Mark Mandell - Gone Round In Jersey
You're on the right track.
I, however, did a full circle (for a smooth cut), used 16 wedges to maximize the face grain on the outside, and cut those pieces sequentially from the same board so the grain was consistent (pretty much ). I then cut the 90° corner out of the donut. I used epoxy on the wedge joints, but pva and newsprint to glue them to the plywood "base".
You will also need a profile replicator to match the straight rails.