I bought a cosplay for my sister and the obi was incredibly sad. It had no interfacing and the velcro was unreliable at best. This thing wouldn’t survive more than an hour at a con. So it’s time to modify this thing and make it nice and stable.

This cosplay came with a wide waistband secured with velcro in the back. Velcro gets caught on wigs and tears at the fibers, and with Nezuko’s long hair, that seemed like a recipe for disaster (in addition to all the issues the waistband already had). So it’s time to make this sad waistband into an obi.
This obi style is based on pre-tied obi. If you haven’t seen one of them, they’re more like wraps with strings tucked inside so they’re not visible. They wrap around your body, tie on at least the top (often the bottom), and make tying an obi look very easy. Because it’s faked. And we like to fake things as cosplayers.
You can find them with yukata (and sometimes kimono though those usually use an actual full obi) and they make cosplay dressing much more manageable. So let’s make an obi out of this sad sorry excuse for a waistband.
Skill level: late beginner
Cost: moderate. Depends on how much the purchased cosplay costs.
Materials:
- Purchased obi that velcros in the back and is folded over
- about 1y duck canvas. Color should match the obi or be lighter. For Nezuko’s obi, I used off-white
- Herringbone tape, shoestrings, or something that can support weight and not fray. 4 strings are needed, each must wrap around the body about 1.5x
Supplies and tools:
- Seam ripper
- Iron and ironing board, mat, or thick towel. Iron must have a polyester setting
- Fabric scissors
- Sewing machine with standard/universal needle
- Matching polyester thread
Disassembly
Before the transformation can even happen, the obi needs to be disassembled and the unneeded pieces removed. Start with the velcro, as that’s likely sewn through all the layers. Carefully wedge the seam ripper underneath the velcro and pull the threads, removing each piece of velcro. You can keep the velcro for other projects if desired.

After removing the velcro, it’s time to open the obi up. Start by ripping the seams along the outside edge where the velcro sat then move along the side, ripping the seam and unfolding the fabric.

Be careful when pulling the stitches, working one at a time. If your fabric is like mine, it might try to rip and snag right away. This obi fabric isn’t the best quality at all, but we’re going to make it awesome anyway.
Open the obi up but don’t iron it just yet. As the obi was likely factory pressed, there should be a fold through the center. To make the obi completely wrap-around, cut along this line to create two obi pieces.

Once the two pieces have been separated, iron the obi flat using the polyester setting on your iron so you don’t burn your fabric. Most purchased cosplays are pure polyester.
Adding support
We need to do something about how droopy this obi is, and duck canvas is exactly what we need. Your obi is likely going to be wider than the folded duck canvas, so open it up. To make the obi extra strong, you want to double the duck canvas. Fold the duck canvas down along the grainline to make a nice hotdog.
Place your original obi pieces on the duck canvas. Using them as a pattern, cut out two pieces of duck canvas for each obi piece.

Separate the canvas from the original obi. Sew the original obi together at the small side using about 1/4″ to 3/8″ seam allowance. Iron the seam open.

Sew the four pieces of duck canvas together at the small side, ironing this open as well. Two pieces of canvas should go on either side of the seam.
With wrong sides together, pin the obi to the canvas starting at the sewn center seam then pinning outward toward the edges. Leave the small edge open.

Once pinned, stitch a seam up each side at about 1/4″ to 3/8″ seam allowance. This ensures you have as much fabric as possible on the side you cut down the center of the obi where there was no seam allowance. And a small seam allowance is all you really need.
After sewing both sides, remove the pins and flip the fabric right side out by reaching inside the obi and pulling the fabric through the tube. Pull gently until the entire obi has been flipped right-side out.
Lay the new obi on the ironing board with the original obi fabric face down so that the duck canvas is facing upward. Iron the canvas on a cotton setting, pushing the edges flat before pressing them to get a nice seam.

For each open side, turn the fabric inward by about 1/4″ to 1/2″, about the length of your finger knuckle. Press this flat. this will form the finished edge in a bit.

Adding ties
To finish off the obi, we need some ties. It needs 4 ties. Each should be about 1.5x your waist size. The easiest way to measure it is to take the roll of herringbone tape and wrap it around your body 1.5 times. Once you’ve measured once, use that piece as a guide to cut your other ties to make a total of 4. Knot one end to prevent fraying.
The ties are placed at the top and bottom of each opening. Push the tape in about 1/2″ to 1″ inside the obi and pin it down in place. Once the ties are pinned, pin the rest of the opening as well to keep it from moving.

Once pinned, sew the open edge closed with a straight stitch, making sure to backstitch at each end for stability.

How to put on the obi
Now that you made the thing, how do you put it on?
You can do this yourself, though you may also want someone to help you out. Obis are made to be quite tight, so you want to wrap this tightly around your body. You can add an obi makuro, an obi pillow pad, to help flatten your back if you’re curvy like me, but this section only goes over how to wrap the obi without any padding.
As this obi originally came from a velcro belt, there’s overlap in the back. We want both sides to sit in the back and not be visible from the front of the kimono. Place one edge on the side back, about halfway between your side and your spine. Wrap the obi around yourself twice then pull the other side to your back.
If the obi is loose, you can pull on either edge to tighten it. The inner edge may not move as much, but if you need to tighten the inside, the inner edge is going to give you the best result.
Take the ties and tie them together in a bow, top tie to top tie and lower to lower.

With the ties secured, tuck them inside the obi, shifting them and pushing them down until they’re not visible at all. Do this for both front and back, top and bottom. You will only see them near the edge at the back.

Next tie the obijime, the cording. Depending on the design, this may tie in the front or back. Attach any obijime decorations as well.

To finish it off, add any bows to the obi. With the duck canvas, this obi can now support the pretied obi or the pinned bows needed to complete your look. And that’s it! you now have a nice strong obi that can support decorations and bows and last the con day without sagging.

I hope you enjoyed this little reconstruction tutorial! it’s a great way to make sure your store-bought obi will make it through the day and not end up a wrinkled, crumpled mess after an hour. And cons are, if nothing else, incredibly brutal on our cosplays.
This original obi lasted about 5 minutes on the dress form before drooping and sagging. After the modification, it’s been sitting on my dress form for about two weeks and hasn’t moved at all. Definitely passing the stress test.
Let me know what obis you restructure. @ me on social media so I can admire your hard work!