How to Cut a Perfect Circle with a Router and Simple Jig
Cutting a large, perfectly round tabletop can be challenging with a band saw or jigsaw. Even with careful layout, it's difficult to maintain a consistent radius and achieve a smooth edge.
A simple router trammel jig makes the job much easier. This inexpensive circle-cutting guide turns your router into a precise tool for cutting round tabletops, shelves, and other circular woodworking projects.
Make a Simple Router Circle-Cutting Jig
A router trammel is essentially a long bar with a router mounted at one end and a pivot point at the other.
The pivot fits over a pin installed at the center of the workpiece, allowing the router to travel in a consistent circular path.
The distance from the pivot pin to the cutting edge of the router bit determines the radius of the finished circle. Adjusting that distance lets you cut circles in a variety of sizes.
For this tabletop, a straight router bit removes the waste as the trammel guides the router around the center point.
Prevent Tearout When Routing a Circle
One challenge when cutting circles in solid wood is routing across changing grain directions. As the bit travels around the circle, it can encounter end grain that may chip or tear out.
In this example, routing clockwise helps produce a cleaner edge. This technique, known as back-routing or climb cutting, changes how the bit engages the wood.
However, climb cutting can cause the router to pull unexpectedly. Use this technique only with a secure, rigid trammel setup and appropriate control. Conventional routing is generally the safer choice.
Make Multiple Shallow Passes
Rather than cutting through the tabletop in one pass, start with a shallow cut.
After completing the first circle, lower the router bit slightly and make another pass. Continue taking shallow passes until you've cut through the workpiece.
Keep the tabletop securely supported, including the waste portion, so nothing shifts as the final cut is completed.
The result is a smooth, accurately sized circular tabletop without the need for complicated templates or extensive edge sanding.
Featured Project: Swing-Leg Table
Put your router circle-cutting skills to work with our elegant Swing-Leg Table. This classic woodworking project features a round tabletop with drop leaves supported by swinging legs, giving you extra table space when you need it and a compact footprint when you don't. With its graceful design, clever construction, and practical features, it's a rewarding weekend project that combines traditional furniture-making techniques with everyday functionality.
