Tell us about yourself!
I recently watched a U-Tube video on how to bend PVC. He capped one end, preheated some sand with a propane torch, poured it in-- to make it soft/pliable enough to bend it. My point is, "maybe" just putting unheated sand in the tubing would make it bendable without kinking. Interesting project, but like someone mentioned, I'd consider making something move--as in a piston or gears or??? Juss thinkin!