It is not sewing, it seems to be out of time. the bottom thread is very loose when I try to sew. what do I need to do to fix it.

With threading tension issues, first you start by checking the bobbin tension and once that is set correctly, everything is done using the top tension dial. This is explains in text article

What is Perfect Sewing Machine Tension? Perfect sewing machine tension occurs when the top and bottom threads are perfectly balanced. That means you shouldn't see any little loops on either the top or bottom of your fabric and the stitching should look even on both sides.

Sewing Machine Tension - Top 10 TIPS - Treasurie blog

The two top videos are excellent at explaining how to set bobbin tension, and how to diagnose where the issue is, top or bottom?

https://www.google.com/search?q=sewing+machine+tension

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If the upper thread is looping on the bottom of the fabric as you sew, the upper tension is too loose. It could be threaded incorrectly, the upper thread may not be seated in the tension disk properly (be sure to RAISE the presser foot BEFORE threading the upper thread), or the upper thread tension is set too loose.

If you have checked everything and it is still looping underneath, the bobbin tension may be too loose or the bobbincase needs replacement.

Sewing Machine Thread Bunching Up Here Why

Oh You Crafty Gal Sewing Lesson 10 How to Fix Tension on Your Sewing...

Understanding Thread Tension Threads

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Hello, If the thread is loose on the bottom then it is the tension on the top. If the thread is loose on top then it is underneath.

the bobbin tension is set by that small spring plate that you pull the thread under after you put the bobbin back in the carrier / holder
a very small turn of that screw makes a big difference ob the tension unlike the needle thread tension
mostly the problem ( you never bothered to mention the symptom ) is bird nesting under the fabric which is the needle thread tension not tight enough

try a new needle--one that is for the fabric being sewed
then try to adjust the top thread tension again, if the stitches remain loose and the tension won't adjust then the tension knob needs to be checked to see if there is something wrong with it.
also check to make sure the bobbin is inserted correctly into the bobbin case, if the bobbin is not turned the right way in the bobbin case the sewing machine will not stitch correctly.

If you belt broke it might be a gear needs lubrication..

It could be that you threaded the machine with presser foot down.

When the foot is down, then tension control is closed and the thread cannot seat for proper control to the needle.

What appears to be a bobbin problem is actually the top thread not having the tension needed (thead is not where it should be within the tension control) to form a stitch.

No, I have not had a consistent problem with this.

What looks like a bobbin issue could be a threading issue.

If a sewing machine is threaded with the presser foot down, the tension control does not capture the thread as it should. The top thread then cannot form a proper stitch with the bobbin thread.

If I forget to have the presser foot up when I thread, then I get loose stitching on top and loopy stitches on the bottom.

tighten top thread tension.

Hello, sewing is a part of my income and I've encountered this problem before and managed to fix it on my own, by trying out these different things. I re-threaded the machine and checked to make sure that the tension is not too loose. Check the bobin and the sack the bobin fits into, sometimes it comes loose too, click it back into place and re-do the bobin. adjust the tightness of the stiitches, I usually put it on 2 .5 - 3. Hope this helps. Good luck to all. [email protected]