Other stitch formations

Zigzag are lockstitches with a side-to-side width as well as a stitch length. Basic stitch formation is dictated by a stitch pattern cam; maximum pattern width is established by the stitch width regulator. The cams that produce zigzag stitch patterns are single. As the cam rotates, a fingerlike follower, connected to the needle bar, rides along the cam and tracks its indentations. As the follower moves in and out, the needle bar is moved from side to side. A zigzag stitch has more give than a straight stitch, and therefore is less subject to breakage.

Stretch stitching are produced by coordinated motions of needle and feed. While the needle is moving, as for straight or zigzag stitches, the feed is automatically moving the fabric forward and backward. As with zigzag stitches, stretch stitching is cam controlled, but because of the dual action, stretch stitch patterns have double cams. As the double cam rotates, the follower, connected to a needle bar, rides along one track to move the needle bar from side to side. Another follower, connected to the feed, simultaneously rides the other cam track to move the feed for forward and reverse stitches as required by the design. ^[8]