Insert the Boning
The corset is now ready for boning.
I always use precut bones for my corsets. They come in 1/2″ length increments, and frankly, cutting them myself is more time and trouble than I care to go to. I’d rather spend the time on detailing the corset. I used spring steel flats for this corset, but I highly recommend using spiral steels everywhere except at the center front and center back. Spring steel flats only bend in and out, but spiral steels will twist to smoothly follow all the curves of your corset. Ideally the bones will come as close as possible to your corset edging (usually 1/4″ or less binding around the top and bottom edges of the corset), but can be as far as about 1/2″ or 1.5cm from the edge and still serve their purpose. That means each individual bone needs to be 1/2″-1″ shorter than the length of its channel.
You always want your spring steel or spiral steel bones to be held tight within the corset. If they have wiggle-room, they will eventually wear holes in the corset you’ve worked so hard to make. One beautiful option is flossing, but if you don’t know how or don’t want to take the time, the boning can be secured using a sewing machine. All it takes is a couple back-and-forth stitches against the edge of the bone.
Remember to wear eye protection when stitching close to the boning. If you strike the boning with your sewing machine needle, the needle will break, not the bone.
Be sure to center the bones exactly where you want them in the channels before securing, and have spare machine needles handy in case you strike one of the bones. I always set the needle into the corset by hand (snugging it as close as possible to the end of the bone), and then stitch back and forth a few times with the machine. Trim the outside threads first, then tug the ends to the inside using the loose threads on the inside. Trim all loose threads from the inside.