Woodworking is often referred to as the art of adding and subtracting. Since wood cannot be molded, items are made by adding and subtracting bits and pieces until you make the shape you want.

The electric router has become a modern replacement for chisels, a hammer and various planers. A router is one of the most desirable and versatile woodworking tools in use by woodworkers.

The secret to success for a router to accomplish a variety of woodworking design tasks is a selection of specialized bits. The bit determines the design or function of cuts made in wood.

Bits are manufactured from various materials and their quality can vary substantially. A quality bit will produce a quality job and poor quality bits can ruin a job even in the hands of pros.

The arbor is the shaft of a router bit and is attached to a shank at one end. The shank is the part of a router bit that allows the bit to attach to a router.

A collet is the part on a router that grips and holds any bit assembly to the router.

Everyone with a router should own eight basic bits. The recommended bits are; chamfer, edge-forming, flush trim, Joinery, rabbeting, rail and stile, raised panel and straight.

Chamfer bits are used to cut angles and shapes in the edges of wood. These bits are ideal for a weekend or hobby craftsperson to use when making decorative edgings.

Flush trim bits cut two joined pieces of material so that their edges match exactly. These bits are generally used to match a glued on veneer edge exactly or flush with the wood that it is glued to.

Rail and stile bits are used for making the special cuts required for building raised panel doors. Rail and stile bits are sold in pairs to create the required mirror image cuts required for end fitting.

Almost every router bit or bit set will have pictures of the shape it cuts on the packaging. Advice from your local bit supplier is also an invaluable source of help.

All router bits have a shank, a body and a tip, in addition, some have a ball bearing pilot to help guide a cut. The tip makes the cut, the body gives it shape and the shank connects the bit to the router.

You should push the shank all the way in and then pull it out about 1/8-inch before tightening to cut down on heat transfer from the bit to the router or vice versa.

Router shank diameters in the U.S. are either ¼ or ½ inch (6mm or 12 mm). There are routers that will only take ¼ inch shanks but with adapters you can use both sizes in a ½ inch router.

Router bits with a ½-inch shank will give smoother cuts with less vibration. These heavier shanks are less likely to snap or bend while making cuts.

Wet the end grain and let it sit for a minute or two before performing a cut. This will soften the wood and make your cuts smoother.

The speed range of most routers is 8,000 to 25,000 RPM. It is important to set the router to the proper speed because some bits require specific speeds for the best possible cut and for operator safety.

Manufactures instructions will usually give you a speed range and you can probably find recommendations online, however the best way to tweak to a final best speed is to practice on a scrap before you make your final cuts.

Most router bits are manufactured with either carbide or high-speed steel (HSS). HSS bits are much cheaper than carbide bits but HSS bits tend to become dull or damaged much faster and carbide bits generally last 20 times longer.

When choosing carbide router bits always inspect them carefully looking for smoothness, sturdy attachment of carbide tips, and a rust-free finish.