Definition
Feed dogs are the small toothed metal bars under the presser foot that rise through the needle plate and move the fabric forward between stitches.
Feed dogs move in a loop: up through the slots in the needle plate, backward to pull the fabric along, down, and forward again, once per stitch. The distance they travel sets the stitch length, and reverse sewing runs the loop the other way.
Good habits:
- Let them do the work. Pushing or pulling the fabric fights the feed, causes uneven stitches and can bend the needle.
- Mind the bottom layer. The feed dogs grip the lower layer while the presser foot slows the upper one, so the bottom layer is fed slightly faster. Sewists use this on purpose by putting the longer piece underneath when easing, as with a sleeve cap. When you do not want it, a walking foot adds feed teeth on top.
- Start on fabric. Starting right at the edge of thin fabric lets the feed dogs pull it into the needle plate; start a few millimeters in, or sew onto a scrap first.
- Keep them clean. Lint packs in under the needle plate and weakens the grip. Remove the plate and brush the feed dogs every few projects.
Most machines let you lower the feed dogs, or cover them with a plate, for free-motion quilting, darning and sewing on buttons by machine. Learn more in sewing machine basics.