Threading the machine properly - Yamata FY811 Mechanical Sewing Machine

needle thread tension is not adjusted up properly tighten the setting until you have resistance when you pull the thread to thread the needle

bunching of thread under the material is an indication of insufficient tension of the needle thread
increase the needle tension until the threads meet at the center of the materialbeing sewn

Make sure you have threaded the machine properly--which usually involves removing the thread and rethread from the beginning. Make sure to RAISE the presser foot before threading the upper thread. Check that the bobbin is loaded in the bobbin case and it is threaded properly.

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Consult the owner's manual and make sure you are threading the machine properly. Remove all the thread. Make sure the needle is installed correctly. Always RAISE the presser foot BEFORE threading the upper thread so the tension disks will allow the thread to seat properly. Rethread from the beginning. Bird nesting is usually a result of the upper tension being set too loose or the thread not feeding through the tension disk properly.

Use needle & thread that are compatible with each other and the fabric being sewn, ie is the thread too heavy for the needle?

Sewing Machine Thread Bunching Up Here Why

All About Needles

Also may help to bring the bobbin thread up to the top of the fabric and holding both threads when taking the first few stitches.

How and Why to Bring up the Bobbin Thread

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You are not exactly threading the machine when you wind the bobbin. So follow the directions for winding the bobbin, make sure the thread fits under the little revolving wheel, and make sure that the stitch part of the machine is disengaged.

I could be as simple as threading the machine with the presser foot up.

When the foot is up, the tension opens and accepts the thread. Foot down and thread cannot enter as it should.

Out of control upper thread can look like a bobbin tension problem.

Get a manual for your machine so you know how to properly thread the machine - you need to be sure the thread goes through the guides in proper sequence and - ALWAYS thread a sewing machine with the presser foot up.

You need to be sure the bobbin thread is feeding in the correct direction from the bobbin spool and through the correct guides.

Check the needle to see if it is installed correctly and is not bent.

Most sewing machine needles are installed with the flat side toward the back of the machine.

After proper threading and bobbin feeding, hold onto the top thread tail and lower the needle down and back up to pull up the bobbin thread.

Take both thread ends under the presser foot and to the back of the machine.

You did not provide the make and model of your machine so I can only suggest if you do not have a manual, search the Internet. Singer and Brother have downloads. Sewusa has many brands/models.

I don't know how to adjust tensions but make sure you have the machine threaded properly and the needle oriented correctly. When I did not have mine threaded properly that is what the bobbin thread did - just stayed on top of the material and did not get pulled into the fabric.

Be sure to check that the machine is threaded properly into the needle. Also look at the instruction book to be sure you have the bobbin inserted corectly and that the thread is place properly (threaded correctly) in the bobbin area. Some machines have a diagram on the machine, but if you do not sew frequently; it's easy to mis-thread the bobbin. Did your bobbin thread wind properly onto the bobbin (not loose or loopy). That too, can be a problem. Best of luck. Susan

Double check that your needle is the proper one for your machine, and that it is in properly. It sounds like it is not picking up the thread properly. Tension problems usually have more to do with threading, thread or needle problems than with bobbin problems. Also check your bobbin is unwinding in the proper direction for your machine. Most machines unwind the bobbin thread, turning clockwise. Set your screw back to the factory settings, and give the machine a good cleaning as well. Lint can cause this to happen as well, if it builds up enough to interfere with the needle and the hook action. Double check that your upper thread is threaded properly as well. I suspect your needle is in backwards however.