The pin router in action.

As CNC machines have become more prevalent, how much have they changed the building process?

“The Ballad of John Henry” looms large in the annals of American folklore. Versions of it have appeared in a number of narratives, usually referring to Henry as a “steel-driving” man who dies from the effort of defeating a steam drill machine designed to replace his ilk. Henry, who cuts holes in stone for dynamite with his hammer and chisel or alternately pounds railroad spikes, represents a way of life threatened by a powered machine.

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