A multitude of router bits are available, allowing the user to create myriad profiles on moldings and edges.

With a fence clamped to the workpiece, you can square the edge by taking a full cut with a straight bit.

With a template and bearing guide, you can make an inlay and matching recess in the workpiece.

Push sticks keep hands away from the cutter.

Defining the Terms

Understanding each guide system requires understanding the four elements common to all: fence, guide, cutting circle and offset. The fence establishes the path — straight, curved or complex — that the bit will follow. The fence can be a separate straightedge; it can be the edge of workpiece itself, or it can be a template. The fence is always separate from the router. The guide is the part of the router that contacts the fence. It can be the edge of the router base plate, a base guide attached to the router base plate, a guide collar, a ball-bearing pilot mounted on the router bit or a trammel. The cutting circle is the largest diameter of the cut a bit makes, and the offset is the distance between the fence and the router’s cutting circle.

A good start to making safe and accurate cuts with a router is to understand how a router does its job. There are three elements to making cuts with a router: the router, the router bit and the guide system.

Routers are available from a variety of makers in a variety of models. The main differences have to do with size, power and whether they are fixed or plunge models.

Router bits are simple enough. What they cut is projected by their profile. How well a bit cuts generally depends on what you paid for it. The main difference between them is whether they are plain bits or have a guide bearing.

Guide systems are the most challenging element because they involve much more than a simple tool purchase. They require a clear understanding of the ways that a cut can be successfully made.

There are a total of seven guide systems. Four are applicable when the router is handheld and passed over the top of a workpiece clamped to a table or bench; three involve pushing the workpiece past the cutter with the router mounted under a table. Each guide system allows you to make a variety of cuts, so understanding them lets you choose the best setup for your equipment and the job at hand. Each of these guide systems will be covered in subsequent lessons.

Setup

There are two routing setups: You drive the router over a stationary workpiece, or you drive the workpiece over a table-mounted router.

Whatever system you employ, control is crucial to safety. With router-on-top guide systems, you must control the travel of the router. It must be held firmly so that contact between fence and guide is constant, and the workpiece must be securely fixed. With workpiece-on-top guide systems, you must control the travel of the workpiece. It must be held firmly to the bed and fence or pilot bit on the router table. The router must be securely mounted under the router table.

Control the Dust

Dust and chip collection also is crucial to safe and accurate operation of a router. Because router bits revolve at high speeds, they make very small chips when cutting solid wood. When cutting particleboard or MDF, the waste is a fine dust that is bad to breathe and makes a mess. This dust will collect everywhere, including on the work and on any jigs being used, and anything that comes between the guide and the fence reduces the accuracy of the cut.

You can alleviate these problems in two ways: remove as little waste as possible with the router, and exhaust and collect it. You often can reduce the amount of waste by removing bulk material with another machine. For example, if you are making parts with a curved edge, band saw the curve to 1/16" of the line. If you are making mortises, drill out the centers.

By whatever means, exhaust and collect all the waste you can as the cut proceeds. It’s worth the time and effort to rig any sort of exhaust system even if it’s far less than 100% effective.

And, as with the use of other power tools, it’s good practice to wear safety glasses to protect your eyes and ear plugs or other protection to guard your hearing.

Handheld Routing

The direction you push the router across the wood also is important for safety. It’s safest and most controlled to rout in a counter clockwise direction when routing the outside of a frame and in a clockwise direction when routing the inside of a frame. This way, you’re  feeding against the bit’s rotation, which helps hold the bit tight against the workpiece. Feeding with the bit’s rotation is called a climb cut; it requires greater operator control but can be used to achieve a smoother routed surface.