What happens if bobbin tension is too loose?
A: Looping on the underside, or back of the fabric, means the top tension is too loose compared to the bobbin tension, so the bobbin thread is pulling too much top thread underneath. By tightening the top tension, the loops will stop, but the added tension may cause breakage, especially with sensitive threads.
How do you tighten thread tension?
Changing Bobbin Tension
You should see a small screw on the flat/closed side of the bobbin case. Turning the screw a tiny bit counterclockwise will loosen the bobbin tension; turning it clockwise will tighten the tension.
How do I reduce bobbin tension?
To decrease the bobbin tension – loosen the screw by turning it to the left (counterclockwise). Move the screw only a quarter turn or even less at a time. Test your adjustments on a piece of fabric you are going to use for the project and remember – a little turn of the screw can have a big impact on the tension.
Why is my bottom stitch not straight?
If your thread is pulled tight on the underside and not forming an even stitch then (counter-intuitively) it’s usually the top thread tension that’s wrong. Sometimes very lightweight fabrics such as sheers can get dragged down into the machine so it’s a good idea to use a straight stitch plate.