This was heavily inspired by the other brain gear shared here on Thingiverse. The other brain gears I've seen are printed all-at-once by a printer with soluable support material or such. I redesigned everything from the ground up such that it can be printed on my (hopefully coming soon) Makerbot. Assembly might not be possible and I'm thinking there will probably be some breakage.
I'll try to update and get rid of some of the bugs when I get my printer in.
You'll need to print 12 of the BG-1, 4 of the BG-2, 1 of the BG-3, and 1 of the BG-4-A (Assembly of the 12 necessary sleeves).