Surface Speed Chart
This surface speed chart and surface footage chart lists SFM starting values for milling, drilling, and turning. Surface speed is the speed at the cutting edge relative to the workpiece.
Surface footage chart
| Material | Process | Recommended SFM | Source table |
|---|---|---|---|
| Free machining carbon steel | Milling | 115-140 | LittleMachineShop HSS milling chart |
| Plain carbon steel, low carbon | Milling | 65-110 | LittleMachineShop HSS milling chart |
| Austenitic stainless steel 201/304/316 | Milling | 70-75 | LittleMachineShop HSS milling chart |
| Cast iron class 20-40 | Milling | 70-100 | LittleMachineShop HSS milling chart |
| Brass C360/C377 family | Milling | 100-200 | LittleMachineShop HSS milling chart |
| Bronze C226/C651/C655/C675 | Milling | 30-80 | LittleMachineShop HSS milling chart |
| Wrought aluminum 6061/5000/6000/7000 | Milling | 165 | LittleMachineShop HSS milling chart |
| Free machining carbon steel | Drilling | 100-125 | LittleMachineShop drilling chart |
| Plain carbon steel | Drilling | 25-100 | LittleMachineShop drilling chart |
| Austenitic stainless steel | Drilling | 50-55 | LittleMachineShop drilling chart |
| Wrought or cast aluminum | Drilling | 350-400 | LittleMachineShop drilling chart |
SFM to spindle speed calculator
How surface speed affects machining
Higher surface speed increases heat and can improve productivity when the tool, coating, coolant, and machine are suited for it. Lower speed is safer for interrupted cuts, hard material, uncertain tool data, or poor rigidity.
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).
Is surface speed the same for milling and turning?
The concept is the same, but the diameter used changes. Milling uses cutter diameter; turning usually uses the workpiece diameter being cut.
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.