https://www.cutoutandkeep.net/projects/french-seam-tutorial • Posted by Abby @ thingsforboys
French seams are a handy little skill to have in your repertoire. They're great for delicate fabrics because they enclose the raw edges inside two seams, so any fraying will stay hidden in the seam. And because you're sewing two seams, they make strong seams with a bit of insurance. They take a little extra time, but look lovely and neat on the wrong side and really add a professional finish. They work best on straight seams or seams with only a slight curve, such as the side seams of skirts, trousers or tops.
French seams are a handy little skill to have in your repertoire. They're great for delicate fabrics because they enclose the raw edges inside two seams, so any fraying will stay hidden in the seam. And because you're sewing two seams, they make strong seams with a bit of insurance. They take a little extra time, but look lovely and neat on the wrong side and really add a professional finish. They work best on straight seams or seams with only a slight curve, such as the side seams of skirts, trousers or tops.
To start off with, your given seam allowance needs to be split into two, giving a little bit for each part of the seam: - A 1.5cm seam allowance will be split into: 5mm for the first seam, then 1cm for the second - A 1cm seam allowance will be split into: 5mm for the first seam, then 5mm for the second - A 5/8" seam allowance will be split into: 1/4" for the first seam, then 3/8" for the second - A 1/2" seam allowance will be split into: 1/4" for the first seam, then 1/4" for the second
For the first seam, pin your pieces wrong sides together. This is opposite to the way you normally would. Sew your first seam, using the measurements above.
Press along the seam to set it. Then open out the fabric and press the seam to one side.
Now, fold the fabric over so that the right sides of the fabric are facing, and press the seam flat.
Open the fabric and trim the seam allowance down to 3mm (1/8"). It's easier to press the seam before you trim the seam allowance off, even though it might not seem like it.
Now you can sew the second seam. Your fabric will be right sides together (like normal). Sew your second seam, using the measurements above. Your raw seam is now hidden inside the second seam. Lovely!
Open out the fabric and press the seam to one side and you're done!