Top thread snapping during quilting

When the thread is fraying at the needle eye, it sometimes means the thread is being held back somewhere in the thread path. Remove the top thread. ALWAYS RAISE the presser foot and rethread. Verify the thread path is correct. Check the tension. If it is too tight, the tensioner is not allowing the thread to advance. (When you raise the presser foot, are you able to pull the top thread?) Try changing thread brands. Some threads and machines just do not get along. AVOID old or bargain bin threads. If you are stitching coarse, abrasive fabric, it can cause thread to fray and break.

Tension for stitching a quilt sandwich is tricky. It helps if you use the same color for top and bobbin thread,. If your quilting thread is not the same weight (either heavier or lighter) than thread used for regular sewing, then the bobbin tension may need to be adjusted. My quilting thread is lighter weight so I have a separate bobbin case whos tension has been adjusted specifically for quilting. The goal is have both threads meet in the middle of the sandwich. If the top thread is showing under the sandwich, you probably need to tighten the top tension so it will pull the bobbin thread up into the sandwich. Do the reverse if the bobbin thread shows on top.

It may also make a difference by changing the type and size needle. I tend to prefer a top-stitch needle. An embroidery or microtex may also work for you.

Machine Quilting Thread and Tension

Tension troubles on your quilting machine Try these tricks

5 Free Motion Quilting Problems and How to Fix Them

Quilting is a bit more finicky than regular sewing. Be sure to ALWAYS RAISE the presser foot when threading the top thread. FWIW, I use a separate bobbin case for FMQ that I have tightened the tension to keep the bobbin thread from coming to the top of the sandwich, but I tend to use a finer thread for quilting so adjusting the bobbin takes care of it. In your case, however, it sounds like the top thread is staying under the fabric. I would try tightening the top tension. Also, install a brand new needle--a top stitch, embroidery, or microtex needle seem to work well for me. Test well on a sandwich made of the same fabric and batting and get it adjusted well before sewing on your quilt. Sometimes sewing speed will affect stitches under the fabric, or even on top.

5 Free Motion Quilting Problems and How to Fix Them

Correcting Sewing Machine Tension for Free Motion Quilting NQC

LOOPS Tension or Speed

https://www.generations-quilt-patterns.com/machine-quilting-thread.html

https://www.generations-quilt-patterns.com/sewing-machine-tension.html

https://www.generations-quilt-patterns.com/machine-quilting-tension-problems.html

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Depends what exactly is happening with your machine, not stitching? fabric not moving? pulling up polyester??? puckering?? tension issues?? Verify it is threaded correctly. It could be an incompatibility of the needle/thread/fabric sandwich. Be sure to use a brand new sharp needle. You may need a walking foot. If it is not a good quality of polyester batting, it could cause issues. Poor quality thread. Tension not adjusted. Etc...

You can probably narrow down the problem by trying different batting, different fabric, different needles, and different thread on scrap fabric sandwiches.

make sure that the thread tensions are correct for the thickness of material
remember that only the bottom foot walks and draws the material through so it may need a help and be pulled as it sews.
I find that women in sewing shops just love to talk about problems and how they can help so find a shop and discuss any problems with them

Could be several things.

First, install a brand new needle, perhaps a top-stitch needle will work better because it has a groove in the shaft that protects the thread. Make sure the needle is the appropriate size for the thread you are using--a needle eye that is too small will cause the thread to hang or shred. When the needle penetrates the sandwich, the top thread forms a loop. If the eye is too small, the thread will not come back up through the sandwich, leaving a loop under the fabric.

Remove the top thread from the machine.
ALWAYS RAISE the presser foot and rethread from the beginning.
Set the top tension to the midway point and retest your machine on a quilt sandwich made of the same fabric layers as your project.. Tension problems are more evident when sewing multiple layers of fabric, so tweak the tension until the top and bobbin threads meet in the middle of the sandwich.

I don't believe you will have to adjust the bobbin tension, but in case you do, be very careful. Mark the tension screw setting FIRST so you can reverse any changes you make. Bobbin adjustments are made in very SMALL increments. Because I tend to use a lighter weight thread for my quilting, I have a specific bobbin case that is adjusted for my quilt thread and I keep my other bobbin for regular sewing. Then I don't have to keep adjusting the bobbin tension when going from sewing a quilt to something else.

Some machines do better with certain brands of threads than others.

Adjusting Sewing Machine Tension to Prevent Problems

12 wt thread generally will not work well in the bobbin...


"Aurifil 12wt Thread
Aurifil 12 wt thread is ideal for hand quilting, big stitch hand quilting and machine quilting. 12 weight thread creates a more defined and often primitive look. It's great for designs that use a longer stitch length if using a machine. When machine quilting with 12 wt thread, use 40 wt in the bobbin, increase your stitch length, lower your tension, use Topstitch size 90 needles and stitch slowly."

from what you said about the bobbin thread continues to break
check for burrs in the following area--even the smallest burr can cause problems
bobbin
bobbin case
needle plate
needle could be damaged
or bad thread

Check the bobbin tension too. It could be too tight. Make sure you are using the right size needle for the material as well. Sheer, thin fabric needs a smaller needle, thicker material requires bigger needles. Bobbin tension is the typical problem as most think to adjust the top tension but don't check the bobbin tension.

Is your quilt peices cotton? Cotton shouldn't cause as much trouble sewing along the edge but don't use too long of a stitch length else it will seem to gather up. Puckering side to side however is a tension problem usually. With sheerer fabrics that cause a problem sometimes you can put thin paper underneath, sew through both and then pull the paper off after sewing. (thin like the iron on type interfacing type fabric but like paper).

Sounds like the feed is your problem. Most likely you need a different foot. Check the bottom of the foot - it should be quite smooth to allow the dog feed to move the denser layers along smoothly. Hope this helps.