Likely, you have already heard about serger machines, also referred to as overlockers. Perhaps you are asking this question: “What are these things?” and, "Do I need one?" 

Let’s unpack it from an easily understandable perspective with no use of complicated terms.

If you want to sew faster, avoid threads from unravelling, or work on delicate fabrics like stretch knits or thick synthetics – a serger could be of great assistance to you. Besides, it offers a professional look to your projects that are impossible when sewing with a normal sewing machine.

To start with let’s first understand

What is a Serger?

A serger or overlocker is different from an ordinary sewing machine, it sews seams and trims fabrics simultaneously, as it has a blade which cuts the fabric edge as the seam is being sewn, thus providing a smooth, even edge to your garments giving them a neat finish, a serger can make your life much easier and seams stronger as it uses multiple threads from 2 to 8, depending on the machine that you are using. Plus, it adds a professional touch to your projects that you just can’t get with a regular sewing machine.

Do You Need a Serger?

Frankly speaking, it all depends on what you want to do. If most of your work is with stretch fabric such as t-shirts or leggings, a serger will be a game changer. It’ll help you get strong and stretchy bottom seams that are not easily torn. But if you are not yet doing complicated sewing projects and you’re a beginner at sewing, you don’t necessarily have to buy one immediately. It’s like levelling up—use your regular sewing machine until you're ready for serging.

Key Things to Look for in a Serger

1. Threads: Sergers can use anywhere from 2 to 8 threads. The more threads, the more options you have for stitches. Most people go for a 4-thread serger—it’s the go-to serger for most sewing projects.

2. Stitches: Sergers aren’t just for finishing edges. They can do much more like rolled hems (think delicate fabric edges) or flatlock stitches (perfect for activewear). Some models even do cover stitches, which is the kind of stitching you see on t-shirt hems.

3. Easy to Use: At first, sergers can seem like they have a lot going on with all those threads. But newer models are pretty user-friendly. Some even have auto-threading, which saves you from any stress of arranging threads.

4. Extras: Some sergers come with attachments like presser feet that let you gather fabric or sew on elastic as you go.

How to Pick the Right Serger

Fabric Matters: If you’re sewing mostly stretchy fabrics (like t-shirts or activewear), a 4-thread serger is awesome. But if you’re working with heavier stuff like denim, a 5-thread might be better because it can sew and finish seams in one step.

Budget: Sergers can range from around $300 for a basic model to over $1,000 for the fancy ones. Make sure you pick one that fits your budget and your sewing goals.

Brand & Support: Some brands offer better support, like online tutorials or in-store classes. It’s worth checking what’s available in case you need help figuring things out later

1. Merrow/3 Thread Overlock

The 3-thread overlock is one of the foundational overlock stitches. Sometimes referred to as a "Merrow machine," this is the original overlock setup. A key feature of the 3-thread machine is that it only uses one needle and has three tension dials—one for the needle stitch, one for the upper looper, and one for the lower looper.

In terms of application, the 3-thread overlock is ideal for narrow edge finishes and creating a clean, dense seam on lightweight fabrics. The stitch is tight, with one needle thread acting as the base stitch and two looper threads wrapping around the fabric’s edge to prevent fraying.

If you're after a narrow, dense finish for a more delicate look, the 3-thread is your go-to.

2. 4 Thread Overlock

This is one of the most popular overlock setups. The 4-thread machine steps things up by adding two needles. This gives you a combination of a 3-thread overlock and an extra line of stitching for added security—known as the safety stitch. It’s great for medium to heavier fabrics where durability is important.

The beauty of the 4-thread machine lies in its versatility. You can remove one of the needles to convert it into a 3-thread machine for a narrower seam, or keep both needles to maintain that strong, reinforced seam. This setup is perfect for stretchy fabrics, as the safety stitch helps prevent the seam from popping.

3. 5 Thread Overlock

The 5-thread machine adds yet another layer of stitching: a chain stitch alongside the overlock. This gives even more strength and stability to the seam, making it perfect for heavy-duty projects, like jeans or upholstery.

