How to make it

Fiber Optic Dress

Intermediate19 steps

Garment sewing and hand sewing. Shortcut: buy the dress, then start at Add the pouch

This dress started at a festival, when a bloom of fiber optic jellyfish floated toward me. They were so beautiful I knew I had to make the idea wearable. The fibers are from Ants on a Melon and the photos are by audreyobscura.

Read it through before you start: there's a big fail in the middle (a zipper I couldn't open once the fibers were on), and how I fixed it.

Guide by Natalie Walsh, fashion designer and former Instructables designer, shared with her permission. See the original on Instructables, comments and pattern files included.

What you need

Fiber Optic Costume KitOne 360-strand bundle, trimmed by you so you can layer the ends.
Get the kit
Dress fabricAbout 3 yards of something with body and a little stretch. I used a stretch woven blend.
Fusible interfacingAs much as your circle skirt. I used 1.5 yards of 45" wide.
TulleLots of it, or a ready-made tutu or three (any color, it only adds lift).
PatternDrape your own on a dress form or buy a V-neck circle-skirt pattern. Always sew a muslin first.
NotionsSewing machine and basics, boning (spiral for curves), invisible zipper, Velcro, clear thread for the fibers.

Short on sewing time? Buy a V-neck dress with a circle skirt and jump to Add the pouch.

Part 1 · Plan it

The design: Fiber Optic Dress build photo

Step 01

The design

One light source means a pouch at the center back. The straps carry the fibers from the back to the front and around the body to an even spread at the hips. For lift at the skirt I went low tech and stuffed it with tutus.

Note from Ants on a Melon

About the light

The light slides into a snug pouch at the center back, so plan that pouch, and how you'll reach the buttons and charge port, before you sew anything. Natalie built this dress on our first generation whip; the RGB Critter BT in today's kit charges over USB-C, runs about 7 hours and changes color from your phone.

Part 2 · Sew the bodice (from scratch)

Step 03

Cut out the pattern

Cut the front and back on the fold and two of everything else. Cut only one bodice layer to start so you can check the fit.

Step 04

First fitting

Sew the bodice and try it on. Always try it on: every step changes the fit, and sewing a seam is faster than ripping one out. Mine was roomy in the back, so I took those seams in.

Step 05

Second layer

Cut and sew the second layer with the fit changes. Sew the two together along the whole top edge and straps, leaving a gap where the straps meet the center back, turn it out and understitch the neckline. Try it on again; two layers fit tighter.

Step 06

Straps and pouch

Topstitch the straps to the shoulder, measure and set them into the back, and reinforce with a row or two of stitching. Make a snug pocket for the light at the center back.

Step 07

Add boning

Clip and press every seam flat first. Sew channels and cut each bone 1/2" short of its channel so it can move. Cap the ends so they don't poke through.

Part 3 · Skirt and zipper

Step 08

Make the circle skirt

Measure around the bottom of the bodice, divide by pi for the waist diameter and halve it for the radius. Mark that arc, then the hem arc (I used 20" for a bubble skirt). Two layers of fabric plus one of interfacing fused to the inner layer give it body without wrinkles.

Step 09

The zipper fail

I put the zipper in the side seam. Once I started laying fibers, I realized they would sew it shut. Lesson: plan the zipper and the fibers together. I moved the zipper to the center back.

Step 10

Fix it

Unpick the skirt and zipper, stabilize the center back with fusible seam tape and a zig zag either side, cut the opening, sew the side seam properly and re-bone it. Pin the skirt seam thoroughly before sewing it back on.

Step 11

Add the zipper

Measure the zipper from the top, bar tack where it ends and trim. Press an invisible zipper flatter first. With a zipper foot, sew close to the teeth without catching them.

Part 4 · Shape it

Step 12

Add the pouch

With the zipper at the back, the light pouch closes over it with a thin strip of Velcro on one side so you can still reach the zipper.

Step 13

Bubble the skirt

A bubble skirt reads as a jellyfish and adds lift. Pleat the skirt onto snug waist elastic with pins, matching notches at each quarter point, then sew it down.

Step 14

Make a tutu

Dense short layers and sparse long ones put the lift right at the waist. I wore two more tutus over it. More lift means more swing in the fibers.

Step 15

Dress done

The dress itself is finished and ready for light.

Part 5 · Add the light

Sew on the fibers: Fiber Optic Dress build photo

Step 16

Sew on the fibers

Comb the bundle into groups of 10 and tie each off with yarn. Sew them down along the back straps and shoulders in groups of 30 while they're dense. From the bust line, where they spread, sew each group down on its own. Tack them along the waist first to space them evenly. Slow, relaxing work: put a movie on.

Trim the fibers: Fiber Optic Dress build photo

Step 17

Trim the fibers

Light comes out wherever a fiber is cut, so trim like a layered haircut to spread the points of light. A nick or a scuff with sandpaper lets light out along the length too, if you want that look.