Selecting a serger stitch

When you do opt for a serged seam or edge-finish, choose the stitch that matches the needs of your garment. Keep in mind that a serger stitch with fewer threads can have a lot of strength and stretch. Stitches with more threads tend to be bulkier rather than stronger, though there are exceptions, like the superstretch, three-thread wrapped stitch. And stitches incorporating the chainstitch make a stable, nonstretchy seam.

As a rule, use a narrow stitch with fewer threads for lightweight fabrics, wrapped stitches for maximum stretch on knit seams, overlock stitches for standard seams on knits and wovens, and wider overlock stitches with the most threads for ravelly or bulky fabrics. Flatlock stitches are wonderful for sportswear that needs to be comfy on the inside, and rolled-hem stitches finish delicate sheers beautifully. Thread tensions may need adjustment depending on the particular fabric and for flatlock and wrapped stitches.

To reduce the bulkiness of serged seams that use a lot of thread, use a long stitch length. Be sure to experiment with stitch length on a sample first. If the stitches are too far apart, the resulting seam may not be strong enough, especially on loosely woven fabrics. 

On many machines, for two- and three-thread stitches, you can choose between using the left needle for a wide stitch, the right for a narrow stitch, or using the machine's rolled-hem function to produce a very narrow stitch (see the photo at left). And don't forget embellishment: Take advantage of the fact that a serger's loopers don't pierce the fabric, meaning you can use heavier, decorative thread in one or both loopers to turn a seam or edge-finish into a design element.

The names of the stitches may be confusing at first, and may vary slightly from manual to manual, but all relate to how the stitches are formed. Two-thread stitches are generally called overedge, or overcast, because the threads don't interlace at the needle. Three-, four-, and five- thread stitches are referred to as overlocked because the needle thread interlaces with the loopers to form a knot at the needle line. And when the looper thread completely encircles the edge of the fabric on some two- and three-thread stitches, the stitches are called wrapped.

Once you become familiar with the wide variety of stitches offered on sergers, you'll develop a sense of when to use a stitch. Then use them often so your garments will look better and last longer. Here are just a few of your options.