How To Thread a Double Needle: Everything You Need to Know

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Cover Image: How To Thread a Double Needle: Everything You Need to Know

Have you ever wondered how to achieve those perfectly even double rows of stitching you see on store-bought garments? Are you looking to get more creative with your top-stitching? Most beginner sewers aren’t aware of all the handy sewing machine accessories that can be used to create professional-looking or otherwise unique finishing.

Double needles are some of the most effective and easy to use tools for taking your sewing projects to the next level. In this article, we’ll go over how to thread a double-needle and when to use it.

What is a Double Needle?

Professional dual needle sewing machine with white fabric

Double needles, or twin needles,  are exactly what they sound like: two needles attached to a single shank. One of the needles is usually slightly shorter than the other to allow the bobbin to catch both threads simultaneously.

Like regular needles, double-needles come in a variety of sizes. The size is listed as two distinct numbers—the first indicates the space between the needles, and the second indicates the actual needle size.

Keep in mind that the size of the twin needle you can use is usually limited by the width restrictions of your machine. Most machines will list any restrictions in the operating manual, but if you are unsure, you can always ask an associate at your local craft store.

When Should I Use a Twin Needle?

Sewing machine and a pink fabric

There are many benefits to working with twin needles. When working on garments, double stitching can be used to achieve the same professional look seen on hems, sleeves, and necklines of store-bought pieces.

In quilting and home decor, it can be used to create really stunning decorative stitches and designs, especially when working with two different accent colors at once. You can also use a needle to sew knit garments without a serger.

Supplies You’ll Need

Hand holding set of sewing machine needles on white background

  • A double needle: You can find a double-needle at any craft or sewing store. However, many machines come standard with a twin needle. Be sure to check your arsenal of sewing accessories before going out to purchase a new one.
  • Sewing Machine: All standard machines can accommodate a twin needle, as the process for installing one is the same as any regular needle. Advanced sewers looking to produce and sell professional-quality garments may want to consider investing in a machine more suitable for business purposes.
  • Two spools of thread: Double-needles require two separate spools of thread to be used at the same time. If you’re looking to create decorative topstitching, consider using spools of complementary and accenting colors. Just be sure that you are using the same type of thread for each, as working with threads of different tensions can create problems.

How to Thread a Double Needle

Step 1 Install the Double Needle

hands of a seamstress setting a needle in a sewing machine, close-up

Take out your regular needle and replace it with your twin needle. Because the two needles are attached to a single shaft, you will install them in exactly the same way as you would any ordinary needle.

Simply loosen the set screw and pull the old needle out of the opening. Insert the double-needle with the flat part of the shank facing away from yourself. Push it upwards until it reaches the stop point, and then tighten the set screw.

Step 2 Thread the Left Needle

Thread the left needle as you would normally, taking your upper thread from the spool holder and passing it through the machine according to the instructions on your particular model.

If your machine has a needle threader, be aware that you will need to manually pass the thread through the eye of the left needle. Using an automatic threader for twin needles can damage your sewing machine.

Step 3 Attaching the Second Spool

the spool pin is (generally located on the top of the sewing machine)

Next, you will attach the second spool of thread to the top of your machine. Some highly specialized machines will come with additional spool holders already attached. If your machine comes with this feature, lucky you!

If not, you will need to insert the extra spool pin that came with your machine onto the bobbin winder shaft. Then place your second spool of thread on the bobbin winder.

If your machine does not come with an extra spool pin, you can simply keep your second spool of thread in an empty mug or bowl off to the side of your machine and proceed the same way as if the spool were fully attached.

Step 4 Thread the Right Needle

close up shot of a hand inserting a thread into the needle

To thread the right needle, you will begin the same way you would normally, taking the upper thread from the second spool and passing it through your machine’s specific upper thread guide.

The only difference is that this time you won’t pass the thread through the needle bar thread guide nearest the eye of the needle. You will still pass the thread through the eye of the right needle; you will simply skip the final bar thread guide.

In the end, you should have both needles threaded, with the left thread securely tucked behind the bar guide and the right thread hanging loosely in front of it.

Step 5 Start Sewing

How Does a Sewing Machine Work

Now you’re ready to start sewing! Select the stitch you want to use and sew with the right side of your fabric facing up. Unlike seaming or other aspects of garment construction that require you to sew with the right sides facing, double stitching almost always has the right side of the fabric facing up to achieve decorative detail.

Some advanced machines with electronic monitors may have a specific selection key for twin needles. Others will simply require you to select a stitch using the stitch dial. If you aren’t sure which stitches your machine can accommodate for twin needles, consult the user manual for guidance.


Twin needles are extremely easy to use, and once you learn how to thread them, you can do all sorts of creative top-stitching and perfectly parallel hemlines.

Did you enjoy this tutorial? Let me know what you think in the comments and be sure to share the article with other sewers, designers, and crafters!

Looking for a tutorial on how to thread a single needle instead? Check our guide here.