CNC grinding: end mills, drills & special cutters
See how we use a CNC grinder to make carbide end mills, drills and special cutters.
Watch on YouTube4-Flute · nACo · HRC65 · Standard Reach
16mm 4-Flute nACo Solid Carbide Square End Millfor HRC65 Hardened Steel
nACo (nano-AlCrN composite) coating represents the highest-performance tier in the square end mill range. With a coating hardness exceeding 3,800 HV and an oxidation temperature of 1,100°C, nACo enables dry cutting in hardened steel up to HRC65 — direct competition with CBN tooling at a fraction of the cost. 4-flute geometry with tight tolerance on corner radius (< 0.01mm) delivers consistent surface quality in die and mould hardened cavities, hardened shaft features, and precision gear blanks. Requires rigid fixturing and maximum 0.005mm spindle runout.
D1 16mmL2 70mmD2 16mmOAL 150mm4 FlutesnACo CoatingHRC65Standard ReachMOQ 1 pc
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Reference price
$291.61
Ref. factory price (USD)
Based on rod stock cost as of 2026-05-06. Final quotation may differ.
16mm 4F nACo Square EM
L2 70mm · D2 16mm · OAL 150mm
Standard Reach · HRC65
✓ Factory direct pricing
✓ MOQ 1 piece, ships 1–5 days
✓ Custom OAL and helix available
Full Dimensions
Technical Specifications
| Cutter Diameter (D1 h7) | 16 mm |
| Flute Length (L2) | 70 mm |
| Shank Diameter (D2 h6) | 16 mm |
| Overall Length (L1) | 150 mm |
| Number of Flutes | 4 |
| Coating | nACo Nano-AlCrN composite |
| Max Material Hardness | HRC65 |
| Reach Category | Standard (D2/L1 = 0.107) |
| Helix Angle | 30°–45° (application dependent) |
| End Geometry | Square (flat end) |
| Substrate | K10/K20 Ultra-Fine Grain Carbide |
| Shank Tolerance | h6 |
| MOQ | 1 piece |
| Lead Time (standard) | 1–5 business days |
| Lead Time (custom) | 5–15 business days |
nACo · 4 Flute · HRC65
D1 h7
16mm
L2
70mm
D2 h6
16mm
L1
150mm
Flutes
4
Reach
Standard
Where This Tool Excels
16mm nACo 4F — Recommended Applications
- ▸Large mould and die cavity machining
- ▸Structural component pocketing
- ▸Gearbox and transmission case features
- ▸Wind turbine component contouring
Machining Tip: ø16mm produces significant cutting forces. Ensure workholding clamping force is adequate. In HRC65 steel, reduce axial DOC to 0.5×D for first passes to verify fixturing stability before committing to full depth.
Coating Performance
nACo — Why It Works
- ▸Coating hardness > 3,800 HV — harder than TiN or TiAlN
- ▸Oxidation resistance to 1,100°C — enables dry cutting in hardened steel
- ▸Direct competitor to CBN at lower tooling cost
- ▸Ideal for die/mould cavities and hardened shaft features
ISO HISO PISO MnACo end mill HRC654 flute hardened steel end millcarbide end mill hard millingHRC65 square end mill die mould
Same Diameter, Different Reach
ø16mm nACo · 4 Flute · HRC65 — Other Flute Lengths
Same Size, Different Coating
ø16mm / L2 70mm — Other Variants
Order 16mm 4-Flute nACo Today
Factory direct. MOQ 1 piece. Pricing confirmed within 4 hours.
FROM OUR WORKSHOP
Watch us grind and inspect our tools
Two videos filmed in our workshop: CNC tool grinding and dimensional inspection.
Measuring carbide end mills at 0.001 mm
Watch our ZOLLER inspection process for precision carbide end mills.
Watch on YouTube