What R Henrickson said. I'd probably just take a piece of cardboard and draw out the desired diameter and then cut a few test scraps and see if I can arrange them in some suitable pattern of evenly spaced pieces to the outer diameter of an inner circle - that would tell you roughly how many pieces and what length they need to be, and the tricky part would be getting all the holes (center and either end) of the "scissor" pieces to be precisely in the exact spot - Just a TINY bit off one way or another and the whole assembly wouldn't properly work without binding..... so you'd want to be sure you have a precisely accurate drill press and the skills to get things dead center, or perhaps you can have someone cut the parts CNC (which is probably what most of those pieces are done by nowadays)
I could easily get the rough pieces cut and sized, but I'd be guaranteed to fail at the hole drilling part - almost invariably my drill press would allow some amount of deviation on pieces (I've done some folding furniture which also requires pretty precise hole drilling but is a tad more forgiving off errors..) So I wouldn't try making one of those swifts myself.