Best routers are equipped with a speed adjustment capability that allows for speed modifications starting from around 8,000 to 24,000 revs per minute. Not all router bits can be safely or favourably run at the same speed. Like bigger router bits have more energy and potential to create forceful vibrations at higher speeds.
It’s actually important to understand what router speed really measures. “Revolutions per minute” is just a measure of the total number of times the bit makes an entire revolution in a stated time period and not a measure of the velocity at which the body and cutting surfaces of the bit are essentially travelling.
The outer perimeter of a 3” diameter bit is basically travelling noticeably quicker at 24,000 rpm than a 0.5″ straight bit’s cutting surface would be at the same shaft speed. Though it’s not possible to give a catalogue of speeds that will work fine in every situation.
Manufacturers often supply maximum free – running speeds for the router bits sold. The top speed for a fixed bit is the highest speed at which it can be safely operated, and may not be the best speed for the woodworking task.
In general, a quicker speed router bit is more desirable than a slower one, for the simplest reason that faster speed provides more precision cuts. Sharpened high-quality bits and the right feed rate go hand in hand with the bit speed making an accurate cut. Practice making cuts with a new bit until you’re able to provide a smooth, even feed rate that’s neither so quick that it creates a rough cut, or so slow that it ends in burn marks.
The information below offers speed guidelines for maximum, safe and free – running speed of bits of different diameters. This supplied for general reference only – manufacturer’s expert advice should be consulted:
Router Bit Diameter Maximum Speed Up to 1″ 22,000 – 24,000 rpm;
1″ to 2” 18,000 – 22,000 revs per minute;
2” to 2- ” 12,000 – 16,000 rpm;
2- ” to 3- half” 8,000 – 12,000 revs per minute.
There are more considerations for Router Bits – Router’s Horsepower, Feed Rate, Quality and Condition of the Bit and the Cutting Properties of the Material.