Computer numerical control (CNC) routers are a class of machine shop equipment use to remove material from a specific location on a piece of wood or metal. There are different types of CNC routers for different materials, as each material has different strengths and weaknesses. Computer numerical control refers to the computer programming that is used to control and program the router. CNC routers are used to create patterns or cutouts as needed.
A CNC router is attached to a table and uses computer programming to remove material from a piece of wood or metal in a specific pattern or shape. The router is usually attached to a three or four speed motor system. The four motor systems provide additional speed and increased accuracy. A recessed door hinge in a door frame is an example of the type of work done by a router.
CNC routers designed for use with wood typically spin at a rate between 13,000 and 24,000 revolutions per minute (RPM). Different baseplates, templates or jigs are used to create a specific pattern in the wood. These items are installed in the tool holders, which are accessible through the spindle nose. A spindle nose tightens and releases to hold the tool used to cut the material.
Different models of CNC routers offer a wide range of tool holding and changing systems. These systems are designed to allow machinists to quickly switch the tool sets to meet to different requirements. The greater the flexibility, the faster the work will be completed.
When using a CNC router, it is important to understand the software that controls the router's movements. The actual blade depth and cutting location is controlled by the computer programming, and CNC machinists must become skilled with the software installed on the router. Specialized software is available for different materials, with tolerance and material feedback settings that can produce a higher quality output than other methods.
A wood router can also be used for plastics and other soft materials, as long as the speed is high enough. Metal routers have built in waste collection to safely collect excess material. When installing CNC routers, give some thought to the location of garbage bins to collect the waste material.
There are two methods used to secure materials when using CNC routers: suction based on pods or a vacuum system. Most routers offer only one method. Each method has specific applications where it would be more efficient.
Suction pods are typically used to hold onto the material so that is can be moved and manipulated as required. A suction based system is most practical when the product needs to be undercut. An undercut is when a slot or groove is created in solid material.
Spoil boards or cull sheets are another method of vacuum suction used on a low density table. This method allows the pieces to be placed anywhere on the table and held securely in place by the vacuum suction created under the table surface. This type of system is slightly more expensive than the suction pods, as the motor is required to generate a greater level of suction over a wider area.