Drill Spindle Speed Chart
This drill spindle speed chart lists HSS drill surface-speed ranges, feed-per-revolution ranges, and the RPM formula for drill presses and CNC drilling.
HSS drill speed chart
| Material | Recommended SFM | Source table |
|---|---|---|
| Aluminum and its alloys | 200-300 | Norseman HSS drill chart |
| Brass and bronze, ordinary | 150-300 | Norseman HSS drill chart |
| High tensile bronze | 70-150 | Norseman HSS drill chart |
| Zinc-base die casting | 300-400 | Norseman HSS drill chart |
| Cast iron, soft | 75-125 | Norseman HSS drill chart |
| Cast iron, medium hard | 50-100 | Norseman HSS drill chart |
| Cast iron, hard chilled | 10-20 | Norseman HSS drill chart |
| Magnesium and alloys | 250-400 | Norseman HSS drill chart |
| Monel / high nickel / stainless | 30-50 | Norseman HSS drill chart |
| Plastics or similar materials | 100-300 | Norseman HSS drill chart |
Recommended feed per revolution by drill diameter
| Drill diameter | Feed, in/rev |
|---|---|
| Under 1/8" | .001 to .003 |
| 1/8" to 1/4" | .002 to .006 |
| 1/4" to 1/2" | .004 to .010 |
| 1/2" to 1" | .007 to .015 |
| 1" and over | .015 to .025 |
SFM to spindle speed calculator
Drilling notes
Reduce feed and speed for holes deeper than about 4× drill diameter, poor chip evacuation, work hardening materials, or limited coolant. Peck cycles can help clear chips but may affect tool life depending on material and drill geometry.
FAQ
Are these chart values final production recommendations?
No. They are starting values for planning. Use the specific cutting tool manufacturer data, workholding condition, coolant method, and machine limits before running production parts.
Why do different speed and feed charts disagree?
Charts assume different tool materials, coatings, tool life targets, rigidity, coolant, radial engagement, and material hardness. A generic chart should be adjusted to the actual tool and setup.
How do I convert SFM to RPM?
For inch units, RPM = 3.82 × SFM ÷ cutter diameter in inches. For metric units, RPM = 1000 × Vc ÷ (π × diameter in millimeters).
How do I calculate drill RPM?
Use RPM = 3.8197 × SFM ÷ drill diameter in inches, or RPM = 1000 × Vc ÷ (π × diameter in millimeters).
When should drill speed be reduced?
Reduce speed for deep holes, poor coolant, work-hardening materials, hard cast iron, stainless, nickel alloys, or if chips show excessive heat.
Data sources and limits
These charts are starting values only. Actual speeds and feeds depend on tool geometry, coating, holder rigidity, coolant, chip evacuation, radial width of cut, axial depth of cut, material hardness, and machine power.
- Sandvik Coromant: milling definitions for cutting speed, spindle speed, feed per tooth, feed per minute, MRR, cutting force, and power.
- Kennametal: RPM, IPM, chip-load, and SFM formulas.
- Harvey Tool: general carbide end mill SFM and chip-load tables.
- Norseman Drill & Tool: HSS drill speed and feed rules of thumb.
- LittleMachineShop: turning, milling, drilling, and reaming cutting speed tables.