A 5-thread machine still has two needles like the 4-thread, but it uses a combination of overlock stitching on the seam edge and a separate chain stitch farther away from the fabric’s edge for reinforcement. Just like with the 4-thread, you can use this machine as a 3-thread or go full five-thread when you need that added strength.

4. 6 Thread Overlock

The 6-thread machine is a powerhouse, combining the features of all the previous machines into one. It uses three needles and a combination of overlock stitches and chain stitches, giving you the ultimate versatility. You can create any configuration from a 3-thread up to a 6-thread stitch, depending on your needs.

However, this machine requires careful calibration to get the tensions and stitches just right. It’s more complex to use, but if you’re working on a wide variety of fabrics and projects, the 6-thread machine can be a great investment.

When to Choose Each Machine?

• 3 Thread (Merrow): Best for lightweight fabrics, narrow edge finishes, and when you need a dense, clean stitch.
• 4 Thread: Perfect for medium fabrics and garments like t-shirts, especially with stretch fabrics due to the added safety stitch.
• 5 Thread: Ideal for heavy fabrics and seams that require extra durability, such as denim or home upholstery.
• 6 Thread: A versatile option for those working with different types of materials and needing various stitch combinations. However, it may be overkill if you mostly work with basic fabrics

Why You’ll Love Using a Serger

1. Makes Seams and Finishes the Edges

One of the coolest things a serger does is create strong, neat seams and trim the extra fabric at the same time. It’s like sewing and cutting in one step! This makes sure your fabric doesn’t fray or fall apart at the edges, so it looks clean and professional.

Example: Imagine you’re sewing a pair of pants, and the fabric keeps fraying (like when little threads come loose at the edges). A serger cuts those threads and finishes the edges in one go, so the fabric stays smooth.

2. Works on All Kinds of Fabrics

A serger can handle everything from super thin and delicate fabrics to thick ones. This means you can use it for almost any project!

Thin Fabrics: If you’re working with something light and flowy, like chiffon or silk, a serger can sew tiny, delicate hems that almost disappear.

Stretchy Fabrics: If you’re making something like leggings or a T-shirt, which need to stretch, a serger is perfect as it creates seams that stretch without breaking, so your clothes move with you.

Thick Fabrics: It can also sew through thick materials like denim or fleece with ease—so you could even make your own jeans or cosy blankets!

3. Creates Stretchy Seams for Activewear

If you love making workout clothes or swimsuits, a serger is your best friend. It makes stretchy seams that won’t pop when you move around, so your leggings, swimsuits, or sports tops stay durable and comfortable.

4. Does Fancy Hemming (Rolled Hems)

A serger can make a super narrow, rolled hem that looks neat and is almost invisible. This is great for delicate fabrics like satin or chiffon, and it’s often used for formal clothes like dresses or fancy blouses.

Example: Picture hemming a flowy party dress with fabric so light that you want the hem to blend right in. The serger can make a tiny rolled hem that keeps the edge from fraying but is hardly noticeable.

5. Attaches Elastic with Ease

Need to sew elastic onto something like a waistband? A serger can quickly attach elastic to the fabric while keeping everything neat and stretchy. After you serge the elastic on, you can use a zigzag stitch on your regular sewing machine to secure it even more.

6. Makes Flat Seams Less Bulky

Sometimes you want your seams to be strong but not too bulky. A serger can create flat, strong seams with just three threads, which is perfect for things like leggings or lightweight fabrics. These seams are tough but won’t add extra bulk, so your clothes fit and feel better.

7. Great for Home Projects

If you’re sewing something for your home, like curtains, pillow covers, or even a quilt, or working with heavy-duty fabrics like canvas or upholstery material a serger will help you finish the edges and make everything look clean and professional. Not only does a serger make functional seams, but it can also create decorative ones! You can use colourful thread to add some flair to your projects—think fun edges on napkins, tablecloths, or even decorative pillows.

8. Saves Time

One of the best things about a serger is that it makes sewing so much faster as it trims, stitches, and finishes the edge all at once which is especially helpful if you’re working on big projects or need to sew lots of pieces quickly.

If your budget allows and you’re sewing often, it might be time to invest! A good serger can cost anywhere from $300 to $1,000+, so it’s worth considering how much you’ll use it before committing.