Designed for heavy-duty steel machining, our HRC58 round nose end mill delivers outstanding edge strength and tool rigidity. This industrial round nose end mill features a negative rake angle to prevent chipping during aggressive CNC milling. As a durable 4-flute round nose milling cutter, it provides superior surface finish and extended service life in hardened steels.
Supplied by Durable Mills, this high-performance round nose end mill is developed for high-efficiency profiling, 3D contouring, and slot milling across mold steels and hardened metals up to HRC58. Formulated with ultra-fine 0.8 μm tungsten carbide and 10% Cobalt, it combines high thermal durability with structural toughness for stable industrial machining.
| Cobalt Content (Co) | 10% |
| Grain Size | 0.8 μm (Micrograin Carbide) |
| Hardness Rating | HRA 91.5 – 92 |
| Target Workpiece Hardness | Up to HRC58 |
| Flute Number | 4 Flutes (4T) |
| ISO Category | Workpiece Material | Axial Cut (ap) | Radial Cut (ae) | Cutting Speed Vc (m/min) | Feed per Tooth fz (mm/z) |
|---|---|---|---|---|---|
| P | Carbon Steel / Alloy Steel (<35 HRC) | ap ≤ 1.5D | ae ≤ 0.15D | 180 | 0.0085D |
| P | Alloy Steel (35–48 HRC) | ap ≤ 1.5D | ae ≤ 0.15D | 140 | 0.0075D |
| M | Stainless Steels | ap ≤ 1.5D | ae ≤ 0.10D | 100 | 0.006D |
| K | Gray Cast Iron / Ductile Iron (<32 HRC) | ap ≤ 1.5D | ae ≤ 0.15D | 150 | 0.007D |
| H | Hardened Steel (45–58 HRC) | ap ≤ 1.0D | ae ≤ 0.08D | 90 | 0.005D |
| Model Type | Cutting Dia. (D mm) | Flute Length (Lc mm) | Shank Dia. (d mm) | Overall Length (L mm) | Radius (R mm) | Flutes |
|---|---|---|---|---|---|---|
| DM-3*8*3*50*4T | 3.0 | 8 | 3 | 50 | 0.5 / 1.0 | 4 |
| DM-3*12*3*75L*4T | 3.0 | 12 | 3 | 75 | 0.5 / 1.0 | 4 |
| DM-3*15*3*100*4T | 3.0 | 15 | 3 | 100 | 0.5 / 1.0 | 4 |
| DM-1*3*4*50*4T | 1.0 | 3 | 4 | 50 | 0.2 | 4 |
| DM-1.5*4*4*50*4T | 1.5 | 4 | 4 | 50 | 0.2 | 4 |
| DM-2*5*4*50*4T | 2.0 | 5 | 4 | 50 | 0.2 / 0.5 | 4 |
| DM-3*8*4*50*4T | 3.0 | 8 | 4 | 50 | 0.2 / 0.5 / 1.0 | 4 |
| DM-4*10*4*50*4T | 4.0 | 10 | 4 | 50 | 0.2 / 0.5 / 1.0 | 4 |
| DM-4*16*4*75*4T | 4.0 | 16 | 4 | 75 | 0.5 / 1.0 | 4 |
| DM-4*20*4*100*4T | 4.0 | 20 | 4 | 100 | 0.5 / 1.0 | 4 |
| DM-5*13*5*50*4T | 5.0 | 13 | 5 | 50 | 0.5 / 1.0 | 4 |
| DM-5*20*5*75*4T | 5.0 | 20 | 5 | 75 | 0.5 / 1.0 | 4 |
| DM-5*25*5*100*4T | 5.0 | 25 | 5 | 100 | 0.5 / 1.0 | 4 |
| DM-6*15*6*50*4T | 6.0 | 15 | 6 | 50 | 0.2 / 0.5 / 1.0 | 4 |
| DM-6*13*6*50*4T | 6.0 | 13 | 6 | 50 | 0.5 / 1.0 | 4 |
| DM-6*25*6*75*4T | 6.0 | 25 | 6 | 75 | 0.5 / 1.0 | 4 |
| DM-6*30*6*100*4T | 6.0 | 30 | 6 | 100 | 0.5 / 1.0 | 4 |
| DM-6*40*6*150*4T | 6.0 | 40 | 6 | 150 | 0.5 / 1.0 | 4 |
| DM-8*20*8*60*4T | 8.0 | 20 | 8 | 60 | 0.2 / 0.5 / 1 / 2 / 3 | 4 |
| DM-8*28*8*75*4T | 8.0 | 28 | 8 | 75 | 0.5 / 1 / 2 / 3 | 4 |
| DM-8*35*8*100*4T | 8.0 | 35 | 8 | 100 | 0.5 / 1 / 2 / 3 | 4 |
| DM-8*50*8*150*4T | 8.0 | 50 | 8 | 150 | 0.5 / 1 / 2 / 3 | 4 |
| DM-10*25*10*75*4T | 10.0 | 25 | 10 | 75 | 0.2 / 0.5 / 1 / 1.5 / 2 / 3 | 4 |
| DM-10*40*10*100*4T | 10.0 | 40 | 10 | 100 | 0.5 / 1 / 2 / 3 | 4 |
| DM-10*50*10*150*4T | 10.0 | 50 | 10 | 150 | 0.5 / 1 / 2 / 3 | 4 |
| DM-12*30*12*75*4T | 12.0 | 30 | 12 | 75 | 0.2 / 0.5 / 1 / 1.5 / 2 / 3 | 4 |
| DM-12*45*12*100*4T | 12.0 | 45 | 12 | 100 | 0.5 / 1 / 2 / 3 | 4 |
| DM-12*60*12*150*4T | 12.0 | 60 | 12 | 150 | 0.5 / 1 / 2 / 3 | 4 |
A round nose end mill (bull nose end mill) provides a rounded corner radius that distributes mechanical and thermal loads away from the edge corners. This significantly reduces chipping risk and yields higher feed capabilities in tough steels compared to sharp 90-degree square cutters.
The negative rake angle reinforces the cutting edge volume, offering strong impact absorption during interrupted cutting and abrasive machining of steel up to HRC58.
Yes. Durable Mills delivers custom engineering services, including non-standard corner radiuses (R), extended reach options, and specialized PVD coatings for global tool distributors and machine shops.
Please visit our Contact Page or email our technical sales department at info@durablemills.com. We respond to all wholesale inquiries within 24 hours.
