Together with selecting fabric, seam allowance width, or cutting pattern pieces, type of seam finishes is one of the things you decide on before starting any sewing project.
Before you start, consider the following:
- Type of fabric (knit, woven, non-woven)
- Woven fabric density
- Sheerness and transparency of fabric
- Fabric thickness
- Type of garment or sewing project
- Technologies available to you (type of sewing machine, overlocker (serger), pinking shears)
The most common seam finishes are:
- Unfinished edges
- Pinked edges (knit fabrics)
- Pinked edges (woven fabrics)
- Zig-zag stitch on a sewing machine
- Three step zig-zag stitch on a sewing machine
- Overlock seam on an overlock or serger
- Hand overcast (whip) seam
Unfinished edges
This is the simplest “finish”. Just cut the pattern piece with selected seam allowance and that’s it. Leave the raw edges as they are.
Use this “finish” for fabrics, that do not ravel at all. These are for example: knit fabrics, leather, synthetic (artificial) leather and non-woven fabrics.
If you plan to sew some leggings or sweat pants for your kids and expect A LOT OF WEAR AND TEAR resulting in significant damage (usually the knee areas), do not bother with finishing the edges of the fabric :).
Pinked edges (knit fabrics)
Pinking shears are the easiest tool for finishing edges of knit, non-woven fabrics. Use them for decorative seam or hem finishes (see the image above). To learn a little more about pinking shears, read my previous blog post.
Use pinked edges on fabrics, that do not ravel such as knit fabric, leather, artificial leather or non-woven fabrics. Apply pinking instead of unfinished (straight) edges when the straight edge of the seam allowance may result in a visible straight bump on the right side of the finished garment.
Pinked edges (woven fabrics)
Use this technique for really firmly woven fabrics that do not ravel badly. It is helpful if you do not have an overlock (serger) machine and for some reason do not want to use a zig-zag stitch option on your sewing machne.
The zig-zag cut is suitable for woven fabric made of both natural, artificial fibers or blends. However, DO NOT use it for sheer and loosely woven fabrics that ravel badly like organza, chiffon, georgette, voile, or muslin.
Zig-zag stitch on a sewing machine
Even the most basic sewing machine has a built-in zig-zag stitch that can be used to finish the seams of woven fabrics. It is a great technique to finish edges if you do not have an overlock seam on your sewing machine or a separate overlock or serger.
Use the simple zig-zag stitch for any woven fabric made of both natural or artificial fibres. Finishing edges of knit fabrics (like cotton jersey for example) might prove problematic. Test the stitch on a scrap of fabric. If you are unhappy with the result, try to lower the presser foot pressure. If you still don’t like the result, try a three-step zig-zag stitch.
To learn more about sewing with a simple zig-zag stitch, read this blog post.
Three step zig-zag stitch
Use a three step (also called a triple or multi step) zig-zag stitch for delicate fabrics, where a narrow zig-zag stitch would roll the fabric and a wide simple zig-zag stitch would create a tunnel on the fabric along the stitches (see the example below). To learn about this stitch in more detail, read this blog post.
Hand overcast (whip) stitch
This is a seam finish that is really soft and flat, but also extremely time consuming. Use this hand stitch if you do not have a sewing machine, do not want to use a sewing machine (because it is a really small project) or find hand sewing relaxing.
I also recommend you to read this blog post.
Overlock seam on an overlock or serger
Use overlocked seam fish to achieve a professional look of your final products. It can be used for any type of fabric. Depending on the qualities of the fabric (thickness, sheerness, type of wave), the stitch length, width and number of threads can be adjusted. For most fabrics use a three thread overlock seam finish (as in the image above). For heavier fabrics such as thick denim, you can use a four thread overlock seam like in the image below.
Most overlock machines have many stitch settings for various purposes. I will describe those in my next blog post.
