Straight Talk On Straight Bits

Here’s how to make the best choice for righteous routing

- Joe Hurst-Wajszczuk

Straight router bits aren’t as simple as you might think. Sure, some straight bits are more versatile than others. But the sampling shown here identifies important differences—in appearance, function, and cut quality. Whether you order your bits online or head to your favorite woodworking store to stock up, this information will help you get the best performance and value for your money.

Take a broad bite

With a downward-shearing cut and a wide cutting radius, a planer bit (aka “dado” bit) excels at routing shallow dadoes and leveling large surfaces like live-edged slabs. For woodworkers with large routers, planer bits are available up to 2" dia. Make sure to dial down your router’s speed to suit these big bits. CMT, 11⁄2 D × 5⁄8" CL, $31.99

Crisp at the top

Look for a down cut, spiral-fluted straight bit when your plunge-cut mortise or cavity needs to be free of surface tear out. This downward cutting action is great for inlay and banding work. But make sure to take shallow passes, and clean the cavity between passes to remove packed-in sawdust. Narrow-diameter bits are brittle, so use a larger bit whenever possible. Whiteside, 1⁄8 D × 1⁄2" CL, $18.44 Whiteside, 1⁄4 D × 1" CL, $18.44

Masterful mortising