You may have heard all the buzz around Colette Pattern‘s new men’s shirt, Negroni. One of the great construction details involves flat felled seams. Maybe you’ve used some other ways to finish seams before–could be pinking, serging, maybe even French seaming. You use different seam finishes for different projects, taking into account the fabric, the placement of the seam, etc. Sometimes referred to as a Lap Seam, Flat felled seams are normally associated with jeans–it’s a clean finish for a seam that is also extra secure because it’s double stitched. Leave it to Bernina to help make sewing these easier, by using foot # 70 or #71. #70 is best used for lightweight fabrics and creates an approximate 1/4″ seam. I used #71 for a 5/8″ seam allowance.
Start by laying your pieces wrong sides together and place one of the fabrics approximately 2.5/8″ apart. 2.5/8″??? Because we are sewing this twice, we need to distribute the seam allowance evenly. You can also gauge it using the foot; the opening in the foot is the right distance.
Using a straight stitch, you will want to adjust your needle position to the left. On the Bernina 430 I put it middle left, or two ticks to the left.
Next you’ll fold over the extended side to cover the top piece’s raw edge. I did a light finger press and then sewed a few stitches to secure it before lifting the fold up into the foot. Don’t forget to keep your needle down!
Stitch all the way down, guiding the fold through the center of the foot.
The point is to just barely catch the folded edge. If you have a hard time because the needle is too far left, shift the needle position. Then go ahead and press the folded sewn edge flat, hiding the raw edge.
Now to felled that flat seam! Back at the machine, you will again sew a few stitches to secure the folded edge down then raise your presser foot (with the needle down) and lift the folded edge through the foot. You are only guiding the folded edge as the machine sews an accurate top-stitch.
If you’ve ever tried sewing a flat felled seam “old-school” that involved trimming, folding, and eye-balling, this is WAY easier. And accurate!