The idea is to be able to make a lithophane lamp out frame of two parts and easy to ship. I would print this in two rounds and with tree supports for the grooves. PLA 0.2mm. I've made a lot of gifts using this adjustable sized lithophane frame. I added a rotating part so that you can make the lithophane rotate on a bearing. 

I use these LEDS and Switch for the model. Typically drill a hole into the frame but it depends on your setup. If you'd like me to make you a color lithophane just PM me via my etsy link in my Bio or on here.