The wiper is striking the upper looper breaking the thread

Which thread, needle threads, or looper threads?
If looper threads, be sure to unthread both loopers and retread in correct order, 1;2;3;4:
be sure upper looper is threaded before lower looper

Third thread--is that the upper looper? Remove all the threads from the machine. Clip them below the thread tree, RAISE the presser foot, and then pull all 4 threads down through the needle. (Never Pull Up!!)

ALWAYS RAISE the presser foot.
Rethread beginning with the Upper Looper, then Lower Looper, then the needles. Be sure to ALWAYS thread in this order!! (On most newer machines, when threading the Lower Looper, always finish with the Lower Looper "draped" over the top of the Upper Looper.)

If a thread breaks, remove the threads and start over from the beginning as trying to fish a thread through the existing threads very SELDOM works.

Verify each thread path is correct.

When threading each thread and to insure the threads are seated in the tensioners, give each thread an extra little tug when going through the tension disk.

Be sure to oil your machine frequently to keep it operating smoothly!

Make It Handmade Threading Your Serger or Overlocker

Serger threads Threads Magazine Gatherings Forum Sewing Questions Answers

Assuming this is a serger. The second thread from the right would be the lower looper. Nine times out of ten, when the looper thread breaks, it's because it is threaded incorrectly or the tension is set too high.

It is generally recommended that when a thread (especially a looper thread) breaks on a serger, you should remove all the threads and start over from the beginning (yep, that sounds painful but it is better to just bite the bullet and just do it rather than fighting it and never getting it threaded right). Make sure the presser foot is raised throughout the threading process, give each thread an extra tug when going through the tension disk to insure it is seated in the disk properly, follow the threading order (usually upper looper first, then lower looper) and the thread pathway is correct for each thread (no guides are skipped and thread is not wrapped around something). The last step of the lower looper threading is to make sure the lower looper thread drapes over the upper looper before being pulled under the presser foot and toward the back of the machine.

Set the tensions to the midway point between high & low numbers before testing.

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try a new needles
check for burrs
make sure the thread is not caught anywhere

Typically a serger is threaded... upper looper(s) Lower looper(s) Needles from right to left. Anything else will cause you problems. If you break a thread... remove all other threads and begin again at the upper loopers.

Try rethreading all the threads making sure you thread in the recommended order: Upper Looper first, Lower Looper second with the tail Crossing Over the Upper Looper as the last step, then thread the needles.

Then it's one of two things. First try setting your lower looper tension on 3 and see if that works. If not set it back on 4 and cut ALL your threads and re-thread the machine STARTING with the UPPER looper, then the lower looper, then the right needle, last the left needle if you're sewing a 4 thread overlock stitch. Make sure the threads aren't twisted in the thread guide. Make sure the lower looper thread is OVER the elbow on the upper looper and over the upper looper thread. Let me know if this works. We'll work until we get it fixed!

I have found with any serger I have used that you have to cut the looper (bottom) threads before re threading the needle threads. You then rethread the loopers.
If you don't do this, the needle threads keep breaking. Hope this helps.

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!

I had the same problem with the blue thread- it would sew and inch then pop- mine worked wihtout breaking after I re threaded in this order: green, blue, red then yellow