FEED AND SPEEDS CALCULATOR
Calculate feed and speed for CNC cutting tools with our free calculator below. All you need are the speed RPM, number of flutes, material, and tool diameter. CNC Router bits and CNC router tools are effective, only if used in the correct manner. If the material you need is not listed, let us know and we can help you find the right speed and feed for your piece.
CALCULATING CNC ROUTER TOOL FEEL RATES
The chip load is a measurement of the thickness of material removed by each cutting edge during a cut. This is a valuable piece of information that can then be used to calculate operating parameters for new setups. Chip loads are based on the material thickness of average size for cutting edge length of the tool. The calculation below does not apply to thicker material or tools with long cutting edge lengths. These feed rates are only a recommended starting point and may not accommodate all circumstances. Therefore, tooling damage may still occur, and the use of this calculator does not provide any warranty against tool breakage.
RPM SELECTION
The general operating RPM for tooling contained on this site is between 10,000 and 20,000 revolutions per minute. Usually, the higher the RPM, the better the surface finish becomes. However, the higher the RPM, the higher the friction generated between the tool and the workpiece. This friction is what creates the mechanical wear on the cutting edge. Using an RPM higher than your optimal feed rate causes re-cutting of the material and burning of the sharp cutting edge. Your goal is to select the lowest RPM possible for each application.
CHIP LOAD CHART
HOW TO USE A CHIP LOAD CHART
There are certain parameters to consider before determining any operating parameter if you want to achieve the required finish and accuracy. Chip load can be defined as the size or thickness of the chip that is removed with each flute per revolution. When the material is machined the cutter must revolve at a specific RPM and feed at a specific feed rate to achieve the proper Chip load. There are also several factors to be considered when choosing the proper RPM and feed rate.
The chip load is a measurement of the thickness of material removed by each cutting edge during a cut. This is a valuable piece of information that can then be used to calculate the exact parameters for each workpiece and material type.
Calculation are as follows: Chip Load = Feed Rate (inches per minute) / (RPM x number of flutes).
Example: Chip Load = 500 inches per minutes / (15,000 RPM x 2 flutes) Chip Load = .017″.
Chip loads are based on the material thickness of average size for the cutting edge length of the tool. These recommendations do not apply to thicker material or CNC cutting tools with long cutting-edge lengths. These chip loads are only a recommended starting point and are influenced by several other factors such as the rigidity of your workpiece, adequate vacuum to remove the cut waste, and may not accommodate all circumstances. Therefore, tooling damage may still occur, and the use of this chart does not warranty against tool breakage.
Read more about optimizing Solid Carbide Router Bits here.