Seam Finishes - Mock French and Flat Felled

False or Mock French Seam

By appearance, this finish is similar to the French Seam, but is constructed in a different way as follows:

Cut your seam allowance to 5/8”
With right sides together, sew a 5/8” seam
Press the seam flat (to set it) and then press it open
Press each seam allowance in half toward the middle
Match up the folded edges and baste or pin them together
To finish, edge stitch the folded edges together

The advantage to the Mock French seam is that it can be used on curved seams as well as straight ones.

The image to the left shows a sample Mock French Seam. The seam has been pressed the right. The construction seam (holding the two fabrics together) is the one on the left. The (incomplete) line of stitching on the right is the edge stitching of the folded edges. I apologize for the blurriness, my camera doesn't like closeups, apparently. But, I can't complain, neither do I.

Flat-Felled Seam

This seam is very commonly used on jackets and pants. It makes for a durable seam on light- and medium-weight fabrics. This finish encases the raw edges and when completed, gives the garment a decorative top stitched look after it sewn down. The process is as follows:

Cut your seam allowance to 5/8”
With wrong sides together, sew 5/8” seam
Press seam flat, then to one side
Trim the inside seam (the one on the bottom when the seam is to the side) allowance to 1/8”, turn the other seam allowance under 3/8”
Wrap the folded edge around the trimmed edge and pin or baste to the garment
Open the garment flat and stitch 1/4” from the original seam line

There is a also a mock or false variation using the preliminary steps of the Mock French Seam. To finish the Mock Flat Fell, instead of edge stitching the folded edges together, you lay the edges down on the fabric and edge stitch to the garment.

The image to the left shows a completed Flat-Felled Seam. In this picture I folded the fabric up so that you could see both the right and wrong sides of the seam. The portion showing on the top is flat while the portion on the bottom has a bump where the folded edge is sewn down.

I hope you enjoyed this brief introduction to seam finishes. If you have any questions, please feel free to contact me.

Happy Sewing!

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