The channels I've patterned (and sewn) are barely 1/4 inch wide. In theory 3/16 inch plastic boning should fit, but I didn't have any handy. I did however have miles of 2.25 mm basket reed left over from another project. I swear not all the corsets will be boned with cane and reed, but since I haven't bought a single thing yet to make this one I thought I just keep sewing instead of driving to LA to buy supplies. Plus, two reeds measure 5/32 inch wide so they'll fit perfectly. Basket reed it is.
I measured and cut the reeds for the small in between channels and sanded the ends.
After they were slipped in place I could work on the long diagonal channels. Because they have a slight curve to them I made another template and taped it in place.
I couldn't slide boning into these channels when after they were sewn because the ends of the channels are against other seams. So I sewed that first seam, placed two trimmed reeds between the layers next to the seam, held them snug in place, and using a piping foot sewed right up against them.
The most difficult channels are finished. Once I sew the channels on the other pieces I can start assembling!