Frequently, the thread breaks because the machine is mis-threaded or has been threaded out of order. You might try installing new needles (verify they are correct for the machine, are pushed all the way up and the flat side faces the right direction.
Remove all the thread from the machine. ALWAYS RAISE the presser foot Rethread from the beginning--BE SURE to thread each thread in the order specified (threading out of order will cause certain failure and frustration)! Confirm the thread path is correct for each! When threading from the thread tree down through the tension disk, give each thread an extra little tug to insure the thread is completely seated. The Lower Looper thread should finish by laying over the top of the Upper Looper!
If a thread breaks, it is usually less frustrating to just rethread everything from the beginning again. Trying to rethread a broken thread while the other threads are still intact works only 1% of the time that I try it.
While testing your machine, go slowly (as possible) and watch that needle thread. You may see it getting tighter and tighter before it breaks which means it is hanging up somewhere along the way... possibly looped around something, has a burr in the thread path, etc.
Answers & Comments
Frequently, the thread breaks because the machine is mis-threaded or has been threaded out of order. You might try installing new needles (verify they are correct for the machine, are pushed all the way up and the flat side faces the right direction.
Remove all the thread from the machine.
ALWAYS RAISE the presser foot
Rethread from the beginning--BE SURE to thread each thread in the order specified (threading out of order will cause certain failure and frustration)!
Confirm the thread path is correct for each!
When threading from the thread tree down through the tension disk, give each thread an extra little tug to insure the thread is completely seated.
The Lower Looper thread should finish by laying over the top of the Upper Looper!
If a thread breaks, it is usually less frustrating to just rethread everything from the beginning again. Trying to rethread a broken thread while the other threads are still intact works only 1% of the time that I try it.
While testing your machine, go slowly (as possible) and watch that needle thread. You may see it getting tighter and tighter before it breaks which means it is hanging up somewhere along the way... possibly looped around something, has a burr in the thread path, etc.
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Is there a burr on the needle!