I modeled this for some friends wanting to do a cosplay from the anime Attack on Titan. The lever moves, use an M6x25 bolt to pin it. In theory you could use it to pull a break line.
There is a hole on the bottom where you can attack a standard pneumatic fitting.
Printed on a Replicator 2 (its actually pretty big). Used Laywood3D filament and grey PLA.
Use supports on the handle and the top part, everything else should print without support. 2 grip files, one for each side.
Scaling was based off sketches found from the internetz here http://www.alexgian.com/wp/?p=72
Blade should be laser cut. Files soon..once I can actually cut some (machine downtime). I suppose you could easily hand cut too...but I'm lazy.