I have threaded and re-threaded this machine. the threaded keeps breaking and it is driving me nuts! I have followed the threading instructions and adjusted the tensioner with no help

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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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

Here are a few sites that may be helpful in diagnosing your problem:

NUMBER ONE SUGGESTION--install a brand new needle. Sewists are known to be very frugal about changing needles but it is usually the easiest and least expensive fix for a lot of problems.
Remove all the thread from your machine, clean the bobbin area of any lint, threads, etc. Be sure that you RAISE the presser foot BEFORE you thread the upper thread. This releases the tension disks so the thread will seat properly. Now, re-thread from the beginning verifying you are following the correct threading sequence (consult your manual).

The standard factory tension setting is the midpoint, ie of the range is 1-10, set the tension at 5 and then adjust from there.

Why is my thread breaking

Why Does My Top Thread Keep Breaking Sewing Machine

Why Does My Thread Keep Breaking While Sew

Sewing Machine Problem 1 Thread Breakage

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Check the machine's paperwork. It could still be under warranty.

Hopefully, your sister oiled per the manual instructions. Oiling a computerized machine is not advisable unless the instructions say to do so.

Ask your sister to try something:
Remove the top thread from the machine.
Install a brand new needle (verify it is facing the correct direction).
ALWAYS RAISE the presser foot and rethread the top thread--confirm it follows the correct thread path.
Set the top tension to the midway point.
Re-test the machine.

Go to the following web site and scroll down the page and read the reviews there:

Amazon com Singer 3221 Simple Sewing Machine with Automatic Needle...

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

Check first that you are using premium thread (not the cheaper type that you'd use in an overlocker/serger). Breaking thread could be because of one of the following reasons -
the upper tension is too tight, the machine isn't threaded correctly, the thread doesn't suit the fabric (I had the problem when sewing an item the other day and changed from cotton thread to polyester and it stopped breaking). In your instruction manual check at the back for a troubleshooting section where it should be listed with some solutions.

You need to remove the bobbin from the "race" by following the instructions in the manual. Give it a good clean and remove any bits of fluff and thread. Remove the upper thread also andmake sure that the tension wheel is clear of any broken threads and is on the correct setting. It may have been threaded wrong. The hand wheel not turning sounds like the bobbin area is jammed also.

i need help too i bought this machine for my 9 year old daughter i thought she was just breaking it bieng so young and inexperienced but my husband and myself have tried also and the same problem accured i tried to follow the instructions but they are so very hard to follow can someone please help me? I keep threading the machine the needle and the threading the bobbin but i get half a stitch and it breaks again. Does
anyone know what im doing wrong?

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

I have the same machine with the same issues. I am so frustrated! Here is how I am going to solve my problem in 4 simple steps:
Step 1. Open garbage can.
Step 2. Throw piece of **** supposed sewing machine into can.
Step 3. Cover garbage can, cursing loudly.
Step 4. Purchase a brand name sewing machine with a real warranty!