Router (woodworking)
[7] Further refinement produced the plunge router, invented by ELU (now part of DeWalt) in Germany around 1949.
Routing is a high speed process of cutting, trimming, and shaping wood, metal, plastic, and a variety of other materials.
Owing to inertia at these high speeds, the normal wood cutting mechanism of Type I chips cannot take place.
The cutter edge angle is blunt, approaching 90°, and so a Type III chip forms, with waste material produced as fine dust.
Cutter forces are high, so milling machines must be robust and rigid, usually substantial constructions of cast iron.
Holding a 3-horsepower router and turning it on without a soft-start is potentially dangerous, due to the torque of the motor.
For example, when shaping the edge of a fine table top, many users prefer a D handle, with variable speed, as it seems to permit better control and burning the wood can be minimized.
With the help of the multitude of jigs and various bits, they are capable of producing dovetails, mortises, and tenons, moldings of infinite varieties, dados, rabbets/rebates, raised-panel doors and frames, cutting circles, and so much more.
[citation needed] The tool usually consists of a base housing a vertically mounted universal electric motor with a collet on the end of its shaft.
Control of the router is derived from a handle or knob on each side of the device, or by the more recently developed "D-handle".
Without this, the varying reaction of the wood against the torque of the tool makes it impossible to control with the precision normally required.
This has benefits when working with smaller objects and makes some router operations safer to execute.
A router table may be fitted with a fence, fingerboards and other work-guiding accessories to make the operation safer and more accurate.
For smaller, lighter jobs, the router used in this way can be more convenient than the spindle moulder, with the task of set up being somewhat faster.
Router bits come in a large variety of designs to create either decorative effects or joinery aids.
Generally, they are classified as either high-speed steel (HSS) or carbide-tipped, however some recent innovations such as solid carbide bits provide even more variety for specialized tasks.
This reduces the chance that the workpiece is pushed too deeply into the bit (which would result in significant kickback from the cutting edge being unable to compensate).
Half-inch bits cost more but, being stiffer, are less prone to vibration (giving smoother cuts) and are less likely to break than the smaller sizes.
Failure to do so can cause permanent damage to either or both and can lead to the dangerous situation of the bit coming out of the collet during operation.
They are especially beneficial for home restoration projects, where production of the original trim and molding has been discontinued.
Sometimes complementary bits come in sets designed to facilitate the joinery used in frame and panel construction.
A tool similar to a router, but designed to hold smaller cutting bits—thereby making it easier to handle for small jobs—is a laminate trimmer.
A related tool, called a spindle moulder (UK) or shaper (North America), is used to hold larger cutter heads and can be used for deeper or larger-diameter cuts.
