The upper thread tension keeps breaking the thread, no matter how low I set the tension. How do I fix it?

If bobbin thread is exposed on the top then either the upper thread tension is too high or the bobbin tension is too low. Use the same type of thread for top/bottom.

See vide, how to test tension;

https://m.youtube.com/watch?v=YF7EOCvpHLg&feature=youtu.be

Most likely, your tension is too tight. First thing, unthread the machine. RAISE the presser foot and rethread from the beginning. The standard initial tension setting is the midway point between high & low number, HOWEVER, that will probably need to be tweaked as machines vary.

The tension is correct when upper and bobbin threads meet in the middle of the fabric. If the thread continues to break, then there may be a snag somewhere that is catching the thread and breaking it. Also, check that the thread notch on the spool is not catching the thread. Be sure your needle is compatible with the thread, ie the thread is too thick for the needle eye.

Understanding Thread Tension Threads

Sewing Lesson 10 How to Fix Tension on Your Sewing Machine

How to Adjust Sewing Machine Tension on Craftsy

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Thread breakage could occur for several reasons.

First, try a brand new needle.

Second, use only good quality thread--NOT old thread or bargain bin varieties.

Third, when threading the upper thread, be sure to ALWAYS RAISE the presser foot throughout the threading process.

Verify that the thread path is correct (consult the owner's manual). Incorrect threading will usually break the thread.

Check that the upper thread tension is set at the midway point between the high & low numbers.

Why Does My Top Thread Keep Breaking Sewing Machine

Sewing Machine Problem 1 Thread Breakage

Sewing Machine Thread Keeps Breaking

NMSU Checklist of Common Machine Troubles

Why Does My Thread Keep Breaking While Sew

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Usually thread breakage is a result of incorrect threading or the thread tension set too tight.

Install a brand new needle.

Remove the upper thread. RAISE the presser foot and rethread from the beginning (verify the threading sequence is correct).

Check that the tension is set at the midway point between the high and low numbers.

Retest. If still breaking, there are other less common problems (thread/needle incompatibility, burrs or knicks catching the thread, etc) that may be the cause. Check the following web sites:

Sewing Machine Thread Keeps Breaking

Why is my thread breaking

Sewing Machine Problem 1 Thread Breakage

Factory standard tension for upper thread is the midway point between the high and low number. However, that tension dial is meant to be used for tweaking tension. Generally, tweaking is required whenever the type of fabric, needle, or thread are changed, ie thicker fabric like denim should have a different upper tension setting than fine chiffon. To be successful with tension settings, one must become comfortable adjusting the upper tension.

NOTE: Accurate tension is achieved when the upper thread and bobbin thread meet in the middle of the fabric.
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Understanding Bobbin Tension


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The most common cause of upper thread breakage is incorrect threading. Remove all the thread, install a brand new needle, RAISE the presser foot, and then rethread from the beginning. (Verify with the owner's manual that the threading process is correct.) The other thing to check is the upper tension setting. The factory standard setting is usually the halfway point between the high and low numbers. Tweak the upper tension to achieve correct tension. Correct tension is when the upper thread and bobbin thread meet in the middle of the fabric. The upper tension is meant to be the most common method of tweaking tension. As such, a sewist should become comfortable with tweaking the upper tension.

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Install a brand new needle. Make sure you are using thread and needle that are compatible with the fabric you are sewing.

Change the type of thread you are using. Old or bargain bin threads will frequently cause problems.

Clean the tension disks to make sure there is nothing stuck that is preventing the thread from feeding.

Remove all the thread and re-thread from the beginning. FIRST raise the presser foot so the tension disks will allow the thread to seat properly. (Consult your owner's manual.) Make sure you are threading everything in the proper sequence and not missing any steps.

Set the upper tension at the halfway point between the high and low number.

Stitch a test on a piece of your scrap fabric from your project.

The ideal tension is when the upper thread and bobbin thread meet in the middle of the fabric. If the bobbin thread is appearing at the top of the fabric, your upper tension is too tight and needs to be loosened. If the upper thread is appearing under the fabric or forming a loopy mess, the upper thread is too loose.

Keep adjusting and testing until the tension appears correct.

If the thread continues to break, then there may be a burr that is catching the thread and breaking it. Or the timing could be off. Take it for service.

http://www.schmetzneedles.com/all-about-needles/

http://www.sewingandcraftcorner.com/why-does-my-thread-keep-breaking-while-i-sew/

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one of three issues: top tension too tight, bottom tension too tight, needle timing off.

***Upper tension setting
*** Put the pressure foot up.
***As you are threading give little tugs to check for snags. Snags must be fixed.
***When finished threading (not the needle) put the pressure foot down.
***Check the tension by starting at zero and increase the tension slowly and give small tugs to see if the tension is rising. (This is all done without the needle being threaded)
***When you feel comfortable this is working then thread the needle and set the tension at four.
***Set the bobbin tension. Attachment gives instructions.
Now that all of the tension has been set you can try for

the needle thread tension is wrong
bunching up under the material indicates that it is too loose