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05.08 How to Use a Serger

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A serger, also known as an overlocker, is a sewing machine that trims the fabric edge, sews it together, and finishes the seam in one step. Sergers are often used for finishing seams on knit fabrics, as well as for sewing garments, home décor projects, and crafts.

Threading a Serger

Threading a serger can be a bit tricky at first, but it gets easier with practice. Most sergers have color-coded thread guides to help you thread the machine correctly.

To thread a serger, you will need to thread the upper looper, lower looper, and needles.

  • Upper looper: The upper looper thread is the most visible thread on the finished seam. It is important to use a good quality thread for the upper looper, as it will be the most stressed.
  • Lower looper: The lower looper thread is the thread that forms the chain stitch on the back of the seam. It is less visible than the upper looper thread.

Consult your serger’s manual for specific instructions on how to thread your machine.

Adjusting the Serger Settings

Once the serger is threaded, you will need to adjust the settings. The most important settings to adjust are the stitch length, differential feed, and thread tension.

  • Stitch length: The stitch length controls the length of the stitches. A shorter stitch length will produce a stronger seam, but it will also be less stretchy. A longer stitch length will produce a more stretchy seam, but it will also be less strong.
  • Differential feed: The differential feed controls how much the fabric is stretched or fed as it is sewn. A differential feed setting of 1:1 will produce a balanced seam. A differential feed setting greater than 1:1 will stretch the fabric as it is sewn, which is useful for sewing seams on stretchy fabrics. A differential feed setting less than 1:1 will gather the fabric as it is sewn, which is useful for sewing seams on delicate fabrics.
  • Thread tension: The thread tension controls how tightly the threads are sewn. If the thread tension is too tight, the fabric will pucker. If the thread tension is too loose, the stitches will be loose and the seam may not be strong enough.

Basic Serger Stitches

The most common serger stitch is the four-thread overlock stitch. This stitch is used to finish seams, hem fabrics, and sew garments. Sergers can also sew other types of stitches, such as a three-thread overlock stitch, a rolled hem stitch, and a flatlock stitch. Consult your serger’s manual for instructions on how to sew different types of stitches.

Using a Serger

Once your serger is threaded and you have selected the desired stitch, you are ready to start sewing.

  1. Place the fabric edges under the presser foot, generally with the right sides of the fabric together. Make sure that the fabric edges are aligned with the seam guide on the right side of the presser foot.
  2. Lower the presser foot and start sewing. The feed dogs will pull the fabric through the machine.
  3. Guide the fabric through the machine, keeping the edges aligned.
  4. To finish the seam, sew off the edge of the fabric and lift the presser foot.
  5. Pull the fabric away from the machine and trim the excess thread. The excess thread can be pulled back through the overlocked stitches to lock it in place.

Tips for Using a Serger

  • Use sharp needles and quality serger thread to help prevent puckering and broken thread.
  • Adjust the stitch length and differential feed to suit the fabric you are sewing.
  • Test the stitch on a scrap of fabric before sewing your project.
  • To finish a seam, sew off the edge of the fabric and lift the presser foot. Pull the fabric away from the machine and trim the excess thread.

Serger Video Tutorials