Router bit speed are important to consider when cutting wood. The speed of the router bit will determine the quality of the cut. Using an incorrect speed for the router bit will lead to vibration in the tool and workpiece, tear-out of the wood, and the router bit may even become dull.
The diameter of the router bit impact the speed at which the bit should be rotated. The larger the diameter of the router bit, the more slower it will need to spin. Small router bit, like a 1/4-inch straight bit, will function best at high speeds.
How to Choose the Right Router Bit Speed
A two-inch router bit will require a lower rotational speed to avoid the increased heat and stress placed upon the bit due to it’s large diameter. The type of router bit will also impact the speed at which it are rotated. Straight bits are often used to cut dados and groove, and these bits can rotate at high speeds.
Ogee bits are used to create decorative edges on furniture piece, and these bits require lower speeds to avoid chipping the edge of the sawn wood. Spiral upcut bits tend to push sawdust out of the workpiece being cut, and these bits can reach higher speed than downcut bits. Spiral downcut bits push sawdust in the workpiece, protecting the workpiece from damage to the cutting surface of the workpiece.
However, you must take care to use the correct speed for these bits to avoid damaging the workpiece. The type of material being cut will change the speed of the router bit. Softwoods, like pine, allow for higher speed with the router bit.
Hardwoods, like oak and maple, will require slower speeds. Engineered wood products, like MDF and plywood, is abrasive to the router bit and require light cutting loads. Non-wood products, like acrylic allow for the router bit to generate heat that may melt the plastic when using high router bit speeds.
The shank size of the router bit will impact the stability of the bit at high speed. A 1/4-inch shank size bit will vibrate at high speed. A 1/2-inch shank size provide more stability for high speeds and is often used for professional task using the router.
The feed rate of the workpiece will impact the speed of the router bit. The feed rate should be matched to the bit speed; too slow a feed rate will burn the workpiece due to the buildup of heat. Too fast a feed rate will cause the router bit to stall and cause tear-out of the wood fiber.
The type of router that is used will also impact the speed allowed. Trim routers are used for small task and high speed. Plunge routers allow for variable speed control when plunging into the workpiece.
Table-mounted routers are the most stable and used for large project, and can handle the larger bit diameters that isnt possible with handheld routers. The material of the router bit will impact the heat that are allowed to build up during operation. Carbide-tipped router bit will allow for higher speeds and will last longer then steel bits.
Solid carbide bits are used in CNC machine. If there are any problem with the project or the router bit, there are certain step that can be used to adjust the speed of the router bit. If the wood fiber are burning, the bit speed should be decreased or the feed rate should be increased.
If the bit is dull, the bit must be sharpened as burning of the workpiece is caused by the dull bit. If the router is vibrating, the collet may be loose or the shank size may be too small for the router. If the wood fiber are tear-out, either the feed rate of the workpiece should be adjusted or the direction of the router bit should be changed.
