How do I adjust presser foot pressure?

Presser foot pressure is how hard the foot presses the fabric against the feed dogs, and it is a separate control from tension. Many people never touch it, and a fair number of feeding problems are simply pressure set wrong for the fabric.

Where to find it. On most machines, a dial or a screw on the top of the head above the presser bar, on the left. On some it is a numbered dial; on older machines it is a screw cap you turn down. A few modern machines set it automatically and have no control at all — check your manual before hunting.

Reduce the pressure for thick or lofty fabric, wadding, fleece, several layers, and anything that the foot is compressing so hard that it cannot feed. The classic symptom is a quilt sandwich where the lower layer advances and the top one does not.

Increase the pressure for fine, slippery and lightweight fabric that skids under the foot, and for anything the feed dogs are failing to grip.

Reduce it also for knits that stretch and go wavy under the foot. Excess pressure stretches jersey as it feeds, which is a common cause of rippled hems.

Test on a doubled scrap of the actual fabric and adjust in small steps. Change one thing at a time — chasing feeding problems with tension and pressure simultaneously tells you nothing.

Set it back afterwards. A machine left on a low pressure setting feeds ordinary fabric badly.