What the CNC Does After the Saw
A saw makes straight cuts and a cnc does everything that is not straight, which is the division of labour described at countertop fabrication asheville nc thehistoryprofessor. Most of what a homeowner in Asheville notices about the finished countertop, the edge and the openings, is produced on this second machine rather than the first.
The Work It Takes On
Cutting an inside corner to a true radius. Running a profile wheel along the front edge. Drilling faucet holes and an air gap. Polishing the inside face of a sink cutout. Routing a drainage groove. It is a spindle on a gantry that changes its own tools, so a single program can move from a roughing pass to a finish pass without a person touching the piece.
Why Corners Get a Radius
A square inside corner concentrates stress at a single point, and a slab under any flex will crack from exactly there. A radius spreads that load along a curve. The tool cannot produce a sharp internal corner anyway, since a round cutter leaves a round corner, so the machine's limitation and the engineering requirement happen to agree.
Tool Paths and Finish
An edge is not cut in one pass. A roughing wheel removes the bulk, then progressively finer profile and polishing wheels bring the surface up to match the factory face of the slab. Rushing that sequence leaves a duller edge than the top, which is a defect people see without being able to name. On a mitred joint the machine also cuts the forty five degree face that the two pieces will be glued on.
What Still Needs a Person
Loading and clamping the piece square to the table. Setting the origin so the program lines up with the stone rather than with the machine. Watching the first cut on an expensive slab. And hand finishing anything the tooling cannot reach, which on a complicated top is more work than the program itself. Programming time is real and it is priced in. A repeat kitchen layout runs almost instantly, while a one off with curved returns and an inlay takes an operator an hour at the screen before any stone moves. That is part of why unusual shapes cost what they do.