Seams & Stitching: A Simple Guide to Sewing Options
When making clothes, one of the most important things to think about is seams—the places where two pieces of fabric are sewn together. Seams are found everywhere on a garment, from where fabric panels meet to the finishing edges. The type of seam you choose will affect how the garment fits, stretches, and feels.
Choosing the right stitching method is crucial to ensuring your garment looks great and fits comfortably. Let’s explore the different stitching options you can use and how each one works, with some special exceptions for stretch fabrics!
What Are My Stitching Options?
There are many types of stitches you can use in garment making, and each one serves a specific purpose. Depending on the fabric and the type of garment, you’ll need to choose the right stitch to get the best result.
1. Straight Stitch
A straight stitch is the most basic stitch and is commonly used for seams that don’t need to stretch. It creates a single line of stitching that is strong but has no flexibility. Straight stitches are typically used in woven fabrics (non-stretch fabrics) and areas that don’t need to move or stretch much, like hems on dress pants, seams on woven shirts, or in quilting.
For stretchy fabrics like knits or spandex, the straight stitch is generally not recommended because it doesn't stretch with the fabric. If you use it on a stretchy garment, the seam might pop or break when the fabric stretches.
However, there are exceptions where you can use a straight stitch in stretchy garments:
- Straps and narrow areas: If you're sewing straps, shoulder seams, or other narrow areas where the fabric doesn't need to stretch much, a straight stitch can provide extra strength and structure.
- Sharp edges and cutouts: In some garments with specific design elements like sharp edges or cutouts, using a straight stitch can help keep the edges clean and precise, especially if you want to maintain a crisp look. Since these areas may not need to stretch, the straight stitch provides stability.
When to use it:
- For seams that don’t need to stretch, like in woven fabrics or hems on non-stretch fabrics.
- For straps or narrow seams in stretch fabrics that need stability.
- For sharp edges and cutouts in stretch garments where stretch isn’t required.
Pros:
- Strong and simple.
- Provides stability for certain areas of stretch garments, like straps and sharp edges.
- Works well for non-stretch fabrics.
Cons:
- No stretch, making it unsuitable for most areas of stretchy garments.
- Can break if used on fabric that stretches.
2. Zigzag Stitch
A zigzag stitch is a more flexible option compared to the straight stitch. Instead of the needle moving in a straight line, it zigzags from side to side, creating a wider and more flexible seam. The zigzag stitch has some give, which makes it a good choice for sewing stretch fabrics like knits or jersey. It’s also useful for finishing the edges of fabric to prevent fraying.
Because the stitch moves in a zigzag pattern, it’s better suited for seams that need to move or stretch with the garment. For example, if you're sewing an athletic top made of stretchy fabric, the zigzag stitch will stretch along with the fabric, preventing the seam from popping.
You can adjust the width and length of the zigzag to suit your project. A wider zigzag will give more stretch and coverage, while a smaller zigzag will be tighter and less stretchy. However, if you make the zigzag too wide, the seam can become weaker or lose some of its flexibility.
Best used for:
- Sewing stretchy fabrics like jersey, knit, and spandex.
- Finishing raw edges to prevent fraying.
- Sewing seams that need a little flexibility, like waistbands or armholes.
Pros:
- Flexible, making it a good choice for stretchy fabrics.
- Can prevent fraying when used to finish raw edges.
- Versatile, can be adjusted for different fabrics.
Cons:
- Can become bulky if the zigzag is too wide.
- Not as neat as other stitches like an overlock stitch.
3. Overlock (Serger) Stitch
The overlock stitch, also called the serger stitch, is commonly used in professional garment making, especially for stretch fabrics. A serger machine creates this stitch by wrapping the thread around the fabric’s edge while simultaneously cutting off the excess fabric. This creates a clean, finished edge that stretches with the fabric. Sergers use 3 to 5 threads to create a strong, durable seam with varying levels of stretch.
An overlock stitch is ideal for stretchy fabrics like knits, as it can stretch up to 400%, making it perfect for seams that need to move with the body. You’ll often find overlock stitches in t-shirts, leggings, swimsuits, and other stretchy garments.
One of the great things about the overlock stitch is that it trims the fabric as you sew, which keeps the seam neat and reduces bulk. However, this means you need to be careful with your seam allowance—if you don’t add enough, the serger might cut off too much fabric.
Best used for:
- Stretchy fabrics like knits, spandex, and jersey.
- Garments that need durable, flexible seams like activewear, swimwear, and t-shirts.
- Finishing raw edges neatly and cleanly.
Pros:
- Provides excellent stretch, making it ideal for stretchy fabrics.
- Creates a clean, professional finish by trimming the fabric edges.
- Strong and durable.
Cons:
- Requires a special serger machine.
- You need to be careful not to cut off too much fabric when sewing.
4. Cover Stitch
A cover stitch looks very neat on the outside, as it creates two or three straight rows of stitching on the top of the fabric while a zigzag stitch forms underneath. It’s commonly used for hemming stretchy fabrics, like t-shirts or leggings, because it provides stretch while still looking tidy and professional.
Cover stitches are also used to finish the edges of seams and to sew over seams that need to stretch, like on activewear or sports bras. They’re great for securing hems because the seam remains flat, and the fabric can still stretch without popping the stitches. Some cover stitch machines have a top looper, which makes the top and bottom stitches look the same, adding strength and giving a more polished look.
While a cover stitch machine is a bit of an investment, it’s worth it if you regularly sew stretchy garments that need to look professionally finished.
Best used for:
- Hems on stretchy garments like t-shirts and leggings.
- Finishing seams on activewear and sportswear.
- Creating durable, stretchy seams that look clean on both sides.
Pros:
- Provides a professional, polished finish.
- Strong and stretchy, great for sportswear and activewear.
- Can be used to topstitch elastic for a secure fit.
Cons:
- Requires a cover stitch machine.
- Not as versatile as a regular sewing machine or serger.
Seam Strength and Stretch
In stretchy garments, the strength of the seam is just as important as its flexibility. Seams should be strong enough to hold the fabric together but also allow the garment to stretch without breaking. For this reason, using the right thread is crucial. Polyester thread or other synthetic threads are best for stretchy garments because they’re more durable and resistant to things like chlorine, salt, and sweat.
In addition, using the right stitch type for the fabric is important. For stretchy fabrics, choose stitches like zigzag or overlock, which will stretch along with the fabric. If you’re working with stable fabrics, a straight stitch will provide the strength needed without worrying about stretch.
Conclusion
Understanding the different types of stitches and when to use them is essential for making clothes that fit well and last. Whether you’re sewing a basic seam with a straight stitch or using an overlock stitch for a stretchy garment, the stitching method you choose can make a big difference in the final result. Remember, while the straight stitch isn’t ideal for most stretch fabrics, there are exceptions where it can provide stability for certain areas, like straps or sharp edges. Take into consideration the type of fabric, the stretch, and the strength needed to choose the best seam for your garment!