Router Bit Speed: Finding the Right RPM

Router bit speed matters more than most woodworkers realize. Running at the wrong RPM causes burns, chatter, and rough cuts.

The Rule

Larger diameter bits require slower speeds. A 1/4-inch straight bit runs fine at maximum RPM. A 3-inch raised panel bit needs the router dialed way down.

Speed Guidelines

Match bit diameter to these approximate speeds:

• Up to 1 inch diameter: 22,000-24,000 RPM
• 1 to 2 inches: 18,000-22,000 RPM
• 2 to 2.5 inches: 12,000-16,000 RPM
• 2.5 to 3.5 inches: 8,000-12,000 RPM

Signs of Wrong Speed

Too fast: Burning, excessive noise, vibration, bit deflection on thin cutters.

Too slow: Rough surface, visible mill marks, the router sounds labored and may stall.

Variable Speed Routers

Every shop needs at least one router with variable speed control. Fixed-speed routers work fine for small bits but limit your capacity for large profile work.

When buying bits over 1.5 inches diameter, check that your router adjusts low enough to run them safely.

Test cuts on scrap dial in the right setting. Start slower and increase speed until cuts come out clean without burning.