A router table is a stationary woodworking

Woodworking

Woodworking is the process of building, making or carving something using wood.-History:Along with stone, mud, and animal parts, wood was one of the first materials worked by early humans. Microwear analysis of the Mousterian stone tools used by the Neanderthals show that many were used to work wood...

 machine in which a vertically oriented spindle

Spindle (tool)

In machine tools, a spindle is a rotating axis of the machine, which often has a shaft at its heart. The shaft itself is called a spindle, but also, in shop-floor practice, the word often is used metonymically to refer to the entire rotary unit, including not only the shaft itself, but its bearings...

 of a woodworking router protrudes from the machine table and can be spun at speeds typically between 3000 and 24,000 rpm. Cutter heads (router bits) may be mounted in the spindle chuck. As the workpiece is fed into the machine, the cutters mold a profile into it. The machine normally features a vertical fence

Fence

A fence is a freestanding structure designed to restrict or prevent movement across a boundary. It is generally distinguished from a wall by the lightness of its construction: a wall is usually restricted to such barriers made from solid brick or concrete, blocking vision as well as passage .Fences...

, against which the workpiece is guided to control the horizontal depth of cut.

Varieties

Router tables exist in three varieties:

• floor standing machines
• accessories bolted into table saw
  Table saw
  A table saw or sawbench is a woodworking tool consisting of a circular saw blade, mounted on an arbor, that is driven by an electric motor...
  
  s
• small bench
  Workbench (woodworking)
  A Workbench is a table used by woodworkers to hold workpieces while they are worked by other tools. There are many styles of woodworking benches, each reflecting the type of work to be done or the craftsman's way of working...
  
  -top machines

Use

Router tables are used in one of three ways. In all cases, an accessory is used to direct the workpiece.

1. A fence is used, with the router bit partially emerging from the fence. The workpiece is then moved against the fence, and the exposed portion of the router bit removes material from the workpiece.
2. No fence is used. A template is affixed to the workpiece, and a router bit with a ball bearing guide is used. The ball bearing guide bears against the template, and the router bit removes material from the workpiece so as to make the workpiece the same shape as the template.
3. A "pin router" accessory is used. A pin router accessory is an "over arm" that rises from one edge or corner of the router table, arcs over the table, and descends directly (coaxially) towards the spindle of the router. The end of the arm has a guide pin. A template (with an interior recess on the top face removed) is affixed to the workpiece, and the guide pin is lowered into this recess. The template is then moved against the pin, carrying the workpiece against the spinning router bit.

History

Router tables evolved as shop improvised tools. Individual woodworkers began taking routers, mounting them in an inverted position beneath a table, and using the routers' depth adjustment to raise the bit through a hole in the table surface.

Over time manufacturers began selling accessories (pre-made table tops, table legs, table inserts, fences, hold downs, vertical adjustment tools ("lifts"), etc.

Finally, manufacturers began selling complete packages, which ironically put them in the business of effectively selling wood shapers, the very tool that shop improvised router tables were created to stand in for.