They took approximately 20 hours to manufacture. The outline was waterjet cut, the blade details were machined on a CNC, it was hand ground to shape, and then TIG welded together. The entire assembly was then nickel plated to create a mirror finish. The claws were used for a few cosplay photoshoots, and even tested by catching 50lb hay bales in the attached video. To create a sparking effect better than the original CGI in X-Men Origins, a car battery was connected to the claws, positive on one claw, negative on the other. When connecting the claws together, the car battery is short-circuited, resulting in big sparks! These sparks can draw anywhere from 200-300A, which the car battery can safely provide (rated for over 1000A cranking). The sparks are actually tiny bits of superheated metal coming from the claws – so the effect does slightly damage the props. Basically, the claws are acting like a resistor – becoming red hot, melting, and shooting little bits of molten metal away at high-speed for a glorious effect.