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When I bought my Brother 1034D serger, my first thoughts were, “What types of thread can I use for my serger? Which is the best serger thread to use? Can I use sewing machine thread?” I just wasn’t sure. I had acquired some very old SureLock serger thread from my Mom when her serger bit the dust, but I didn’t think using 20+-year-old serger thread was a great idea.
Sergers go through A LOT of thread, especially in the loopers, and I didn’t want to be wasting time or money with the wrong types. So, I did some research, read some serger basics books, and talked to experienced serger users to figure this question out. Turns out, there are SO many options of threads that will work for sergers. Decorative threads and even special serger yarns are fair game. It all depends on your intended use, budget, and decorative requirements. I’ve now expanded my collection of serger threads to include everyday serger threads and several decorative and specialized threads.
I want to help demystify the best serger thread types now and give you an idea of what you need to get started serging!
What Makes A Good Quality Serger Thread?
Not all serger threads are created equal! Make sure to choose a quality thread so you won’t have to worry about fraying, breaking, excess lint, or skipped stitches.
A good quality thread will feel smooth. It will have no lumps and minimal thread fibers protruding out of it. A hairy-looking thread is not one you want to run through your machine unless you want to be doing extra lint cleanup! And, if your thread is not uniform in thickness, you may end up with tension issues and breaking threads.
To see if your thread passes the quality test, take a small section of thread between two hands, and examine it for short fibers. The more short fibers, the lower quality thread, and the more lint in your machine as you serge.
What Color Serger Thread to Use?
Purchasing the rainbow of serger thread colors is not necessary. For example, on interior seams, there’s no need to purchase all 3 or 4 cones of identical colors. The most important thread to match the color of your fabric is the left needle thread as this is the only serger thread that shows when a seam stretches. Otherwise, you can choose a complementary neutral color for the looper and right needle threads.
GENERAL RULE: For dark fabrics, use black or gray as looper threads. For light fabrics, use white or beige. By buying cones of these “blendable” colors, you can save money and increase simplicity. Navy, red, and gold are also nice colors to have in cones but are less blendable. Once you’ve set your complementary looper treads, all you need to do is then change the left needle thread to match the fabric.
And lastly, when choosing a needle thread to match the fabric, always choose the darker (rather than lighter) thread color if you can’t find an exact match.
Best Serger Threads – Types Explained
Now, let’s get into the types of threads that will work well with a serger. This is by no means an exhaustive list, so let me know if you prefer a different type of thread so I can add it!
Serger Cone Thread
When no specific decorative project is in mind, serger cone thread is the best type of thread to choose for your serger. These cones come in huge yardages up to 10,000 yards and are economical, convenient, and last a long time. Serger thread is commonly core-spun polyester and is cross-wound on the cone. What cross-wound means is the thread unwinds from the top without the cone spinning. This makes for more even, smooth feeding through the serger when it is running at high speed.
The intended use of serger thread is for general serging in the needle and looper threads. It’s great for serging seams, edge finishes, and even some decorative applications.
In general, serger threads are finer than all-purpose sewing thread, thus reducing thread bulk at seams and increasing stitching smoothness. Quality serger thread will be uniform, smooth, and strong enough to withstand high serger stitching speeds! My favorite brands of serger cone thread are MaxiLock and SureLock. There are cheaper bulk options, but I’m used to these two brands.
Also, you can purchase cotton serger thread. It’s strong and soft, but as with all things 100% cotton, it shrinks. It also produces more lint for your machine due to the short fibers. This is why polyester serger cone thread is more widely preferred.
General-Purpose Thread or All-Purpose Thread
Can you use sewing machine thread on a serger? Yes, but you might want to consider other options for the loopers, at least.
All-purpose threads are the parallel-wound spools of thread you see at your craft store or even local Wal-Mart. These threads, typically used on sewing machines, will work on sergers also. They can be used for finishing fabric edges, decorative construction, and even seams. Common compositions include cotton, polyester, or cotton-covered polyester.
Sewing machine thread is strong and durable, but with how much thread sergers go through, you will constantly be replacing your thread spools! The great thing about all-purpose thread, though, is its variety of colors. What I like to do is use serger cone threads for the loopers and right needle and then use a matching all-purpose thread for the left needle needle thread when I’m sewing a seam.
My favorite type of sewing thread to use for my serger is Coats & Clark polyester thread. It’s available in a large selection of colors and at most craft stores.
Polyester or Rayon Embroidery Machine Thread
Embroidery machine threads are usually polyester or rayon and are known for their gorgeous luster and shine. That’s why they’re perfect for embroidery designs! These threads are cross-wound and will also work for serging. They’re a good choice for the needles when you can’t find a matching serger thread color when stitching seams.
