Kerf port help
 

So I'm building a box for a sundown x12 and I've decided to go with kerfing the L shaped port in my box. So essentially the entire inner wall of the port and the front face of the box where the sub will mount will be one piece of wood. That being said, my measurements for the length of the port pieces and the front piece total up to be 64" (measured to outside of material which is 3/4 mdf or 3/4 Sande plywood) when I cut the 2 kerf bends in the wood, do I need to add any length to that piece? I assume no because the outside of the bend would still be the original length of the board. My thing is idk how and where to measure where to start the kerf at. Do I measure to the center of the bend and cut my lines evenly on both sides of said mark? Do I measure to beginning of the kerf? Halp. Front face piece is 26.5", first piece of port wall is 13.5 and the L piece of the port wall is 22.75.
https://cimg4.ibsrv.net/gimg/www.car...2939553894.jpg
https://cimg0.ibsrv.net/gimg/www.car...c111434f19.jpg
This is the end goal essentially

You need to determine what the radius will be for your curves, then start the Kerfs at that dimension once your front face length is achieved. So 3 inch radius started at a 26 inch face would make the perpendicular wall at 29 inches from the front corner. Does that make sense 🤔

So pie * radius squared ÷ 4 is how long you need to kerf for....lol sorry it's true tho