Milling Material Removal Rate and Spindle Power Calculator
Cubic centimetres of metal removed per minute by a milling cut, the power at the cutting edge, and the power the spindle motor needs, from the cut sizes, the feed and the specific cutting force.
Results
The dashed line marks the value you entered.
What this tool does
The material removal rate is simply the cross-section of the cut times the feed: radial width × axial depth × table feed. The power to do it is that rate multiplied by the specific cutting force kc and divided by 60 000, with the rate in cm³/min and kc in N/mm². Take kc from the tool maker's catalogue for your material — it is roughly 700–900 N/mm² for aluminium alloys and 1 500–3 000 for steels, and it rises when the chip is thin. Divide by the drive efficiency for the motor; a worn tool or a dull edge needs noticeably more.
Formula
MRR = ae × ap × vf (cm³/min = mm³/min ÷ 1000) · P_cutting = MRR × kc ÷ 60 000 (kW) · P_motor = P_cutting ÷ η
Variables
| Symbol | Meaning | Unit |
|---|---|---|
ae | Radial depth of cut (width of cut) | mm |
ap | Axial depth of cut | mm |
vf | Table feed rate | mm/min |
kc | Specific cutting force kc | N/mm² |
ef | Spindle drive efficiency | % |
MR | Material removal rate | cm³/min |
PC | Power at the cutting edge | kW |
PM | Power the spindle motor needs | kW |
Worked example
- Radial depth of cut (width of cut)6 mm
- Axial depth of cut10 mm
- Table feed rate800 mm/min
- Specific cutting force kc2000 N/mm²
- Spindle drive efficiency80 %
- Material removal rate48.00 cm³/min
- Power at the cutting edge1.60 kW
- Power the spindle motor needs2.00 kW
Limitations
- The result is an estimate based only on the values you type. Real situations often include factors this calculator does not know about.
- Coverage and consumption figures vary between products. Take the values from the manufacturer's datasheet for the product you are actually using.