Serged Seams

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Learn all about serged seams. The sound of the serger, flying across your fabric, brings out the eagerness in a sewer to surge forward and get an amazing amount of sewing done all in one electrifying moment. Sergers, also known as overlockers, sew with an all-in-one finish. They sew the seam, trim the seam allowance and neaten the seam with an overlocking stitch all in one motion. All you have to do is direct this champion machine across your fabric. The serger can either do an all-in-one process for you, or you may just want to stitch as normal, and serge afterward to neaten off the seam.

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Whatever you decide to do, to neaten your seam with a serger, it is a good idea to know something about the serger’s stitch capacity. Different sergers, according to the number of threads they support, produce a variety of stitching.

Read up on your model and have some lessons if they are available and know what you can expect from your machine. Sergers come in different sizes and models. They have different numbers of threads and may do a double line of stitching, or a single, depending on how many needles you thread. The more threads on the machine the stronger and wider the sewing will be. Even if the machine has up to five threads there is no need to use all the threads. It is possible to sew with the serger and use fewer threads. The serger will always trim and neaten, but with fewer threads from the loopers and the needles. The important thing is to ascertain the number of threads that best suit the fabric you plan to sew and to practice on a scrap first.

A serger is not an essential piece of equipment to sew and neaten beautiful seams. However, the advantage of the serger is its ability to finish everything all in one motion. It is a machine that makes your sewing look professional. Once you have practiced a few different seam techniques, you will have the confidence to use the machine all the time.

How to Sew Serged Seams

Here are the steps to take to complete straight forward serged seams.

Step 1 - Test

The first step is to practice your serger stitch on a scrap of fabric you plan to sew. The loopers and the stitches and the tension of the serger must be regulated to fit with the fabric. The serger is going to cut as well as stitch. For this reason the tension and seam width must be exactly as you would like it to be. A serger is a speedy little machine and getting used to how it sews is a very important step to take.

If this is your first time, read how to use a serger before you start.

Step 2 - Sew the Seam

Prepare your seam. Sewing with a serger, and knowing your machine is going to cut and trim, means you must avoid pinning where possible. Your machine blade will get damaged if it rides over a pin. There are two options. You can baste the seam or you can machine stitch with a row of stitching using your normal machine. If you are making a pattern you know well or an easy-to-make style you may feel confident to sew freestyle without pinning or basting.

Step 3 - Serging

Get ready to serge along the seam and watch how your machine can cut and sew and neaten all in one swoop. You will feel confident in this step if you have prepared and practiced.

Step 4 - Finishing

Make sure you left a ‘tail chain’ at the beginning and the end of the seam. There is no backstitch on the serger.

To capture the neatened part of the serger’s stitches it is important to leave a chain of stitches. This chain of stitches will be used to thread the chain back into the seam allowance when the seam is completed. The chain can be threaded back on itself using a large eye needle to thread the chain tail and push it back through the stitching. Threading the chain back on itself is essential to the finishing-off process and ensuring there is no seam unraveling.

These four steps form the basics of seam neatening and sewing serged seams. There are some other techniques and variations to consider depending on the garment, the fabric, and the amount of strength required from the seam.

Serged Seams with Corners and Curves

See my article on how to use a serger for extra information and tips on sewing corners and curves for your serged seams.

Other Serged Seams

Here are some other ways to use the serger to neaten and sew serged seams.

Closed Serged Seams

Sew your seam with your regular sewing machine along the seam allowance. Finish the edges together with your serger and press the seam to one side.

This is the basic seam using the serger with the straight sewing threads forming the seam and the looper threads making the overclocking edge. It is your choice as to whether you need three or four or five threads for your all-in-one closed seam on the serger.

Open Serged Seams

There are two ways you can sew open serged seams by altering the order of the steps.

Sewing the Seam First

Stitch the seam with your regular sewing machine along the seam allowance. Finish each raw edge separately with the serger then press the seam open.

Serging First

You can also finish the edges first before you sew the seam. Neaten the raw edges and take into account how much of the seam allowance has been trimmed by the serger. When the edges have been serged and trimmed, sew your main seam with less allowance. You could also choose just to overlock the seam allowance and disconnect the blade of the serger and not have any of the seam allowance trimmed.

A Serged French Seam

Use the serger to start your French seam and get a really neat edge to tuck into the seam. This is a great way to take advantage of the serger’s ability to overlock and trim.

Set the serger on a narrow three thread setting and put your fabric wrong sides together.
Serge the first part of the French seam. You will serge according to the amount normally used in the first part of sewing a French seam.
Press the seam and turn the seam to allow the right sides to meet. The serged part of the seam will be enclosed.
Use your normal machine to stitch down and complete the French seam. The neatly overlocked edge will be enclosed in the French seam.
Read more about French seams.

Serged Seams - Number of Threads

The Two Thread or Flatlock Stitch - This interesting stitch joins two pieces of fabric together and the seam, including its neatening, is pulled open to lie flat. The finished seam has a ladder effect on one side with two rows of parallel stitches on one side of the seam and the looper stitches on the other side.
The Three Thread Serged Seams - The three-thread stitch neatens the seams of stretch fabrics. The three-thread serged seam is a narrower seam and not as strong as the serger stitched with four threads.
The Four Thread Serged Seams - The four-thread finishes off a strong seam with a neat finish. It has an extra stitch through the middle of the over-locking threads. This extra stitch is known as a safety or extra strength stitch.

Serged Seams for Denim and Heavy Duty Fabrics

The serger is a really good way to prevent fraying in denim or other heavy-duty fabrics. Try your serger out on your denim fabric sample using two pieces of denim together to check the fabric is not too thick for your serger.

If your model of serger is reluctant to serge two pieces of fabric together then neaten each side separately. Use the serger to neaten raw edges before starting to sew the seams. In this way, the seam is neatened and fraying prevented before the seam is sewn together.

Pass the fabric through the serger carefully. Do not be tempted to pull the denim through the serger as this may cause the fabric to stretch or pull out of shape. It may cause the serger to stitch incorrectly and lose tension causing the threads to tangle or snap.
After the neatening is complete sew the seams together with your normal machine and press the edges that have been overlocked open.

The serger is ideal for neatening seams of heavy-duty fabrics that fray easily. The neatened serger edges of heavy-duty fabrics, hidden inside a lining of a jacket for example, make sure the seam will not fray. The jacket lining encloses the over-locked edges of the seam, but the over-locked seam may not need a lining, because it is very neat and hard-wearing.

Serged Seams - In Conclusion

The serger makes all the difference to strengthening and completing seams. The ability of this machine to neaten and trim the edges of the serged seams gives the serger the cutting edge over other machines when it comes to neatening and strengthening seams. The hard-working multi-task machine known as a serger or overlocker gives the home sewn garment the professional look. It really is worth using this machine for neatening seams.