Calculator
Formula Used
Spindle speed (RPM)
- Metric:
RPM = (V × 1000) / (π × D)where V is m/min and D is mm. - Imperial:
RPM = (SFM × 12) / (π × D)where D is inches.
Feed rate
Feed = fz × Z × RPM- fz = feed per tooth, Z = tooth count.
Time estimation
Time per cut = (Cut length / Feed) × 60 × (100 / Efficiency)- Efficiency above 100% represents unusually smooth production.
How to Use This Calculator
- Select your unit system and the workpiece material.
- Enter blade diameter, tooth count, and feed per tooth.
- Confirm the cutting speed preset, or override it.
- Add cut length, number of cuts, and efficiency factor.
- Press Calculate to view RPM, feed, and time estimates.
- Use CSV or PDF exports to standardize shop settings.
Example Data Table
| Material | Blade Diameter | Cutting Speed | Teeth | Feed/Tooth | Estimated RPM | Estimated Feed |
|---|---|---|---|---|---|---|
| Mild Steel | 350 mm | 25 m/min | 120 | 0.04 mm | ≈ 23 rpm | ≈ 110 mm/min |
| Stainless | 315 mm | 15 m/min | 100 | 0.03 mm | ≈ 15 rpm | ≈ 45 mm/min |
| Aluminum | 350 mm | 120 m/min | 100 | 0.06 mm | ≈ 109 rpm | ≈ 654 mm/min |
Example values are illustrative; verify machine limits and blade ratings.
Measure carefully, validate limits, and cut safer every shift.