When attempting to sew the bottom of fabric "thread starts bunching up after about 3 stitches....Help....what is wrong

Your tension must be wrong. If the top tension is too weak the thread on the bottom is not being pulled through the fabric to form a proper stitch. Try different tensions on scraps of fabric.

Check your stitch sample. Dollars to donuts it's the top thread bird nesting (also called thread nesting) under the fabric. Issues appearing under the fabric is usually top thread related. Problems appearing on the top of the fabric is usually bobbin thread related.

Remove the top thread from your machine.
Be sure to start with a brand new needle.
ALWAYS RAISE the presser foot and rethread the top.

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Check your stitch sample. The loose stitches under the fabric--are they actually top thread???? Usually,stitch problems under the fabric is a result of a top thread problem. In this case, it could be bird nesting.

Remove the top thread from the machine.
Install a brand new needle.
ALWAYS RAISE the presser foot.
Rethread from the beginning.

Sewing Machine Thread Bunching Up Here Why

Birds nest under the fabric big loops of thread top side looks good...

make sure that the thread tensions are correct for the thickness of material
remember that only the bottom foot walks and draws the material through so it may need a help and be pulled as it sews.
I find that women in sewing shops just love to talk about problems and how they can help so find a shop and discuss any problems with them

I had/have the same problem...the gal at Joann's told me that it is USUALLY related to the needle being wrong for the fabric, an old needle, pulling as you sew, etc. Tweak everything possible, use a scrap fabric, keep resewing til machine behaves and then go to your real fabric. I always sew now with a scrap I test before doing something on the real piece. Also I was having bunching with my UNDERSIDE and assumed it was the bobbin thread. She told me the underside problems are from the top thread, not the bobbin thread..so she showed me how I was slightly threading wrong. I have a Singer Curvy and love it, but it is finicky when default settings are changed with stitch, width, length not matching the recommended settings. Good luck!

Make sure you hold thread in back of the lowered presser foot when you begin stitching, and that the needle is piercing the fabric so that the fabric isn't slipping down into the feed dogs (under needle plate area).Hope this helps you out,alexlefebvre.Jimmy

It very well could have a burr in on your bobbin case, If, it was me, I would take it to Sears sewing machine department and ask them what they think it could be. They sometimes have new bobbin cases right there for you to buy, depending how big your Sears is. It won't cost you anything, at least to find out from the saleman.

re-thread the top, when the top looks good but the bottom is bad it is the top thread

Make sure that there is tension on the thread when you have passed it through the tension unit, by making sure the presser foot is down, and then gently pulling the thread to feel tension. If there is no tension, as seems to be the case, check the tension discs inside the unit to make sure that there is no debris stopping them from closing.

Needle jams....Thread is caught in the hook...solution...Remove the upper thread and bobbin case,turn the handwheel backwards and forwards by hand and remove the thread remands.

Needles breaks
1. Needles is damaged..Insert new needle
2. The needle is not correctly inserted....insert flat side towards the back
3. Wrong needle size for the fabric...Choose a needle to suit the thread and fabric.