Convertible (Infinity) dress

Have you made a convertible dress?
This type of dress has been around at least since the 1970’s


and here, without further ado, is how to make this variation, using ONE SEAM:
you need four pieces:  a circle for the skirt, two straps, and one piece for a “waist” band.  to decide how wide to make your straps, measure from the center of your bust to just under your arm.  to figure the length i just decided on 1.5 times my height, which i rounded to 90″ because that was easier to figure out than 64.75 X 1.5.  🙂  the skirt length is your choice.  the band needs to be a little longer than your waist measurement–i didn’t measure the length of my band, i just sewed it on and cut it off when i had gone all the way around the waist.

the next part sounds complicated but it is not.  turn your skirt inside out–you are going to sew from the INSIDE of the waist–which means you don’t need a free arm on your machine.  overlap the straps 3″-4″…

…and align the raw edges with the raw edge of the skirt waist.  then fold the band in half and lay it on top of the straps, the raw edges aligned with the skirt and strap edges.  you will have 5 layers of fabric on top of each other.  START SEWING AT THE OVERLAP.  (for now just ignore the fact that only one end of the band is in place).  when you get around to where you started sewing, overlap the band and cut the excess band, then finish sewing.  the band ends will not meet–they will overlap, but they will be hidden by the straps):

this is the one and only seam.
when the dress is done, it will look like this (that’s a 60″ measuring tape on the strap):

the whole thing took less than an hour from start to finish. (i didn’t do any edge finishes or even a hem on this dress because i was just playing around with the design but i definitely will be making more of these and i will do the niceties on subsequent versions.) here are a few other ways to wrap that i came up with this morning, and if you go to any of the sites i mentioned at the start of this post you can see dozens more ways to wear it.

the fabric i used is some polyester knit.  it has about 40% stretch on the cross.  i cut the straps so the stretch is parallel to the short ends, because i didn’t need them to stretch longer but i did need them to shape around my body.

if the fabric could be 4-way stretch and i think it would work just fine, but the straps might behave differently, depending on how much stretch was on the length.  i have also been asked if a non-stretch fabric would work, and you’d have to cut the skirt so that it was large enough in the waist to pull on, or put a zipper in it.

is how i figured out the length of the straps.  honestly, i just took a stab at it–i wasn’t sure the dress needed straps that long but figured i could always cut them shorter.   about the math:  i don’t do complicated math.  🙂  i just settled for a number that was close enough–if i were trying to build a space shuttle, i’d be a little more precise.

the band:  it’s primary purpose is to give the waist a finished back edge.  but it also serves as a channel for elastic, if you too prefer lazy math and end up with a waist that is a little too big.