As I am sewing the tension seems to tighten up until the thread breaks. It will sew fine the suddenly it starts to knock and I know the top thread will break any second. I am quilting free hand. I have finished about 1/3rd of my quilt and this just started. However for quite a while I have been having trouble filling the bobbin. It starts out fine but about half way it binds up and will completely stop. Since this seems to be tension related I thought both problems might be related.

I am not sure about this particular machine but in most machines there will be a nob on the front loose low numbers like 0 1 -2 work well on number 3. If the nob is not on the front check and see if it is on the side.

Install a brand new needle (make sure it is compatible with the thread and fabric). Remove the top thread from the machine. ALWAYS RAISE the presser foot and rethread from the beginning. Verify the thread path is correct. Set the top tension to the midway point and retest your machine. Tweak the top tension until the top and bobbin threads meet in the middle of the fabric.

AVOID old or bargain bin thread.

http://www.servicethread.com/blog/stop-industrial-sewing-thread-breaks

Sewing Machine Thread Keeps Breaking

https://www.sewhere.com/why-is-my-thread-breaking-how-to-avoid-thread-breakage-at-your-sewing-machine

Why is my thread breaking

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Bobbin tension is one of the biggest problems most sewing machine operators have. Check information sent for assistance on this.

Ihave a brother industrial machine that used to break the the thread because the tension of the thread was too high.There is a little spring loaded tensioner ontop of the machine thad a nut that could be screwed down to increase tension. As this was a little too tight as Isewed and the thread was pulled around the centre post it would tighten up and the thread would snap.
I think that you must check to ensure that the path of the thread on top of the machine is one that does not introduce too much friction. any tension adjusters should be experimented with
Good Luck

The needle thread breaks
1. the needle thread is not threaded properly
2. The needle thread tension is to tight
3. The needle is bent or blunt
4. The needle is incorrectly inserted
5. The needle thread & the bobbin thread are not set under the presser foot when starting to sew
6. the threads were not drawn to the rear after sewing
7. The thread is either to heavy or to fine for the needle
8. The needle is not the correct one for the fabric
9. Rethread the machine

Hi Lou! This sounds like a tension problem--the tension on the top thread is too loose. Try using different color threads on the top and bobbin, then carefully rethread everything. Stitch a couple of inches and check the underside. If the top stitches look fine and the bottom ones are loose and loopy, and with the pressure foot down, tighten the tension. Move the knob or dial (whichever you have) just a little bit. Sew a couple of inches more, and recheck. Continue to sew and recheck, gradually tightening the tension, until you see little if any bobbin thread on the top or top thread on the underside of the fabric.

Let me know if this helps, ok?


Robbie

This is usually caused by the machine being out of sync. The first thing I would try is a brand new needle. Even a slightly bent needle can cause this problem. Make sure the needle is in correctly and tight. Next make sure you treaded the machine correctly, making sure that thread goes into the top tension properly. The top tension should be calibrated to be in the middle. I would slowly turn the handle making sure the stitch looks proper. From there try tightening or loosening the tension until the loops on the underside start to get smaller until they look tight but not too tight or you'll start breaking the top thread.
I would use a standard 14 needle with some standard medium weight cotton to calibrate the unit.
Hope this helps. Let me know your results

Use a bigger spool stopper to keep the thread from catching in the **** on the thread spool.
sewman7

Well, I could have written this. I bought a used model from a repairman about a year ago. I have a Model 537FA and I'm going to throw it out in the rain leftover from TS Fay if I don't find some kind of help. :) I'm thinking it's a tension issue, but I can't seem to find a fix.

Does your tension on your top thread sometimes tighten to impossible to move in the middle of sewing. I know that mine does this and it causes the top thread to break. I don't know what's causing the bobbin mess.

Maybe someone will help us? Please!