A few nice custom machined parts China images I found:
BrickArms MG42 prototype
Image by Dunechaser
German World War II soldier with prototype BrickArms MG42 machine gun and Ammo Chain.
The anatomy of a tunnel boring machine – a look inside the machine that will dig the SR 99 tunnel in Seattle
Image by WSDOT
How does a tunnel boring machine work? The answer, as you might expect, is complicated. The custom-built machine that will dig the SR 99 tunnel is designed specifically for the ground conditions beneath Seattle. This graphic illustrates a few of its more notable parts.
Check out this short video (or view on Youtube ) to see a similar machine in action. Tunneling will start in 2013. Learn more about Bertha, the SR 99 tunneling machine, at her webpage or follow her on Twitter @BerthaDigsSR99.