In general, "raw seams" are not something the average sewist aspires to. We spend so much time and effort trying to make the inside look just as nice as the outside that leaving a seam unfinished may feel... wrong. I'm here to bust the myth; raw and frayed seams can be purposeful and add a beautiful and unexpected design detail to your clothes and I encourage you to give them a try. While deconstructed finishes come in and out of fashion, I think they look great no matter what is happening with trends, and they work particularly well with knits.
I decided to give them a try when I saw a cool (and expensive) sweatshirt worn by my mother-in-law. Lynn is one of the most stylish women I know and I always want to steal her outfits (if I have the privilege of being this well-dressed in my 70s I'll know I'm doing something right). I loved how the simple shape felt special and unique just by leaving the seams raw and topstitched on the outside. They were a bit frayed here and there and looked weirdly amazing.
I basically recreated her sweatshirt exactly. The silhouette is almost exactly our Marine top (which incidentally Lynn modelled for us!) with the dropped shoulder, loose fit and flared sleeve. Marine has a wide boatneck and neck facing but I really wanted a classic crew neck, so I just traced the neckline from our Mile End sweatshirt to get the look I was after. I then used a very similar cream french terry from Core Fabrics (this fabric is now sold out unfortunately) and the dupe was on!
How to Prepare Deconstructed Seams
The key to sewing deconstructed or raw seams is to overlap them rather than sewing right sides together, and then topstitching in place using your choice of stitch. It will fray gently along the raw edge but still be secured by the topstitching.
In most cases, you'll need to trim your seam allowance down first. Why? If you overlap two 3/8" (10 mm) seams along the stitch line, the final width will be 3/4" wide – this will force you to topstitch quite far from the intended stitch line, and you'll have to trim the excess underneath. Here's a visual. As you can see, the seam below will be extra long, and the topstitching will be quite far from where the stitch line is intended to go.
Instead, you want your overlapping seams to be about 3/8" (13mm) total. This gives you room to handle and maneuver the pieces and still gives you enough of a raw edge to get that visible fraying we are after.
To accomplish this, you need to trim the seam allowance of every seam that will be exposed.
If the pattern has 3/8" (10 mm) seams:
If the pattern has a 3/8" (10 mm) seam like Marine or Mile End, you'll trim exactly half of the seam allowance down, or 3/16" (5 mm). Now when the seams are overlapping along the stitch line, you'll have a 3/8" (10 mm) exposed seam.
If the pattern has 5/8" (16 mm) seams:
If your seam allowance is 5/8" (16 mm), you'll trim slightly less than 1/2" (11 mm) to get that 3/16" (5mm) seam allowance. Make sense? Math is hard, I'm sorry!
How to Sew Raw Seams
Once your seams are trimmed, you're ready to start sewing. First, decide what pattern piece will be on top with the exposed edge, and which one will be on the bottom. In my case, I decided to make the sleeve the bottom piece and the bodice the top piece. To make it easier to overlap your seams evenly, baste along the bottom piece seam allowance at 3/8" (10 mm). You will use this basting stitch as a guide.
Next overlap the top piece and align the raw edge with your basting guideline. Pin in place along the seam.
Next, stitch down seam layers in place using a wide stitch, such as a zig zag, mock overlock, or coverstitch. Ensure you are catching both layers on either side of the stitch. I tried not to sew too close to the edge and left about 1/8" (3 mm) free so this would be free to fray*.
(*THINGS I NEVER THOUGHT I WOULD ENCOURAGE IN MY SEWING CAREER).
In some cases you may want to finish the hems, but to keep this sweatshirt deeply deconstructed, I decided to leave the hems raw as well. However, to prevent *too* much fraying and to add a little more detail, I sewed around the raw edges with my coverstitch as well. I love how it looks! I have also seen this deconstructed finish around neckbands as well, but I was a bit nervous about getting the band sewn in evenly so I did it the traditional way.
Of course after-care is a concern! I will be washing this on the gentle cycle and hanging to dry to minimize the amount of fraying, but you can always trim threads if they get unwieldy.
So that's it! What do you think of this raw seam finish? Are you interested in giving it a try?