Thread tension bottom side has loops - Sewing Machines

Looping stitches can be caused by a few different factors. Make sure that your machine is threaded correctly. If the top thread or bobbin thread is improperly threaded it can cause looping stitches. ... Loose thread tension will create loose loops of thread that can cause the needle to catch and create more of a mess.
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Looping on wrong (bottom) side of fabric is almost always insufficient tension of top thread.

The fabric appears to be multiple layers high density so it will take a higher than typical tension setting.

You can easily verify it is top thread looping on bottom by using a different color top thread. Using a different color top thread will also aid in setting the proper tension as you'll be able to see bottom thread eventually come to top side as you increase tension. Then reduce tension until stitch returns to center of fabric layer.

Check that top thread tensioner is engaging.

After threading top thread, with presser foot up, rotate tension selector to 4. Then move presser foot down (this engages top thread tensioner). Make a slow steady pull of the top thread. Compare tension to when foot was up (no tension) to foot down (selected tension). If you move presser foot up and down while slowly pulling the top thread, you should feel the change from no tension to selected tension.

If you find there is no tension on the top thread, the top thread will loop and nest on bottom side of fabric. Rethread top thread per machine instruction. If still no top thread tension, either the tensioning mechanism has failed or it has not threaded properly.

Once you have verified the top thread tensioner is working, you need to check bobbin thread tension. Make a slow steady pull on the bottom thread. You should feel tension similar to the top thread with tension selector set to 4 and foot down. If the bottom thread tension feels loose, similar to top thread presser foot up, then likely the bottom thread has escaped the bobbin case tensioner. Reload bobbin and recheck bobbin tension.

it is called bird nesting and is the result of the needle thread tension being too low
recheck that the thread is between the tension plates and not behind them
or disregard the settings and set ti manually
as if you are going to thread the needle , pull the thread and there should be a reasonable amount of effort needed to pull the thread
If there is not resistance to the pull then the tensioner is not applying the necessary tension

Most likely there are jamming threads at bobbin room under the machine stepping pedal, try to dismantle it to get rid of these threads.

If the bottom thread is tight there should also be loops on top and this means that the upper tension is too tight.
Get out your manual (http://www.singerco.com/uploads/download/1198_8763-efs.pdf) and turn to page 24. Under "ADJUSTING TOP THREAD TENSION" it tells you that if you're having thread tension issues, change the tension control dial on the top of your machine from auto. It also shows you a diagram with your problem illustrated on the right side of the page. The bobbin tension is set at the factory, so all tension problems can be solved with top tension adjustment. Set it manually and if it loops on top, loosen the tension a little. Test again. Repeat until loops are gone.
Using different colours on top and bobbin and a contrasting fabric (e.g. black top, white bottom, light blue fabric) means you can easily see what's happening. A perfect stitch is when you see exactly the same stitch pattern on both sides of the fabric. On top, the bobbin thread colour appears between stitches as a tiny dot and on the bottom, you see the top thread dot between stitches.
If it's impossible to get the tension right, take it to a technician, because it's a sign that the hook timing needs attention.

loops on the bottom means top thread isn't getting tension. Re-thread top thread with presser foot UP. Then test your seam again. If you still have loops, tighten the UPPER tension.

Thread looping on the bottom means you have a problem with the top thread. In your case there is no tension on your top thread. Take all the thread out of the top and start threading over. Make sure you follow the correct path and make sure the thread goes through the tension discs. Then at the time of sewing, make sure your foot is down (this closes the tension discs and gives the thread the tension.) You may have worked on the tension setting while not realizing the thread was not in between theses discs, so also make sure the top tension disc setting is in the average before sewing.
Good luck.

(If you see loops on top, it means you have a problem with the bottom thread)

Rule of thumb.. Loops on the bottom, problem on the top. Loops on the top, problems on the bottom.

Set your upper tension at 4, and rethread the machine from the top. Just before you thread the needle, but the presser foot down. If the thread pulls right thru easily, then the thread is not thru the tension wheel right. Because, if you can't pull the thread thru with the presser foot down, you have it threaded right.