When comparing polyester vs rayon embroidery threads, I prefer polyester when serging. Polyester threads are more colorfast and stronger than rayon threads. As such, rayon threads are not as well-suited to seams that will see heavy wear. In addition to providing the matching needle thread for seam construction, embroidery machine threads provide beautiful edge finishes and decorative effects. Rolled edges and flatlocking with embroidery thread produce beautiful results!
Nylon Sewing Thread
This very strong thread is used for sportswear, bags, and upholstery, for example. It’s not really a go-to thread for many serger users these days, though.
It can lose color and melt at very high temperatures, so make sure to use a press cloth when ironing and turn the temperature down. There is fusible thread, which is a nylon thread meant to melt! It provides a temporary bond when pressed with your iron. You can read more about all its uses here.
Woolly Nylon Thread (Textured Nylon)
Woolly Nylon is a fluffy thread that comes in solid, variegated, or metallic colors. When you pull Woolly Nylon thread taut, it shrinks in the middle. Letting it relax then puffs it back up. As such, it has good stretch and recovery. It also spreads out well and covers seams when doing a rolled hem or decorative ruffle finish. You can use it to stitch rolled edges, finish edges, or even seams on lingerie, knits, athletic wear, and swimsuits, for example.
One issue with Woolly Nylon thread is its soft, fuzzy texture makes it more difficult to thread. You may need to use a looper threader to get the thread where it needs to be. As it is nylon, remember to use low temperatures and a press cloth when ironing to decrease melting risk and keep the color from fading.
And lastly, while you could put it in all the serger threads, consider using it in just the loopers.
Monofilament Thread (Invisible Nylon Thread)
This is a transparent thread that comes in clear or smoke. It is a very fine, strong thread that can be used anywhere you want “invisible stitches.” I’m not a huge fan of monofilament thread, to be honest. It’s a pain in the rear because it tangles, breaks, and gets stuck everywhere. Some brands are better than others, and I’ve found the most personal success sewing with Sulky Invisible Thread. There is a definite learning curve to using invisible thread, though!
Silk thread is very expensive but adds shine and a luxurious feel to projects. To save money, only use it on threads that will show. Polyester and rayon threads are less expensive alternatives that still have that beautiful luster!
Types of Decorative of Serger Thread
The above serger threads are more popular for serging seams and finishing edges with only some decorative applications. Now, let’s talk about some of the best serger threads to use when looking to add a decorative effect to your project!
Metallic threads have a nylon or polyester core with metallic foil twisted around it. They have minimal stretch but are perfect for a shiny, decorative finish! These are especially pretty when flatlocking, edge stitching, or adding any decorative effect, really!
Hand Embroidery Floss
Yes, I’m talking about the floss you use when doing hand embroidery. Simply wind the embroidery floss onto a bobbin, thread it through your machine, and feed it through slowly as you stitch! This can produce a beautiful rolled hem, decorative hem, or flatlocked stitch. There are a lot of types of hand embroidery floss, so pick one that’s smooth, not too wide, and not too textured.
Serger yarn is a specialized cross-wound yarn for use in serging. It is very heavy so can really only be threaded in the loopers. Use both loopers for overlock and just the upper looper for a flatlock stitch or a heavy rolled edge. It makes a fun decorative edging and is common in finishing edges of fleece blankets and sewing sweater knits.
There are a few types of ribbon made specifically for serger use. You need to be very careful when feeding ribbon through your serger, but if you can successfully master this type of decorative serger thread, you can add fun finishes to so many projects!
Tips for Sewing With Decorative Serger Threads
1. If your project is one-sided, only use it on the upper looper, which is the thread on the right side of the fabric. For two-sided projects, use it on both loopers.
2. Check thread tension before sewing with a test scrap. Usually, you’ll want a slightly lower tension.
3. Pick an appropriate needle (for example, a metallic needle) and make sure the thread will pass through the eye before you spend time threading the machine.
4. Check thread weight compatibility with fabric type and weight.
5. Always check the label to know if the thread is machine washable, dryable, or able to be pressed.
6. Use a thread net for slippery decorative threads that fall off the spool and pool at the base. For example, rayon threads and metallic, decorative threads.
Serger Thread Weight Explained
Thread weight refers to the thickness of the serger thread. The higher the weight number, the thinner the thread. Generally, serger thread is 40 weight. However, you can purchase 50 weight or other weights, if needed.
Where to Purchase Serger Thread
While I like to purchase my serger cones from Amazon, Sewingmachinesplus.com, or Joann, sometimes local sewing shops have better variety and selection of more unusual serger threads and serger supplies. Thankfully I live in a huge metroplex with a great selection of small sewing businesses!
Best Serger Thread Types – Conclusion
To conclude, if you’re looking for the best serger thread for general use, start with polyester serger cone thread of good quality. Then, add other types of serger threads to your collection based on your serging needs. Happy serging!