A Computer Numerical Control (CNC) router is part of a larger family of CNC machines that read machine language instructions to drive a mechanical system. This tool allows for precise, rapid machining of complex parts out of materials including metal, wood, foam, plastic, particle board, composites, and glass.
Here is an example of a CNC router machining aluminum.
The machine works by rotating a spindle with a cutting tool to shape, carve, or engrave a material resting below it on a cutting bed. The spindle rotates anywhere from 2,000 to 30,000 RPM, depending on the material. The work area can range from 12″ × 12″ for a hobbyist model to a full 4′ × 8′. CNC routers are commonly available in three-axis and five-axis models. With a three-axis model, objects can be modified in space: left and right, top to bottom, and forward and back. These are the X, Y, and Z planes. A five-axis model enables modification of an object on several axes, the extra two commonly known as the Q and B axes. Q refers to rotation and B refers to tilt.
This video shows the machine with a fourth-axis accessory shaping a column of wood.
Multiple stages of communication are usually required to materialize a design with a CNC router. This usually begins with CAD software that provides a user with tools for designing objects in two or three dimensions. Once the design file is set, Computer Aided Manufacturing (CAM) takes the CAD files and helps translate them into a series of steps for the machine to perform. G-Code, the standard for numerically controlled machines, is the language that the router actually follows to perform its operations.
Low end machines are intended for DIY use in light duty applications and typically cost between $10,00 and $30,000. Mid-range CNC machines range from $30,000 to $120,000, are built of heavier gauge steel or aluminum, and have a separate controller. High-end, three- to five-axis routers, which cost upwards of $120,000 are industrial strength and come with a full range of accessories like vacuum table and automatic tool changer. Setup costs often include shipping and training, not to mention the CAD software with which designs are created.
CNC machines have been in commercial use for a few decades now and it’s not hard to find suppliers online and regionally. K2 Devices, based in Southern California, seems to be a well-regarded, experienced dealer. Closer to New York City is Techno CNC Router Systems on Long Island and The CNC Router Store which sells used models. ShopBot Tools, in North Carolina, is another company that manufactures CNC routers in the States. It should also be noted that DIY CNC routers are increasingly common.
Below are a few places I found around New York that offer digital fabrication service for artists, designers, and students.
Located in New Rochelle, just north of the city, NYC CNC is a friendly and helpful small-scale operation. They’re interested primarily in projects at $500 and up, unless very simple. I spoke with Yanne who was also familiar with ITP.
This is a brooklyn-based studio founded by Columbia architecture graduates. They do a lot of work with designers and architects and specialize in solid surface manufacturing. They’re interested in projects at the $1,000+ level.
Prototope is in Tribeca.
They seem to focus on laser cutting but I’m awaiting correspondence about CNC millling. Joe at Prototope responded to my inquiry and indicated that they only do laser cutting.
For more on CNC routers, I highly recommend Alain Albert’s Understanding CNC Routers, where much of this information is drawn from. CNC Router Source was also helpful. This document is part of an overview of digital fabrication techniques collated on this page.