Thread keeps knotting up under the fabric (bobbin area)

Knotting occurs when your top thread and bottom thread are not properly contacted or do not interact correctly. Whenever knotting happens, you will notice that thread will bunch underneath the fabric. You can try re-threading the upper part of your sewing machine, making sure the thread is passing through every single thread guide on its way to the needle. If you find yourself constantly adjusting the tension of your bobbin thread, check the bobbin itself. Plastic bobbins especially can wear, causing them to grow loose within the bobbin housing and making it difficult to maintain correct tension. Try switching to a new metal bobbin and see if that resolves your issue.

https://www.youtube.com/watch?v=1tgrAlQdX78
A: Looping on the underside, or back of the fabric, means the top tension is too loose compared to the bobbin tension, so the bobbin thread is pulling too much top thread underneath. By tightening the top tension, the loops will stop, but the added tension may cause breakage, especially with sensitive threads.
https://www.superiorthreads.com/education-how-to-adjust-bobbin-tension

The problem most likely is not the bobbin. The problem is the top thread. If thread is knotting, tangling under the fabric, it is a top thread problem.

Remove the top thread from the machine. ALWAYS RAISE the presser foot and rethread from the beginning.

If there are still thread clumps under the fabric, you will need to increase the top tension. (The extra thread appearing under the fabric is excess top thread hanging up under the fabric.) You may need to keep adjusting the top tension until both top & bobbin threads meet in the middle of the fabric.

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Are you getting knots under the fabric when you sew? If so, that is bird nesting (thread nesting) and is commonly a top thread issue. Most often the thread is not seated fully in the tension disk or the top tension setting is off.

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 tension at the midway point and then tweak it so the top and bobbin threads meet in the middle of the fabric.

Please check your fabric results. Is it the bobbin thread that is accumulating under the fabric, or is it really the top thread that is globbing and knotting under the fabric. Usually, thread mishaps under the fabric are the result of an issue with the top thread.

ALWAYS RAISE the presser foot when threading the upper thread. This releases the tension disks so the thread will seat properly. Use a brand new needle. Start out with the upper thread tension set midway between high & low numbers, although this can be tweaked.

If it is in fact the upper thread, then here are some suggestions:

Sewing Machine Thread Bunching Up Here Why

Troubleshooting Thread Nesting Sew Toot

try these suggestions
rethread the machine top and bobbin, using every thread guide
try a new needle--one for the fabric being sewed--make sure the needle is inserted correctly into the needle holder
make sure the thread does not come off the thread take up lever
try a different bobbin
make sure the bobbin is turned the right way in the bobbin case
clean under the needle plate and in the bobbin area for lint

Try these suggestions
1. Change the needle--use a needle that's for the fabric being sewed
2. Rethread the machine--top --make sure to use every thread guide
3. try a different bobbin--make sure bobbin is inserted correctly into the bobbin case, & make sure the bobbin is turned the correct way in the bobbin case
4. make sure the thread has not come off the thread take up lever
5. Clean under the needle plate & in the bobbin area for lint or threads

Could be a few things. Absolutely minutely check that the top thread is threaded properly. Otherwise, it could be: Old thread. incorrect thread for the material. wrong size or blunt needle. or incorrect tension on needle I had this problem and I was missing a part of threading even though I have been sewing for years. :)

Get out the manual and refer to the maintenance section for cleaning the machine.

Especially the bobbin area. You want to make sure the area around the bobbin case is free of lint and thread.

Use a new bobbin and re-thread the machine, with the presser foot UP.

Install a new needle, again according to the directions in the manual. Installed incorrectly can lead to mis-stitching.

If the problem persits, the timing may need adjusting.

This should be done by the sewing machine tech for Kenmore.

Sewusa.com has a guide for this in the repair section, but you could end up with more problems.

In 99% of all problems with "bird's nesting" or "knotting" it is an issue of the thread coming out of the take up lever (at threading guide #3) (from the spool; through the first thread guide at #1 down to #2 and up to # 3) when the thread comes out of the take up lever, the machine can not regulate the thread and it floods the machien with thread and wraps itself around the bobbin case. OR! Your tension is too loose. Raise it. Your machine should preform perfect at tension #4 unless you are using speciality threads or fabrics.

ALWAYS be in the habit of threading your machine with presser foot up so that while threading between paths 1 and 2 you are certain to have the thread pass throught the tension disks.

This will happen on a $50.00 machine or a $5,000 machine. The thread needs to be regulated.

USE GOOD THREAD!

Thanks,

Bonnie