Have you ever sewn an unlined garment to see the horrible raw edges of fabric? It’s even worse if the fabric frays when you are wearing it – take the garment off and let the world just see the frayed fabric. Not only that, but unfinished seams really make the garment look homemade. One of the quickest ways to make a garment look directly from the shelf is to have finished seams. A french seam on store-bought clothes in one example of a well designed and made garment.
This is a tutorial on how to sew french seams. It is just one of the many ways to finish your seams professionally, however since it is so easy to do then they are a great option for beginner and advanced sewers alike.
What You Will Need
- Sewing machine,
- Iron, and
- Scissors (pinking shears are optional).
How To Sew a French Seam
Note, the following tutorial assumes that you want your seams to be hidden internally in a garment. Due to the decorative nature of french seams, you may actually wish to have the finished seam visible from the right side. If this is so, you can follow the tutorial and just reverse the right and wrong sides of the fabric when appropriate.
Determine the right and wrong sides of your fabric. In this tutorial I am using a cotton shantung – what’s unique about this material is that the right side has a very distinct shiny effect upon it’s right side.
Orientate your fabric so that the right sides are facing outwards. That’s right, away from each other, not the traditional right sides together. Align the raw edges together, and secure in place with pins.
Sew a straight stitch, following the raw edge of the fabric. Remove the pins as you sew so that you don’t break your needle. Due to the style of this seam, it is important that you sew less than the traditional 5/8″ seam allowance. Two good seam allowance options to use are 3/8″ or 1/4″. Keep a note of what seam allowance you have used in this step.
Trim the raw edges down. You can use your standard tailor’s shears, or for extra protection against frays you can use pinking shears.
If you want the seam to lay as flat as possible, then cut the layers in slightly different lengths. In most cases this alternating cut layers is not necessary.
Open the fabric so that the right side and seam are facing upwards. Using your iron, press the seam to one side – it does not matter which side you choose to press to. Do NOT press the seam open. Be sure that the iron is set to the appropriate heat and steam output for the type of fabric that you are using.
Turn the fabric over to the wrong side. Again press the seam flat.
Fold the fabric with right sides together. The stitching should be at the very edge of the fold. Again press the seam flat.
Pin the fabric in place.
Stitch the fabric from the wrong side using the remainder of the seam allowance. If you used the 3/8″ earlier, use a 2/8″ or 1/4″ seam allowance now. It’s important to know what seam allowance you used in step three in order to equal the appropriate seam allowance for your overall garment. If your finished product has too large or too small of a seam allowance it won’t fit as designed.
This step will effectively enclose and trap the raw edges of your fabric.
Press as sewn. Open up your fabric so that right side is down. Once again press the seam to one side. Note that it’s most common to press the fabric to the centre of the body.
Step 11 (Optional)
To help the seam lay flat, and to give a nice professional finish, topstitch the seam. It’s best to topstitch with the right side of the fabric facing upwards to ensure you stitch a nice straight line.
So here is the final result with the second row of topstitching.