I though about making a sled like this for long time and finally made a prototype that we can use here in the park. This is made from some 3/4" plywood that was laying around and of the size I needed. I made it to swing up to 45 degrees and to make wedges up to 8" long.
It has a stop block on the swinging fence that will maintain the same length of wedges. The stop block is fastened down with a T- bolt that rides in the long T slot. I put in all the threaded inserts for clamping positions for different length wedges. When I make another one when I get home to Grand Rapids, I will make the hold down clamp also on a T bolt using that same T slot. I tried it out on some cedar that was laying around and it works pretty slick. I think it will come in handy for segmented bowls and platters using different angle cuts