Template

I made a template with a piece of 1/4" plywood in order to mass produce the hinging slots, 16 of them, with a large Dremel-type tool. This was hard to control and worked poorly for me so I reverted to chisel and carving tools and cut them by hand. As I got better at it, it took less time than I'd thought it would. After cutting, I drilled pilot holes to keep the screws from splitting the wood.