Proton Pack Gearbox

UPDATE 19/7/2019: Specified position of WallBooster.

UPDATE 2/12/17. This part was used in the Ghostbusters Station 6 fan film. Check it out on youtube at https://www.youtube.com/watch?v=RHMUsQqLmRg

A full size, 3Dprintable gearbox for Ghostbuster Proton Pack based
on Steffan Otto's plans at:
http://www.gbfans.com/wiki/Stefan_Otto%27s_Prop_Plans

There are other versions of this, but they are very wasteful of plastic as the entire body needs to be filled.

Also,