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Aside from the type of cutter used, the router’s versatility stems from one other main factor: the method used to guide the machine. In detailed woodworking, the router must be steered precisely into the workpiece to produce accurate results. There are several methods of achieving this.

Side fence

Most routers have a removable side fence; the novice woodworker should always use it, since it’s the easiest way to guide the router. However, this will only work on straight edges, and its use is limited by the length of the mounting rods. Adding a second fence is a great help when cutting mortises on the edge of lumber, because it will stop the router from rocking from side to side.

Trammel bar

To cut circles or arcs, a trammel bar or circle-cutting jig can be used. These are ideal for shaping circular tabletops. 22 Practical Weekend Projects for Woodworkers

Guidebush

Another very common method is to use a template in conjunction with a guidebush. A selection of bushes is provided with better makes of router. Guidebushes are screwed to the underside of the router, with the cutter protruding through the bush. The outer edge of the guide bush is then held against the template, usually shaped from a small piece of plywood or MDF, allowing repeated shapes to be cut with accuracy.

Bearing-guided cutters

These cutters are self-guiding and will run along the edge of a shaped workpiece without needing a fence or any additional guide. They produce consistent results. When using one, you must go around it in a counterclockwise direction. However, when molding an internal edge such as a frame, go in a clockwise direction. This means that you are feeding the work against the direction of bit rotation, making the machine bite into the lumber and push back against the operator. If you try to reverse these directions, the machine will be pulling away from you all the time. This makes the router dangerous and difficult to control, particularly if using large-diameter cutters.

Freehand

Some woodworkers can, after considerable practice, use a router freehand for operations such as carving letters or decorative features, much in the same way a jigsaw can be used. This is something that will help develop your control of the router. Use a V-groove cutter on a piece of scrap wood and make a shallow cut. Observe how the cutter tries to pull the router off-line and how the grain pattern affects this.

Guide batten

For cutting housings and grooves in the center of boards, a guide batten (or a pair of battens) clamped to the surface may be used. The router baseplate can be run along the side of the batten or sandwiched between a pair of battens, so there is no chance of it wandering off-line.