Where is the tension on sewing machine?

There are two tension adjustments on the home sewing machine. One is the top tension and the other is the bobbin tension. Both tension settings regulate the tension on the sewing thread.

The top tension regulates the amount of tension on the thread that moves between the thread spool and the needle which produces the top stitches in your seam. The tighter the tension, the more taut the thread. The looser the tension, the more slack the thread. If tension is too high, the thread is strained, the stitches are tighter and the thread may break. If tension is too low, the thread is slack, and the stitches are loopy and loose. At ideal tension, the thread moves smoothly through the thread path and produces top stitches that are nice and even.

The bobbin tension regulates the thread spinning in the bobbin and being pulled up into the bottom stitches. At ideal tension, the bottom stitches are nice and even, and cannot be seen from the top of your stitching.

Refer to your sewing machine manual for the ideal tension setting on your particular sewing machine.