Get a handle on using a handheld router.

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Group of routers
jim heavey router.jpg

Often thought of only for its ability to add a decorative edge to any surface, a router can also easily create strong and attractive joinery or eye-catching inlays. Once you know the basics of its operation, you open up a world of uses.

A map of the router

In a router, a motor spins a collet that grips the shank of a router bit. We'll talk more about collets and bits in, er, a bit.

Routers come in one of two base styles: fixed, where you set the cutting depth once and lock it in for the task; and plunge, where two spring-loaded rods support the motor and allow for lowering and raising the spinning bit into and out of a workpiece. This plunging action makes it easier to start a cut in the middle of a field, such as for a stopped dado. Many manufacturers offer both bases in a kit with a single router motor that swaps between them [Photo A, below].

Labeling parts of a router.
Kits provide a less expensive option than purchasing two separate routers. Swap the motor between the fixed base and the plunge base depending on the job.

Routers range in power from 1-hp trim routers to 2- and 2 14 -hp midsize routers, and powerful 3-plus-hp machines. To further add to the variety available, many manufacturers now offer battery-powered models [Photo B, below]. This gives you a truly portable tool for use in the shop or on a job site.

Different types of routers.
Big routers have the power to spin large bits through a cut. Smaller models can be operated one-handed.
Different size of collects.
Collets match bit-shank diameters, the most common being 1⁄4" and 1⁄2". Not all routers accept 1⁄2" bits, and some use a reducer to fit 1⁄4" bits in a 1⁄2" collet.

In all routers, a collet, tightened by a wrench, compresses around the bit shank to hold it in place [ Photo C, above]. To secure a bit in the collet, insert it until it bottoms out, then raise it to expose about 18 " of the shaft above the collet. Then tighten the collet [Photos D, E, below].

Using wrenches to tighten collet.
Some routers require one wrench to grip the spindle and a second wrench to tighten the collet. Squeezing the wrenches with one hand allows steadying the motor with the other.
Collet locked with one wrench.
A collet lock prevents the spindle from turning so you can tighten the collet using only one wrench.

A bit about bits

At the heart of routing is the bit [Photo F, below], with cutters of either high-speed steel or carbide. High-speed steel bits cost less but dull quicker than carbide bits.

1/4" and 1/2" shanks on bits.
In general, smaller-diameter bits have 1⁄4" shanks. A 1⁄2" shank adds cost to the bit but provides increased strength and stability—critical when using large-diameter bits.

A bit for shaping a workpiece edge [Photo G series, below] or following a template secured to the workpiece has a bearing at the end. The bit spins inside the bearing, reducing friction, which causes burn marks.

Bearings riding alongs edge of workpiece.

Setting up for a cut

After securing the bit in the router, follow these steps before hitting the "on" switch. Though early routers ran at fixed speeds around 25,000 rpm, most newer models come with variable-speed motors [Photo H, below]. Run small-diameter bits at high speeds; use slower speeds for large-diameter bits.

Showing variable speed control.
Variable speed allows matching the motor speed to the bit diameter for safe operation and the best results.

Next, set the cutting depth. A good rule of thumb is to remove no more than 316 " in any one cut. This reduces strain on the bit and motor, and reduces chip-out on the workpiece [Stop chip-out, below].

Stop chip-out 

Routing across end grain can cause chip-out at the end of the cut [ Photo I, below]. A pass along the adjacent edge removes minor chip-out [Photo J, following]. To prevent chip-out from happening in the first place, back up the cut [Photo K, beneath]. Use this technique if you won't be routing a profile on the adjacent edge.

Chip-out from router tear.
As the bit rotates out of the workpiece, it tears unsupported wood fibers along the adjacent edge. Stringy woods, such as oak, prove especially prone to chip-out.
Edge with no routed chip out.
Routing the edge cuts away the torn fibers, leaving a smooth profile on the edge and end. So for edge treatments, rout end grain first, and edge grain last.
Clamped scrap flushed with the end of the board.
Clamp a scrap the same thickness as the workpiece flush with the end of the board. This supports the fibers along the edge, resulting in a clean corner.

Before touching the bit to wood, you need to understand how bit rotation affects the direction you move the router. In a handheld router, the bit spins clockwise when viewed from above. When routing an edge, moving the router counterclockwise around the workpiece helps keep the bit bearing against the wood edge as you push the router along [Drawing 1, below].

Showing direction of router cut.

When routing clockwise—called climb-cutting—the bit bites into the edge and pulls the router along, like a car tire when you mash the gas pedal. Because deep cuts increase this tendency, resulting in ragged cuts, only climb-cut with very shallow depth, and only when necessary [Drawing 2, below].

Climb cutting illustration.

Routing direction confuses even experienced users, especially when it comes to routing the inside edges of a frame. A simple way to think of it: Look at each member of the frame as a single workpiece, and begin routing counterclockwise around it [Drawing 3, below]. You'll automatically start off in the correct direction.

Directions showing routing around a frame.

Now that you know which way to move, follow the steps in Photos L­­—N, below, to rout an edge.

Starting to router edge board.

(Above) start with the router base on the workpiece, and the bit away from the wood. Turn the router on, grip both handles, and push the bit into the wood until the bearing makes contact as you also begin moving the router along the edge. You should hear the motor's pitch change slightly as it works. That's just what you want.

Bearing drifts away from edge.

Keep the router base pressed against the top of the workpiece. Don't worry if the bearing drifts away from the edge at times (above); you can clean up inconsistencies with another pass (below).

Cleaning edge with a second pass.

Proper feed speed is something you develop with experience, and it varies with wood species, so practice on scrap for your first passes. Too fast, and you increase chances of chip-out. Too slow, and you may burn the edge [Photo O, below]. Slowing as you prepare to turn a corner is a common cause of burn marks.

Showing burns on routed piece.
Burn marks can be difficult to remove. Changing your stance or grip as you rout can cause a pause, resulting in a burn.

If you need to rout deeper than 316 " using a fixed-base router, take several passes, lowering the bit no more than 316 " between each pass to reach the final depth [Photo P, below]. A plunge router offers an easier way, using the depth-stop turret [Photos Q, R, following].

Showing 3 routing passes.
Routing this deep profile in three progressively deeper passes resulted in a smooth edge with no burning or chip-out.
Start of a three step cut.
For a three-step cut, first plunge the bit to the final depth. Rotate the turret to one of its lower steps and adjust the depth-stop rod to contact it.
Start of a three step cut.
For a three-step cut, first plunge the bit to the final depth. Rotate the turret to one of its lower steps and adjust the depth-stop rod to contact it.
Rotating turret two steps.
Rotate the turret two steps to a higher step, and make the first cut. Then, rotate the turret and make a deeper pass. One more pass at the original turret step will complete the profile.

Get guidance

Using a bit without a bearing requires some method of guiding the router. Mount an edge guide to the router base [Photo S, below], or clamp a straightedge to the workpiece [Photo T, following].

An edge guide indexes the bit.
An edge guide indexes the bit a set distance from the workpiece edge, creating a cut parallel to the edge.
Ride the router base against a straightedge to cut a dado or groove.
Ride the router base against a straightedge to cut a dado or groove in a workpiece.

Mastering the use of a router opens up a world of decorative project possibilities as well as time-tested and functional joinery solutions.