I was wondering if there is a rule of thumb on speed settings for different applications, wood types or type of bit when using a router?
John Swanson: Router bits under 1″ in diameter should be run at full speed. From 1″- 2″, use mid-range; and larger than 2″, low speed. Reduce your feed rate with the lower speed.
Carol Reed: The rule of thumb is the larger the diameter, the slower the RPM. Large diameter router bits usually come with a speed chart. The wood type doesn’t have much bearing on the RPM. How fast you move the wood into the bit does. This is called feed rate. Generally, burning is caused by a feed rate that is too slow and/or not smooth. Any hesitations or slowing of the feed rate will result in burn spots. Plan the depth of cut to allow you to make a smooth, moderately fast pass. For example, a large diameter panel-raising bit requires the slowest speed your router can deliver, usually 10,000 RPM or less. The depth of cut is limited to 1/8″ per pass. The feed rate is as fast and smooth as you can safely and comfortably make it. But do remember this is not a speed contest. A smooth pass is far more important, both for quality of cut and your safety.