. Make sure the bobbin is placed into the bobbin case and that the bobbin turns in the direction that you pull the thread.

Good luck.

relax and start over. make sure the bobbin thread is alright and the bobbin is put back in properly and try again.

It is likely that you have some thread wrapped around parts in the bobbin area. open up the bobbin area and carefully examine for threads and remove them.

Hello Crystal, I also have had problems in the past with drop-in bobbins . I had to experiment with different model bobbins . The cause I found was due to the bobbin was not tall enough in the drop-in bobbin case. When sewing , the bobbin would rock in the bobbin case and the top thread would get caught on the bobbin instead of going over the top of the bobbin, causing the rats nest that you described. I would recommend finding a taller bobbin to fit in the bobbin case. There are about five different bobbins that will fit in there, but only one that will work properly. Knowing the exact model number of your machine would be a great help to finding the correct bobbin.

Mine did same thing,was told to wrap twice around the silver know where you normally wrap twice,make sure bobbin is all the way down.dont forget you start threading as if you were going to for top thread go thru first hook then over to silver know,but twice.hope this helps did me

Make sure there is no fluff/lint within the bobbin case causing the bobbin to stand proud. Pressure from the bobbin thread can sometimes stretch the bobbin itself.. replace the bobbin with a brand new one. Double check your threading be removing all thread and starting from scratch.

Clean out the bobbin area.

Thread the machine with the presser foot up. This opens the tension so the thread can enter. Threading with the foot down closes the tension and the thread cannot enter as it should. When you sew, the top thread is loose and cannot properly connect with the bobbin thread to form a tight stitch. The stitching does not hold and pulls right out.

Thread breakage - top thread? Check the thread spool to be sure there aren't any nicks to catch the thread.

When the thread breaks, check the spool pin to see if the thread is unwinding too fast and wrapping around the pin. Thread nets can help stop this. You can find them at sewing machine dealers.

It sounds as though the thread is jumping out of the tension assembly. The next time this happens, do not raise the presser foot before you do the following.Cut the thread above the needle and pull on it.If it is working properly there will be tension on it.If it is not working properly, the thread will pull through very easily.If the thread is coming out of the tension , either it isn't threaded correctly or you may need to wrap the thread around the bobbin winder guide to keep it from coming out.If you wrap it around the bobbin winder guide reduce the tension to around 2 , 3 or even less.
Hope this helps.
sewman7