While a mock flat felled seam resembles a true flat felled seam, which is commonly found in jeans and requires specialized equipment, this method is simpler and can be achieved with a standard sewing machine.
- Start by placing the wrong sides of your fabric pieces together. The wrong side is usually less vibrant or slightly discolored compared to the right side.
- Place the fabric under the presser foot of your sewing machine. Align the edge with the 5/8 inch seam allowance marking on your machine.
- Sew a straight stitch along the fabric edge at the 5/8 inch seam allowance. When you reach the end of your seam, backstitch a few stitches to secure the seam. This prevents the seam from unraveling.
- Once you’ve finished stitching, trim the excess threads.
- Decide which side you want the seam to fold towards, as this will determine which seam allowance to trim. Typically, the bottom seam allowance is trimmed. Use your scissors to carefully trim this seam allowance down to about 1/4 inch. Ensure you cut straight and avoid cutting into the fabric itself.
- Lay the fabric down with the wrong side facing up. Take the longer seam allowance and fold it over the trimmed seam allowance, encasing it completely. This fold will help prevent the trimmed edge from fraying.
- To ensure the seam stays in place and looks neat, use an iron to press the folded seam down. This also helps to keep the width of the fold even and consistent along the seam.
- Place the fabric back under the presser foot, this time aligning the needle close to the folded edge of the seam. Begin stitching along the edge, backstitching at the start to secure your thread.
- As you sew, take care to keep the fold even and straight. You can pause periodically to adjust the fabric and ensure the stitching stays close to the fold.
- Once you reach the end of the seam, backstitch again to secure the stitching.
- After stitching, trim any loose threads.
- For a crisp, professional finish, press the seam flat with an iron. This helps the seam to lay flat and gives it a polished appearance.
You’ve successfully sewn a mock flat felled seam. From the front, it looks just like a traditional flat felled seam, but on the back, you’ll notice the difference where the stitching only penetrates through all layers of fabric on one side. While a true flat felled seam requires specialized machinery, this method gives you a similar finish suitable for a variety of garments, such as shirts.
How to Sew a Mock Flat Felled Seam Video Transcript
In this sewing tutorial we’re going to learn how to sew a mock flat felled seam, which is slightly different than a true flat felled seam or lap seam.
To get started we’ll go ahead and put the wrong sides of the fabric together. This is similar to setting up a french seam. You can tell the wrong sides of the fabric because they’re usually discolored a bit. Once you have the wrong sides together, place the fabric under the presser foot and we’re going to stitch a 5/8 inch seam allowance. Go ahead and stitch straight down at 5/8 of an inch and then when you get down to the bottom go ahead and reverse and back tack a little bit to hold the stitching in place.
Now we can trim our threads and get ready to prepare the mock flat felled seam. To make a mock flat felled seam we need to trim one of these seam allowances. I generally trim the one on the bottom because it’s easier but it does depend on which way you actually want to fold the seam so make sure you pay attention. Trim it in half to about a quarter inch or so and try to be straight and don’t cut into any of the other parts of the fabric. Now we’ll go ahead and lay the wrong sides of the fabric down and then we’re going to wrap the longer seam allowance around the other seam allowance that is now trimmed shorter and this will encase it and keep it from fraying.
You want to try to press this down and keep the width very equal and even so it looks nice and straight. Once you have this set you can go ahead and put it under your presser foot lining up right on the edge of that new folded seam. Stitch a bit then back stitch, then take a second to make sure everything is nice and straight and then continue top stitching to hold that mock flat-felled seam in place. As you go all the way down you can pause to readjust your fold to keep the width nice and consistent and looking sharp. You want to keep the stitching distance from each other even as well. Backstitch to keep everything in place.
Go ahead and trim your threads and now you have a mock flat felled seam. From the front it looks like a normal flat felled seam but on the back you can tell that the stitching only goes through all the layers of fabric on one side. On a true flat felled seam it would go all the way through. This is also called a lap seam and you see it in jeans and it takes a special machine to be able to do, particularly a double needle and double bobbin sewing machine, but this works really well too and can be used on shirts.
Once you’re done, you can go ahead and press this seam down with your iron and it will make everything lay nice and flat. Now you know how to sew a mock flat felled seam. Happy sewing everyone!