My sewing thread keeps breaking, tension is on 4, but even on 2 it still breaks. Kind of fabric doesn't make any difference and I have changed needle.

Install a brand new needle (make sure it is compatible with the thread and fabric). Remove the top thread from the machine. ALWAYS RAISE the presser foot and rethread from the beginning. Verify the thread path is correct. Set the top tension to the midway point and retest your machine. Tweak the top tension until the top and bobbin threads meet in the middle of the fabric.

AVOID old or bargain bin thread.

http://www.servicethread.com/blog/stop-industrial-sewing-thread-breaks

Sewing Machine Thread Keeps Breaking

https://www.sewhere.com/why-is-my-thread-breaking-how-to-avoid-thread-breakage-at-your-sewing-machine

Why is my thread breaking

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Several possibilities. It could be the needle, the tension too tight, mis-threading, the thread weight, brand, poor quality, or fabric incompatibility with needle & thread.

Sewing Machine Problem 1 Thread Breakage

Sewing Machine Thread Keeps Breaking

Why Does My Thread Keep Breaking While Sew

All About Needles

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1. While threading put the foot up.
2. Give gentle tugs along the way. It should be without feeling any hangups.
3. Wherever the hangup is you must correct. Usually at the tension disc.
4 Sometimes the tension disc is tightening more than the indicator says. It should be about four. You can lower this tension setting until the stitch looks good.
5. You may have to take the tension assembly off and clean it thoroughly and sand any rusted spots.

Serger thread breaks
1. Is the serger threaded correctly?
2. Is the needles inserted correctly?
3. Is one of the needles bent or damaged?
4. Is the tension adjusted too tightly?
5. Is the tension adjusted to accommodate thickness of thread being used?
6. Are you using inferior quality thread?
7. Is the thread feeding of the cone/spool freely?
8. Is the needle size correct for the type of fabric being used?
9. Are the needles being used the correct one for the serger?

adjust the top thread tension one number or letter higher at a time
and sew on a scrap piece of fabric till the stitches look normal

The needle thread breaks
1. the needle thread is not threaded properly
2. The needle thread tension is to tight
3. The needle is bent or blunt
4. The needle is incorrectly inserted
5. The needle thread & the bobbin thread are not set under the presser foot when starting to sew
6. the threads were not drawn to the rear after sewing
7. The thread is either to heavy or to fine for the needle

Needle breaks
1.the needle is damaged
2.the needle is not correctly inserted
3.wrong size needle for the fabric
4.the wrong foot is attached
5.the needle clamp screw is loose
6. Top tension is too tight
7. Machine could be out of time


The needle thread breaks

1. the needle thread is not threaded properly

2. The needle thread tension is to tight

3. The needle is bent or blunt

4. The needle is incorrectly inserted

5. The needle thread & the bobbin thread are not set under the presser foot when starting to sew

6. the threads were not drawn to the rear after sewing

7. The thread is either to heavy or to fine for the needle

Needle breaks
1.the needle is damaged
2.the needle is not correctly inserted
3.wrong size needle for the fabric
4.the wrong foot is attached
5.the needle clamp screw is loose
6. Top tension is too tight--loosen off one letter or number till the stitch
looks normal
7.make sure that every thread guide is used when winding the
bobbin,, so that the bobbin will wind tightly, if this doesn't help,,
then it's possible that the bobbin winder needs adjustment,, it needs
to be taken to a sewing machine shop

Hello

Primary causes of upper thread breakage:


-- misthreading: pull all the thread off and thread again, using the manual, step by step. Read each step aloud before you do it. (sounds dumb, but helps.) (And make sure you thread the takeup lever!)

-- thread has wrapped itself around a thread guide or spool pin from one of the breaks. Take the spool off the machine before rethreading.

-- bad or damaged needle. Replace with the right size for the fabric, turned correctly (backwards needles skip stitches)

-- dirty machine, especially in the bobbin case area: review cleaning instructions and do it, using brush and vacuum only

-- bad/cheap thread: should not be slubby or break easy. Try another spool.

-- top thread tension too tight. 4 is normal for most fabrics, most stitches.

Tips;

1) do a light cleaning (brush and vacuum) every day you sit down to sew.

2) replace the needle if you hear it hit metal, if you've got a really bad thread jam, if you see it deflect as you sew (for instance, sewing over the side seam on jeans when hemming). Replace every 3-8 hours of actual stitching time anyhow.

3) buy good quality thread

4) when your machine isn't sewing right, stop; take all the thread off of/out of the machine (bobbin out of bobbin case, spool off spool pin) and give it a quick cleaning. Rethread from scratch, carefully. If that doesn't fix it, do it again, then replace needle and rethread one more time, manual in hand (yah, even if you've threaded it 8 million times before). #4 is curative about 98% of the time. The other 2% often requires professional attention.

Good day!

please try this simple tips:

Good day!

A sewing machine operator can often help themselves when their machine does not operate properly.
Here are some simple instructions, which if properly used can save time and mechanics service calls.
TROUBLE;UPPER THREAD KEEPS BREAKING;
This could be trouble;================Do this;
1.Top tension to tight================loosen tension 1 turn
2.Machine improperly threaded=========check threading
3.Thread twisted on guide post========"
4.Thread twisted out of tension======="
5.Take up spring bent or broken=======Check action of spring
6.Thread jumped off pull off finger===Check threading
7.Needle bent or burred===============new needle
8.Bad cone of thread==================try another cone
TROUBLE;LOWER THREAD KEEPS BREAKING;
1.Bobbin tensionspring to tight=======Loosen tension slightly
2.Bobbin threaded wrong===============check threading
3.Bobbin wound to tight or uneven=====try new bobbin
4.lint or thread on bobbin case=======clean inside case
5.Lint or thread inside hook==========clean inside hook
6.Bobbin case nicked bent or burred===check/change case
TROUBLE;MACHINE STARTED SKIPPING STITCHES;
1.Needle bent or burred===============change
2.Needle set in crooked===============Check
3.Thread jumped off take up spring====check threading
4.Thread jumped off pull off finger===check threading
TROUBLE STITCHES SHOWING LOOPS;
1.Forming loops on top of cloth=======Tighten bobbin tension
======================================or loosen top tension.
2.forming loops on bottom of cloth====Tighten top tension
3.Bobbin placed in case incorrectly===remove and replace
4.Bobbin thread slipped from under====check threading of
tension===============================bobbin case
5.Lint or thread in top tension=======clean between tension discs


Thank you and good luck.

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