I am trying to figure out how to adjust the tension on my Simple little Singer Sewing Machine. I've been trying to sew 1/2 square blocks. I set the stitch length to 2.5 and the tension setting is a 3 (which is how the machine came). Am using 100% cotton fabric, thread on top and bottom, and have a new quilting needle.

Here's the problem. - The machine has decided to either sew miniscule stitches, or to sew long stitches that don't seem to be locked. (Looks like a long string of thread with an occasional stitch across them) The sewing "bunches up" and I have to hand straighten out every line. I know there is some screw on the bobbin and something extra on top of the machine to adjust tension --- but I am scared to try, because I don't know anything about settings.

Can anyone help with a generic tutorial?

Try cleaning the machine first before adjusting any tension settings. Look for a miniscule piece of thread in the bobbin case. A friends machine was doing very similar things and no matter what the tension was set at it wouldn't fix the problem. Found that tiny piece of thread stuck and magically the machine worked just fine again!

There are a lot of genius' on here that can probably help.
Try re-threading your needle or changing the needle. There are lots of tutorials on Youtube.

Make sure the needle is in the right way--according to the manual. And I would set my stitch length at 2 ---less likely to put apart at the ends--(once you get the other problem solved).

Is that the name of the machine (Simple little Singer Sewing Machine?). Different models have different ways to set the stitch length. On my 15-91 you have to unscrew the button, set your stitch length, move the button there and tighten.

How's it coming? Any luck? G

Have you put your bobbin in backwards? Sometimes when I'm not paying attention I thread it wrong and it does what you are saying.