Trade education and workforce development are two initiatives we value highly here at Dunn Lumber, so it should come as no surprise that we have close ties with Seattle Central College's Wood Technology Center (WTC). With roots dating back to the early 1900s, WTC's history intersects with ours at Dunn Lumber at various points (our very own Ed Dunn Jr. took some classes at Edison), and we're proud to be connected with such an exemplary educational institution.
Throughout the episodes in this series, we'll be speaking with Dave Borgatti, a long-time faculty member at the WTC, about the center's history, program offering, and various topics in woodworking education. Dave got his start in woodworking as a boat builder in Portland, Oregon, for Schooner Creek Boat Works, and ended up at WTC as an instructor in 1992. Since then, Dave has helped countless students—from boat builders to carpenters and cabinetmakers—learn the woodworking craft.
A wood router is an incredibly versatile woodworking tool, partly due to the different types and sizes of router bits you can switch in and out of the tool to create different cuts.
If you’re unfamiliar with wood routers, head over to our Wood Routers 101 post first. In today’s conversation, Dave goes over the common types of routers bits and what they’re used for. Watch the video above or keep reading for a detailed recap.
What is a router bit?
Router bits come with a wide array of profiles to cut wood and other materials. A router bit differs from a drill bit in that it doesn’t cut on the tip but on its sides. These sides are called “flutes,” and most bits have two flutes. Some bits are piloted with bearings to ride against an edge or a pattern. Also, unlike drill bits, router bits' shanks only come in ¼” and ½” diameters and are held in the router’s collet.
Common router bits and their uses
Router bits are designed to shape edges, create joints, follow patterns, and plunge into the center of the workpiece. Since their flutes are tipped with tungsten carbide, they last a long time. Router bits can be used in handheld routers or router tables, where the router bit pokes vertically up through a stationary work surface. (These are great to have on a worksite as they don’t require clamping and let you have both hands on your material, maneuvering it around the router bit.
Below are some of the most common router bits.
Edge forming router bits
Routers are often used for edge forming. Two of the most popular edge-forming bits are:
- Roundover bits: Roundover, or “bull-nose”, bits come in many different diameters, including 1/16", 3/16", ⅛", and ¼". If you look at roundover bits from the side, you’ll notice their profiles have different shapes, which is the shape the router leaves on an edge.

- Chamfer bit: Chamfer bits create bevel cuts on the edge of your material and are often used on materials other than wood, like countertops. The deeper the bit is lowered from the router base, the larger the bevel. While most chamfer bits are 45º, other bevel angles are available.

Router bits for joinery
Joinery bits are mainly used for cutting adjoining notches into a material to create solid and durable joints.
- Rabbet bits: Rabbet bits are used to create one side of a rabbet joint (the other is simply a 90º cut). These bits often come with a number of interchangeable bearings that give different depths to accommodate any thickness of material.
Photo credit: Amana Tool - Dovetail bit: Another bit used for joinery is a dovetail bit. Dovetail bits have a V-shape that creates an interlocking joint with ease.
Photo credit: Amana Tool
Flush trim bits
Flush trim bits are used to trim material edges, making them flush with the edge of another material.
- Flush trim bit: Flush trim bits cut smoothly around a surface’s edge and can trim excess or overhanging material. They work well for duplicating patterns from a template, and are often used to trim shelf edging, veneer, or laminates.
Photo credit: Amana Tool
- Pattern bit: You can also find a pattern bit (sometimes called a pattern flush trim bit) that’s essentially a flush trim bit with the bearing at the top instead of the bottom. As the pattern bit goes around a pattern, it cuts whatever’s south of there.
Photo credit: Amana Tool
Straight bits
These bits plunge straight into the piece of wood to make grooves or inlays.
- Straight router bit: Straight bits are one of the most versatile bit types since they can cut right into the material, creating a square-shaped groove or dado (a groove across the wood grain), hollow out a space, go along the edge of wood to create a rabbet, or create channels for inlays. Some straight edges used in CNC machines have a piece of tungsten carbide that you can remove and flip over to use the second edge once the first edge is dull.
Photo credit: Amana Tool
How to avoid burning material when using a router
Router bits spin very fast (up to 30,000 RPM), so if they’re held in one place while cutting or go around a corner slowly, it’s common for the wood to burn slightly. This can be reduced by:
- Making sure the bit is sharp and clean.
- Lowering the speed if your router is equipped with a rheostat.
- When edge-forming, making the profile in two or three passes. Remember the old adage, “A router cuts best when it cuts least.”
Interested in learning more about woodworking and all its various tools? Check out our video about planers versus jointers, or dive deeper into how to use biscuit joiners with Biscuit Joiner 101: Part I and Part II.