Bobbin thread is showing through on top of fabric

So, it sounds like the bobbin thread is coming to the top of the fabric and the top thread simply lays on top of the fabric. Just a hint: If the thread problem appears on top of the fabric, it is usually a bobbin thread problem. If the thread problem appears under the fabric, it is a top thread problem.

Is the top thread tight, ie pulling the bobbin thread up? Try loosening the top tension.

If that doesn't resolve the problem, then you probably need to tighten the bobbin tension.

Understanding Thread Tension on Your Sewing Machine

Not quite understanding your question. The standard top thread tension setting is the midway point between high & low numbers. If the bobbin thread is coming to the top of the fabric, loosen the top tension. If the top thread is showing under the fabric, tighten the top tension so it will pull more bobbin thread up into the fabric.

Check your stitch sample. Is it the bobbin thread that is making a thread mess, or is it the top thread throwing thread globs under the fabric? Usually, if there is a thread problem under the fabric, it is a top thread issue.

Try this:
Remove the top thread completely from the machine.
Install a brand new needle
ALWAYS RAISE the presser foot and rethread from the beginning. Verify the thread path is correct.
Retest your machine and tweak the tension, as needed. If top thread is showing under the fabric, tighten the top tension. If the bobbin thread is showing on the top of the fabric, loosen the top tension. Tension is correct when the two threads meet in the middle of the fabric.

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Since we don't have a clear picture of what is happening, we can't offer much in the way of advice. Here is something to try:

Remove the top thread from the machine.
Be sure to install a brand new needle.
ALWAYS RAISE the presser foot and rethread the top thread from the beginning. Verify the thread path is correct.
Remove the bobbin and rethread it into the bobbin case and install it in the machine. Make sure the bobbin is turning the correct direction in the bobbin case.
Set the top tension to the midway point (the factory standard tension).
Retest the machine.
HINT: Thread issues appearing under the fabric are usually a top thread problem. Thread issues appearing on top of the fabric are usually bobbin related.
If top thread is showing under the fabric, tighten the top tension.
If bobbin thread is showing on top of the fabric, loosen the top tension.
If problems continue, the bobbin tension may also need to be adjusted. HOWEVER, that is a last resort and a very tricky change to make. Be sure to mark where the tension screw is set BEFORE making any changes to the bobbin tension screw (so you can reverse your changes if it doesn't work).

You can also try changing the type & size of needle and the brand/weight of thread. AVOID old or bargain bin threads. Your needle choice, thread, and fabric should be compatible. Using the wrong needle can cause huge problems with stitching success.

Understanding Thread Tension Threads

uually your tension should be set between 4and 5 this is a good tension for most fabric

Check your stitch sample. Is it actually the top thread showing under the fabric, or is it really the bobbin thread. Generally, thread problems under the fabric are an upper thread problem. Thread issues above the fabric is a bobbin issue.

Try a brand new needle.
Remove the top thread from the machine.
ALWAYS RAISE the presser foot and rethread.
Remove the bobbin, check that it is wound smoothly, and install and thread the bobbin case making sure the bobbin spins the correct direction.
From that point, there may need to be some tension adjustments required.

Understanding Thread Tension Threads

If the problem continues, you may need to have it serviced. Perhaps there is a burr or snag somewhere that is interfering with the thread in the thread path.

Yes Adjust to more tight see what it'll do.
Bottom bobby is too tight or upper thread control is too lose.

Good luck

Mai

Remove all the thread from the machine.

Install a brand new needle.

ALWAYS RAISE the presser foot during the threading process and rethread the machine from the beginning. (Check that the upper and bobbin threads are threaded correctly in your machine.)

Set the tension dial to the midway point. This is a factory standard setting but each machine may vary.

Test your machine. The ideal tension is when the upper and bobbin threads meet in the middle of the fabric. If the upper thread is showing on the bobbin side of the fabric, the upper tension is too loose. However, if the bobbin thread is showing on the top of the fabric, the upper tension is too tight.

Tension is not static--whenever you change projects, ie fabric, thread, needle, you may need to test the tension on some scrap project fabric first. Get the tension adjusted before stitching the project.

Make sure you clean and lubricate your machine regularly to keep it operating--consult your owner's manual and use only good quality sewing machine oil (NO 3-in-1, cooking oil, WD-40, or old brown stinky sewing machine oil).

If you are still having issues, take it for service.

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The bobbin thread is being pulled too hard by the top thread. The idea is to get an even pull similar to a tug of war. When it is even the thread will form a knot in the middle of the fabric.
To fix this so the top thread isn't pulling too hard lower the tension of the top thread. This should fix it.

loosen your top tension... run a test seam. Loosen some more... test.