Thread balls up underneath - Necchi 4575 Mechanical Sewing Machine

increase needle thread tension up

Have you changed the needle ? Is the fabric a knit ? If the needle has been used for awhile, it may be dull. Many modern fibres are quite hard on needles, which need to be replaced fairly often.



Many knit fabrics require a ball point or Q needle.. [ Kenmore\'s brand of ball point knit needle]. Many knits are notorious for causing skipped stitches and a special needle for knits can really help with this.



If thread is bunching up, is this underneath or on top of the fabric ?

If it is underneath, the top tension may need to be adjusted. Mal adjusted top tension can cause a lot of problems, and the mechanism that controls it can become worn and may need service or replacement.

Thread balling up in the bobbin case usually indicates that the TOP thread is mis-threaded (usually at the take up lever). Check with your manual for proper threading path.

It's most likely not the machine. It's the other things, ie needle, thread, etc. combination. For sewing knit, be sure to use a ball point needle. The needle eye size is important to so the thread is neither too small nor too large for the thread weight.

FWIW, it sounds like bird nesting. --the thread is not seated completely in the tension disk. Remove the top thread from the machine and ALWAYS RAISE the presser foot when rethreading!

Also, check that the tension is appropriate for the project. The two threads should meet in the middle of the fabric. If there is top thread showing on the underside of the fabric, the top tension is too loose. Tighten it until it until the top thread pulls the bobbin thread up into the fabric.

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it sounds like the top thread is not being pulled back up properly
make sure the machine is threaded properly with a new needle. (sorry for stating the obvious)
otherwise you can try
higher thread tension on top thread
larger size needle.
thinner gauge thread
different material

one or more of these should cure the problem

I find that re-threading both top and bottom threads fixes the problem. Sometimes the thread has not gone through the tension springs properly. try a new needle too.

When the thread is bunched up underneath, the problem is often in the top tension. The top thread is pulled through to the bottom but because there is no tension, it isn't pulled back up correctly, creating large loops underneath.

Try making sure that the thread is lying correctly between the tension disks (you can just see them inside the machine on the downward thread path). Lifting the presser foot lever (behind the machine) opens up the disks and lets the thread slide between them more easily. They will close again when you put the presser foot down to sew. Make sure you always thread the machine with the presser foot lever up and tension disks open to avoid this problem in future.

If the thread is running correctly between the tension disks, just check that you that there's no fluff caught in there, holding them open. Give it a blow, or run a folded pice of fabric through there.

Totally rethread your machine and install a new needle. Your thread could be tangled. Usually the top threading is the culprit, not the bobbin. Check your manual, it is surprising, sometimes you think that you have it threaded right and it isn't.

try taking out the bobbin and turning it around if that dosen't fix it then you need a new bobbin case

I've found that my machine doesn't like Coats & Clark thread; I have to feed it Guterman