Len-
A minor detail but a 22" radius curve has 22.5o of curvature.
-- D
Oooops! Typing too fast and got an extra '2' in there.
You still chop the one piece into 2 pieces with 10deg arcs though.
Back when I was doing an early layout, I took a piece of poster board and drew 15, 18, 22in radius quarter circles on it with a yard stick "beam compass". Then I drew lines from the center point outward every 5deg of arc.
If I needed a 15deg 22in radius section, I'd lay it on the appropriate curve, line up the center line, and mark the cut location, and chop it off. I thought about adding additional arc lines, but it's easy enough to 'eyeball' the inbetween locations if you needed a 13deg arc section.
With plastic roadbed track I cut through the plastic with a 52TPI Zona saw, then snip the rails with a Xuron track cutter. This leaves minimal clean up to be done with a small file.
Len