Makes one stitch then abrupt stop with threads bunching up from bottom

Make sure your presser foot is in the up position before you thread the machine. Dull, bent needles will cause stitching problems, can make the machine work harder, or can damage the machine or your fabric so change the needles often; some say after two medium size projects. Dull needles can make a plucking noise so listen to the noise your machine makes right after you put in a new needle. Make it a habit to listen to the needle noise as you sew also. Dull needles make a "plucking" noise. Check to make sure the top thread is engaged between the two tension disks and that there are no fuzzies in the tension disk or bobbin/ throat plate areas. Make sure the thread and needle are compatable. Refer to your sewing machine manual or find an online chart that references your thread to the proper needle type, size and the proper fabric types that work best. Use the same thread in both top and bobbin. Completely remove your thread and try another thread - top and bottom. 100% polyester thread is some times problematic. Some machines won't sew with certain threads. If nothing worked, you will probably need to adjust the top tension knob. There are some good youtube videos. Look for one with a higher number of views. Loops under the fabric means you need to tighten the top tension (turn knob to right) gradually until you get a proper stitch. Most experienced sewers do not like to adjust the bottom tension screw on the bobbin case if it can be avoided. Bad things can happen if the screw pops out :( !!! I have a friend who sewed all her own clothes in 4-H, high school, college, and many of her children's clothes. After about 40 years of sewing and properly maintaining her machine, I received a call from her because nothing she did worked to get her machine to sew a good stitch. She had no idea there is a bottom tension adjustment on the bobbin case. One last time...do not adjust the bobbin case tension unless you know what you are doing. The screw should never be unscrewed so that it pops out. It will often not go back in correctly. Some some sewing machine repairmen/women can rebuild the bobbin case if the screw is still good. A new authentic bobbin case from the manufacturer can be pricey. One of the most common problems are tension problems. Do not let children or inexperienced adults mess with your knobs. There are youtube vides that address just the bottom bobbin case tension adjustments. If you are working on an important project, write down the type of fabric and thread you are using, stitch length and width settings, and the number setting on your tension knob. Or you can take a picture of it on your phone. This is even more important for sergers. I also record this information for appliqu? stitches, top stitches and quilting stitches (etc.) and keep it with the pattern envelop so if I make the project again, I have a starting place and save time and frustration. I hope this helps you.

Please check whether it is the bobbin thread or the top thread that is messing up. If it's under the fabric, it is 99% the top thread and is called bird nesting or thread nesting.

Remove the top thread from the machine.
ALWAYS RAISE the presser foot and rethread from the beginning.
Verify the thread path is correct.
Also check that the bobbin is loaded and turning the correct direction in the bobbin case.
Now, retest the machine.

You may need to tweak the tension to get it where it looks best.

...

Try these suggestions
1. Change needle
2. Rethread the machine--top --make sure to use every thread guide
3. Take the bobbin out --make sure it is inserted correctly into the bobbin
Case, & make sure the bobbin is turned the correct way
4. make sure the thread has not come off the thread take up lever
5. Clean under the needle plate & in the bobbin area for lint or threads

try changing the needle
also try changing the top tension
clean under the needle plate & in the bobbin area for lint or loose threads

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

Yes, it does. There are a couple of reasons the bobbin thread could be bunching up on the underside of the fabric. It could simply be that the machine needs cleaning. Take the bobbin assembly out, brush all the old lint out as best you can, reoil the machine once it's all clean, and make sure there aren't any little bits of thread caught in the bobbin assembly. Rethread the machine (carefully) and change the needle. This solves the problem usually--especially if the machine was sewing along fine and the problem develops suddenly. '
The other thing to check is your tension. It could be that the top tension is too loose. But different color thread in the top and in the bobbin, stitch a few inches (be sure to held the top and bobbin thread ends behind your needle as you start to stitch) and check. WIth the pressure foot down, adjust the tension, and stitch again. Keep stitching, checking, and adjusting until you see little if any bobbin thread on the top or top thread on the bobbin.
Another thing to reminder: use the appropriate thread and needle for the fabric you're sewing.
Let me know if this works, ok?

Robbie

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.

the problem is always on the other side of the fabric - if thread bunches up underneath, the top tension or threading is wrong

Stop sewing! You need to adjust your tension. Your book will explain exactly how to do this. If you can't find your book, try setting the tensions to the same number. If your tension adjustments have a mark at a certain number, use that setting for most materials. If not, try setting it to about 3.

To test your settings, thread your bobbin with a different color, then do a test stitch. Check the top and bottom stitches for a spot of the other color thread showing through. If the bobbin thread shows in the top, raise the bobbin tension setting a bit and try it again.

Hope this FixesYa!

Hi,
Remove your needle plate, and take out the black bobincase. Check the edges on the black bobbincase for scratches or damages. The upper tread should glide smootly around the upper edge of this bobbincase.

If you find any scratches, you may use a very fine sandpaper/grindingpaper (not shure what you call this in english) to remove the scratches.