These are the 3D printed parts for holding the LED Board on my graduation mortar board, along with the light diffuser. This design has been printed and tested successfully on a MakerBot Replicator Dual, using PLA.
This was specifically created as a part of my "Control my Cap" project. You can learn more about it here: http://www.jeremyblum.com/portfolio/control-my-cap/
Print the cap base, and four of the cap clips. You will also need some additional hardware: