feed dog

A feed dog is a metal component on a sewing machine with a series of small teeth or ridges that grip and advance fabric during sewing. It sits directly beneath the presser foot and moves in a four-part cycle: forward, down into the fabric, back, and up, releasing the material so the next stitch can be formed. This repeating motion pulls the fabric through at a controlled pace, keeping seams straight and stitches evenly spaced.

Feed dogs vary in design depending on the machine type. Industrial lockstitch machines use larger, more aggressive dogs with deeper grooves to handle heavy materials like denim and canvas. Domestic machines typically have shallower, finer teeth. The height of the dog relative to the presser foot is critical; if misaligned, the fabric will either bunch or slip. Some machines have feed dogs positioned to handle multiple layers; garment factories need dogs that grip through eight or more plies without slipping.

When feed dogs fail

Worn or flattened teeth stop gripping effectively, causing uneven stitch length or fabric creep. Thread lint and lint particles jam the mechanism, requiring regular cleaning with a small brush and tweezers. A bent feed dog, often from impact or dropped presser foot, cannot retract properly and will crease or snag lightweight fabrics. Most machines allow the feed dog to be disengaged entirely by a lever or button; this is essential for free-motion quilting and darning, where the operator controls fabric movement manually.

The term "feed dog" is British industrial terminology, derived from the rapid, dog-like motion of the mechanism. On industrial machines, feed dog height is adjustable and must match the presser foot pressure; improper matching is the most common cause of feeding problems on the shop floor. Replacement feed dogs are wear items, available in different profiles for specific fabrics: fine grooves for silk and cotton, coarse grooves for upholstery and leather.