4-Flute · nACo · R1.5mm · HRC65 · Standard Reach
8mm 4-Flute R1.5mm nACo Solid Carbide Corner Radius End Millfor HRC65 Hardened Steel
nACo (nano-AlCrN composite) corner radius end mills deliver the highest performance tier for hard milling in die steel, tool steel, and hardened components up to HRC65. The corner radius geometry is especially critical at high hardness — it eliminates the notching failure mode that destroys sharp-corner tools in hardened steel. Combined with nACo's 3,800 HV hardness and 1,100°C oxidation resistance, this tool enables dry semi-finish and finish passes in H13, P20, D2, and S7 mould steel directly after heat treatment.
Get Pricing & Stock
Reference price
$34.28
Ref. factory price (USD)
Based on rod stock cost as of 2026-03-31. Final quotation may differ.

8mm 4F R1.5mm nACo
L2 20mm · D2 8mm · OAL 60mm
Standard Reach · HRC65
✓ Factory direct pricing
✓ MOQ 1 piece, ships 1–5 days
✓ Custom radius in 0.1mm increments
Full Dimensions
Technical Specifications
| Corner Radius | 1.5 mm |
| Cutter Diameter (D1 h7) | 8 mm |
| Flute Length (L2) | 20 mm |
| Shank Diameter (D2 h6) | 8 mm |
| Overall Length (L1) | 60 mm |
| Number of Flutes | 4 |
| End Geometry | Corner Radius (Bull Nose) |
| Coating | nACo Nano-AlCrN composite |
| Max Material Hardness | HRC65 |
| Reach Category | Standard (L1/D1 = 7.5×) |
| Helix Angle | 30°–35° |
| 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 · R1.5mm

R1.5mm Corner Geometry
Large fillet for structural and automotive components requiring R1.5 corners
- ▸Single-pass production of R1.5mm fillet features
- ▸Eliminates interpolation entry required for ball-nose on same radius
- ▸Lower vibration tendency vs ball nose on shallow 3D surfaces
- ▸Preferred for automotive and aerospace structural pocket corners
ø8mm Applications
8mm nACo — Where This Tool Fits
- ▸Automotive component shoulder milling
- ▸Pump body and valve pocket features
- ▸Gearbox cover profiling
- ▸Large mould runner channel machining
Coating Performance
nACo on Corner Radius Geometry
- ▸nACo hardness > 3,800 HV — critical for corner edge stability in HRC65 steel
- ▸Oxidation to 1,100°C — supports dry cutting in deep die pockets
- ▸Corner radius + nACo eliminates notching failure common in hard milling
- ▸Enables direct finish after heat treatment — skip grinding on mould steel
Same Diameter & Radius, Different Reach
ø8mm R1.5mm nACo · 4 Flute · HRC65 — Other Flute Lengths
Same ø8mm Diameter, Other Radii
nACo · 4 Flute · HRC65 — Other Corner Radii at ø8mm
Same Dimensions, Other Coatings
ø8mm R1.5mm / L2 20mm — Other Variants
Order 8mm R1.5mm 4-Flute nACo Today
Factory direct. MOQ 1 piece. Pricing confirmed within 4 hours.

