The Shadow Project

cults3d

This posting is more about the process for making this light/shadow projection print, not the specific one I made. Though, if you are dating/married and your names start with A and M, this will work for you :) I was inspired by the stereographic projection design. In the process of figuring out how it was made, I realized it would work with any arbitrary 2D planar shape and 3D surface shell. You only need to know how to load your 2D shape into your designer, extrude it, and boolean subtract it from the shell. If you use blender (and probably others), make sure that you "Remove Doubles" after you scale the top to zero, so that it's actually a single point, instead 80 points with identical location. For reference, the "point" at the top is where the light source should go. You are essentially ray tracing the 2D projection" through the surface shell to get the exact cutout you need for the light to produce a nice square project. I added the bar at the top to make it easy to find where the light source should go (but it's short so it doesn't block the light when you actually put the light source there). This would work with just about any 2D design and any 3D shell surface, but you do have to be aware of how difficult it may be to print. And in some cases making sure that all pieces are connected (you'll notice I added a strip at the top of the A so that the "hole" would not be floating). You can project it onto a sphere, cylinder, or any arbitrary object, as long as your design program can do the boolean subtraction and you put the light source at the correct place.