How do I flatten geometry with a compound curve?

I have to model a boat on a real life example. It’s one that uses side planks that run from bow to stern. I want to cut the side wall planks using my IS 510 shopsabre CnC, I’m designing the boat in sketchup. I’ve just figured out how to make the planks have the correct compound curved plank.

I need advice on how to flatten my side plank so that I can export to my CnC program. I want to use sheet goods to make the planks. Does anyone know how I might go about it?