Basics: Repairing a Hem

April 13, 2013 by Colormusing 8 Comments

Because I’ve been making clothes nearly all my life, sometimes I forget that certain skills are not, in fact, second nature to everyone. Even so-called basic sewing techniques involve specific instructions, as I discovered this week when I had to fix a dress whose hem had started to come undone. Just photographing the various steps in the process of hand-sewing approximately 11″ was eye-opening— there’s a lot to this seemingly simple repair!

Here’s the situation: It’s a sheath dress in a substantial stable knit, meaning it has some give, but also holds its shape; this quality has to be taken into consideration, as I’ll show you in a bit. Somehow, between the last time I wore it and, well, now, the hem started unraveling between a side seam and the center back seam. (This is a ready-to-wear dress, originally hemmed with the commonly-used clear monofilament that doesn’t tend to wear very well.)

The hem of my dress coming undone. For such a small section to be restitched, it’s actually quite a project.

The first step (after admitting I have a hem problem, that is) is to determine the most appropriate hemming method. In this case, since I’m only repairing part of the hem, it makes sense to make the repaired part look as similar to the rest as possible, so I’ll hand-stitch an invisible hem. (And no, safety pins are not an option!)

Next, find a needle, sewing thread in a color as close to the fabric as possible, and scissors; you may also want pins to hold your hem in place as you sew. (I’m not using pins here, mostly so you can see what I’m doing with the stitches.) You’ll want a fine, sharp hand-sewing needle; these usually come in packages marked “sharps”, in various lengths.

After I had threaded my needle (using a double strand, meaning pull your thread through the needle and bring the 2 thread ends together), I realized that even “obvious” tasks like attaching your new thread could actually get more complicated. In this case, I first had to find the loose end of the thread from the original hem, where it had come undone. Then I could tie my new thread to the existing one, hopefully preventing more unraveling.

Tip: If your garment fabric is lightweight and/or finely woven, you may want to use a single strand of thread instead of doubling it.

Attaching new thread. In the top photo, you can (barely) see the original thread over my finger, to the right of the new thread; notice how much thinner the original thread looks, compared to my new double strand?

Tie the new thread to the old one (a basic square knot is perfect), placing the knot as close as possible to the place where you will start sewing. Then tuck the ends of the threads under the fabric that’s folded up to form the hem.

There are 2 steps to the invisible hemming technique. First, you’ll use your needle to pick up a single strand from the body of your garment (not the part that’s folded under), and second, you’ll anchor it by inserting the needle through the top edge of your hem allowance. Here’s what that looks like:

Invisible hem technique. At top, you can just barely see the strand I’ve picked up from the body fabric, followed by the anchor stitch in the edge of the hem allowance (bottom photo). You’ll repeat these 2 steps until your hem is complete.

Tip: It helps me to visualize the process as creating a triangle, starting from my new thread (just to the right of my thumb near the bottom of the photo above), making the top point of the triangle with the single strand, then completing it with the anchor stitch.

Tip: The reason for only picking up a single strand in the first step is to make your hem as close to invisible as it can be on the right side of your garment. There are some fabrics on which almost everything will show (silk charmeuse comes to mind), so it’s possible that this technique will not be ideal for your garment.

Because my dress is made from a knit fabric, as I sew, I’m occasionally giving my newly-stitched hem a gentle stretch, just to be sure there’s enough give in the stitches for normal wear.

Tip: Even if your fabric has no stretch, it’s still possible to pull your stitches too tightly, so doing this little test every so often is a good idea whenever you’re hemming.

The stretch test: Every 5 stitches or so, I’m giving my new hem a little stretch to make sure I’m not stitching too tightly to allow some give. In the bottom photo, after I let the fabric relax, you can see that there’s breathing room now between the stitches. (Don’t overdo this, though; you only need a little give.)

Tip: You’re probably wondering how closely you should space your stitches. Well, there’s not a magic formula for this (not that I’m aware of, anyway), but generally, I’d say aim for your anchor stitches to be about .75-1″ apart; this can vary depending on factors like the thickness of your fabric and the depth of your hem allowance, so experimentation is allowed!

Now, repeat the 2-step stitching process (including the stretch test, if applicable) until your new hem is complete. Then you’ll just need to tie off your thread and trim the ends.

Tip: If you’re doing a partial hem, like I’m doing with this dress, you will need to locate the other end of the original thread, so you can attach your sewing thread to it for the final knot, once you’re finished sewing, as shown in the photo below.

Final knot. It’s hard to see on this dark fabric, but I’ve tied my sewing thread to the original thread to fasten off my new hem, then trimmed the thread ends to about .5″ long.

Tip: Since the hem allowance is now closed, it’s harder to tuck the thread ends to the inside, so I usually just trim the ends as shown here. Just don’t trim them too close to the knot— leaving about .5″ or so should prevent the knot from unraveling. If your hem allowance is less than .5″, you could use a crochet hook, inserted between your stitches, to pull the thread ends to the inside.

Wow. I can’t begin to quantify the number of hems I’ve hand-sewn in my life, but this is really the first time I’ve paid this level of attention to what I’m doing while I was fixing this hem. Be sure to let me know if you have any questions about this hemming technique, or about any other issues you’re having with your clothes. As I said earlier, this project has been an eye-opener for me, and I hope it’s helpful for you too!