The bobbin is not preforming properly. It jumps around when I sew and then on the back of the fabric there is a ton of excess thread.

You do not have the tension on your machine set correctly. That is leaving the bobbin thread too loose, hence the loops you are seeing. What kind of machine do you have? I can tell you where the tension is located. Also, tell me what kind of fabric you are trying to sew. FIRST JUST SET IT BACK TO THE FACTORY DEFAULT. When you are moving the machine it is easy to accidentally hit the tension and change it. Here is a picture of what a tension knob looks like. Good luck.

Is it really the bobbin thread that is globbing? Check closely. Usually it is the upper thread accumulating under the fabric.

If it is in fact the bobbin thread, then the bobbin case is not threaded correctly, the bobbin case tension needs adjustment, or it is broken and needs replacement. There are web sites and YouTube videos that show how to adjust the bobbin case tension.

QUICK FIXES: Remove all the thread from the machine. Clean the area around the feed dogs and bobbin area. Oil as instructed in the owner's manual using ONLY fresh, good quality sewing machine oil (only 1-2 drops each spot). Install a brand new needle insuring it is installed correctly. Avoid using fuzzy, old, or bargain bin thread. Rethread: Be sure you raise the presser foot BEFORE threading the upper thread so it will seat properly in the tension disk--and check to make sure you are threading the machine correctly. Check that the upper tension is set properly (the factory standard is usually the halfway point between the high & low number on the selection). Test on a scrap of the fabric you wish to sew. Adjust the upper tension--either tighten to pull the upper thread toward the top of the fabric, or loosen to pull more upper thread down.

Here are some web sites that may help.

Sewing Machine Thread Bunching Up Here Why

sewing machine birdnesting

https://answers.yahoo.com/question/index?qid=20100303212248AAnRUQA

8 Tips to Fix Birdnesting in Embroidery

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

3 Common Sewing Machine Problems and How to Fix Them

...

Skipped stitches
1. The needle is not inserted correctly
Remove needle & reinsert needle( flat side towards the back of machine)
2. The needle is damaged
replace with new needle
3. The wrong size needle is being used
Choose a needle to suit the thread & fabric
4. The foot not attached correctly
Check & attach correctly

bird nesting problems

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



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

try changing the needle---flat side goes to the back side of the machine
also check the top tension
depending on the fabric your sewing on--the needle & thread have to work
with the fabric--example light fabric needs a different needle & thread than
a heavy fabric
check to see if the thread is coming off the thread take up lever when you
sew.

Your bobbin is not installed correctly.There should be an excess thread coming out of the bobbin. Second-the thread wheel is the other way around,it should be positioned to follow where the extra hair of thread is to be going.And once you insert it in you'll notice a snap and the bobbin is settled firmly and locked into the shaft.

I had similar problems when I first started sewing. Try adjusting the tension in your thread - less tension for lighter fabrics, more tension for heavier fabrics. This will stop the needle from pulling the threads in the fabric.

As for the thread getting bunched up in the bobbin - this is most likely because your bobbin is the wrong size for the machine, or that you did not thread the bobbin properly. Try re-threading, this time making sure you pull the thread into the bobbin container tightly. This should stop the bobbin from jumping around the container and spitting thread.

Although I am not a expert at sewing machines, I have worked a lot with an industrial sewing machine. You might check the tension of the thread that goes through the needle. If it is to tight it will pull it through the needle. There should be somewhere on your machine that you can adjust the tension.

It sounds as though the thread is jumping out of the tension assembly. The next time this happens, do not raise the presser foot before you do the following.Cut the thread above the needle and pull on it.If it is working properly there will be tension on it.If it is not working properly, the thread will pull through very easily.If the thread is coming out of the tension , either it isn't threaded correctly or you may need to wrap the thread around the bobbin winder guide to keep it from coming out.If you wrap it around the bobbin winder guide reduce the tension to around 2 , 3 or even less.
Hope this helps.
sewman7

I once heard from a great sewing instructor that if the problem is on the back of the fabric then it is a spool to needle problem.... if the problem is on the top of the fabric, then it is a bobbin problem. Check your machine for dust and stray threads. Check your bobbin casing for dust and stray threads.

Question: How does one find the tension discs??? I have a White 1740 with a top drop in bobbin and I went thru the same problems as night_wolf above, then, ultimately, the top thread will now not pick-up the bobbin thread through the fabric. It picks up the bobbin thread without fabric in play, but once fabric is added (for free motion quilting) it won't pick it up. This is after using the machine for the last 10 days to piece and quilt without a problem until this morning.

I'm at a loss.
Tks, Candace