It amazes me how I can knock out a mock-up in an afternoon, but the real deal takes forever. But at last the channels are all sewn.
It may have gone quicker if I had used disappearing ink, or chalk, to mark all the channels instead of my pins and tape system. Maybe next time? I'll have to do tests.
The next steps are, knot all the loose ends, attach the shoulder straps, put in the grommets, sew the panels together, measure and slide the reeds in, then bind the edges. Whew, I'm out of breath. My goal is to be sewing binding by the end of next week.