Upper thread breaking - Toyota TL-432DE Mechanical Sewing Machine

There are several common reasons for upper thread breakage.

Check that the needle/thread/fabric are compatible.
All About Needles

Remove the upper thread from the machine, install a brand new needle, ALWAYS RAISE the presser foot, and rethread from the beginning. Verify the thread path is correct. Set the upper tension to the midway point.

NMSU Checklist of Common Machine Troubles

Sewing Machine Problem 1 Thread Breakage

Sewing Machine Thread Keeps Breaking

Why Does My Thread Keep Breaking While Sew

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Usually when it stitches an inch or two and then breaks, the upper thread is mis-threaded.

Remove the upper thread and rethread from the beginning. ALWAYS RAISE the presser foot when threading the upper thread. Check to make sure the thread path is correct. If it is threaded incorrectly, the thread will frequently break.

Also check that the thread is not hanging up somewhere, sometimes it gets looped around something or it snags on the little slit on the thread spool or a rough spot.

If the upper thread tension is too tight, it will also break the thread. Make sure the tension disk is clean. If there is gunk or a piece of thread stuck in the tension disk, it could be interfering.

If the thread is fraying as it goes through the needle eye, then there is probably an incompatibility of the needle, thread, fabric.

All About Needles

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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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Check thread routing

Upper thread breaking is usually a sign of incorrect threading or tension too tight, although there are other possible problems:

Industrial Garment Printers Sewing Machines

When threading the upper thread, be sure to ALWAYS RAISE the presser foot so the thread will seat properly in the tension disks. Avoid old thread or bargain bin thread. If the thread is fraying and breaking at or near the needle eye, then try a different type of needle with a larger thread groove that will protect the thread from fraying on rough fabric. Also, check that the thread is not hanging up on something, ie the slit on the side of the spool where the thread tail is stored.

Sewing Machine Problem 1 Thread Breakage

Sewing Machine Thread Keeps Breaking

NMSU Checklist of Common Machine Troubles

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Have you tried loosening the upper tension? Remove the upper thread, RAISE the presser foot and rethread from the beginning (make sure it follows the correct thread pathway). Sometimes the upper thread jumps out of a thread guide or wraps around something. Or try a different brand of thread? Avoid old or bargain bin threads--use good quality thread. Could also be the incorrect needle for the thread/fabric, ie thread too large for the needle eye.

Sewing Machine Thread Keeps Breaking

NMSU Checklist of Common Machine Troubles

Why Does My Thread Keep Breaking While Sew

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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.

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

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Be sure to RAISE the presser foot BEFORE threading the upper thread. This releases the tension disk so the thread can seat properly. If upper thread is breaking soon after beginning to sew, it usually is because the upper tension is too tight. Try loosening it and re-testing. The upper and lower threads should meet in the middle of the fabric.

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Check the spindle the thread is mounted on and see if it\'s wrapped around it. Sometimes thread will catch and wrap around the spool spindle and break.

Check thread guides to be sure there are no nicks that might be catching the thread or damaging it.



Replace the needle.. a burr in the eye can cause upper thread to break. Needles should be replaced often, modern fibres can be hard on them, they get dull and that\'s no help for anything either.



Make sure the thread spool is mounted on the spindle with the thread coming off as directed in the manual. Some machines only work when the thread feeds in the right direction from the spool.



It can also be a tension issue.. tight upper tension or tight bobbin tension. Bobbin tension may be adjustable manually, but it\'s pretty rare for it be a problem. Upper tension, I don\'t know. I\'ve yet to get into computer machines so am not familiar with how they set upper tension.



But the mechanism that produces the tension can wear out or break and need replacement.

I ended up switching the spools of thread around. Apparently, even though I had purchased good quality threads, one of the spools was wound in a way that made the thread loop and twist around. So I put the offending spool of thread through one of the needles and put the needle thread on the upper looper. That seems to be working. By the way, BabyLoc was very unhelpful dealing with this problem.  Thank you!