One of my first 3D printed models, the ghost from the game Destiny. For fun I also a blue LED on the inside. This isn't my model but I am too happy to have a working printer (RigidBotBig) to not share!
Step 1: 3D Print
The model was downloaded from the thingiverse (426237)
Another great source for Destiny 3D models can be found here!
Print 2 copies of GhostBody.stl and one copy of GhostCenterOpen.stl. I found that nothing required support or anything fancy in the settings. btw, I used PLA but it doesnt actually matter what you print in.
Once the pieces are printed, I needed to melt away (since I didn't think to modify the files first) a hole to access the switch in the back of the center piece. I used a spare old soldering iron at low temperature to melt a hole for said switch. I then fitted the switch in place and melted some PLA around it to help secure it in place.
The pieces will be glued together eventually but we need to finish the electronics first!
The circuit is incredibly simple. All you need is a CR2032 battery along with a cell holder for it. Additionally, you will need an LED. If you use a LED with an operating voltage too far from 3.0V ~ 3.2V (the battery voltage) you will also need a resistor (this was not the case for me).
Simply wire up the circuit shown above and glue everything down to the bottom of the inside of the center ball (facing the open logo).
To help diffuse light I tacked (with my soldering iron) some mylar copy paper to the inside of the logo.
At this point you can glue (superglue) it all together and let it sit. The ball should still be able to roll around but fit tightly still inside the other pieces.
Hope you enjoyed this short ible :)