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ProductsHRC55 Solid Carbide Bull Nose End Mill 4 Flute for Steel Machining
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Corner Radius End MillsIn-StockPremiumRecommended

HRC55 Solid Carbide Bull Nose End Mill 4 Flute for Steel Machining

High-performance HRC55 solid carbide bull nose end mills (4 flute) for steel machining. Excellent wear resistance & corner protection. Factory direct pricing, large stock available. Get a free sample today!

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Product Overview

Welcome to our premium line of HRC55 Solid Carbide Bull Nose End Mills (4 Flute). As a professional tungsten steel CNC tool manufacturer, we engineer these corner radius end mills specifically for high-efficiency and high-precision machining of pre-hardened and hardened steels up to HRC55.

Product Function

The bull nose (corner radius) design combines the advantages of both square end mills and ball nose end mills. It is primarily used for:
  • Profile Milling & Cavity Machining: Ideal for mold and die making.
  • Face Milling & Bottom Machining: Provides an excellent surface finish.
  • Corner Protection: The radius edge significantly reduces tool chipping and edge wear during heavy-duty cutting, effectively extending the tool life when machining hard steel materials.

Product Features

  • Premium Micro-Grain Carbide: Made from high-quality tungsten steel matrix, ensuring exceptional hardness, rigidity, and wear resistance.
  • Advanced Nano-Coating: Specially formulated coating for high-temperature resistance and superior oxidation resistance, perfect for dry and high-speed cutting.
  • 4-Flute Geometry: Optimizes chip evacuation and increases core strength, providing vibration-free machining and smooth surface finishes.
  • Precision Corner Radius: Strictly controlled radius tolerance (R0.05 to R3.0 available) to meet accurate 3D profiling requirements.

Specifications (In-Stock)

We maintain a massive inventory of standard sizes. Custom sizes and OEM orders are also welcome.
D1 (Cutter Dia.)
L2 (Length of Cut)
D2 (Shank Dia.)
L1 (Over All Length)
Radius
φ1.0
3
4
50
R0.05
φ1.5
4.5
4
50
R0.05
φ2.0
6
4
50
R0.05
φ1.0
3
4
50
R0.1
φ1.2
3.6
4
50
R0.1
φ1.5
4.5
4
50
R0.1
φ2.0
6
4
50
R0.1
φ2.5
7.5
4
50
R0.1
φ3.0
9
4
50
R0.1
φ4.0
10
4
50
R0.1
φ5.0
15
6
50
R0.1
φ6.0
15
6
50
R0.1
φ8.0
20
8
60
R0.1
φ10.0
25
10
75
R0.1
φ12.0
30
12
75
R0.1
φ1.0 ~ φ12.0
3 ~ 30
4 ~ 12
50 ~ 75
R0.2
φ4.0 ~ φ10.0
16 ~ 35
4 ~ 10
75 ~ 100
R0.2 (Long Series)
φ1.0 ~ φ12.0
3 ~ 30
4 ~ 12
50 ~ 75
R0.3
φ4.0 ~ φ8.0
16 ~ 35
4 ~ 8
100
R0.3 (Long Series)
φ4.0 ~ φ8.0
10 ~ 20
4 ~ 8
50 ~ 60
R0.4
φ1.5 ~ φ12.0
4.5 ~ 30
4 ~ 12
50 ~ 75
R0.5
φ3.0 ~ φ12.0
9 ~ 35
3 ~ 12
75 ~ 100
R0.5 (Long Series)
φ3.0 ~ φ12.0
9 ~ 30
3 ~ 12
50 ~ 75
R1.0
φ3.0 ~ φ12.0
9 ~ 30
4 ~ 12
75 ~ 100
R1.0 (Long Series)
φ4.0 ~ φ10.0
10 ~ 30
4 ~ 10
50 ~ 75
R1.5
φ6.0 ~ φ12.0
15 ~ 30
6 ~ 12
50 ~ 100
R2.0
φ10.0 ~ φ12.0
30
10 ~ 12
75
R3.0
(Note: For the complete and detailed size list, please refer to our catalog or contact sales. The table above highlights our standard stock range.)

RPM / Feed Reference Table (For HRC55 Steel)

The following parameters are for reference only. Please adjust according to your machine rigidity, tool overhang, and cooling method.
Cutter Dia. (D1)
Spindle Speed (RPM)
Feed Rate (mm/min)
Ap (Max Depth)
Ae (Max Width)
φ2.0
10,000 - 12,000
400 - 600
0.05D
0.5D
φ3.0
8,000 - 10,000
500 - 700
0.05D
0.5D
φ4.0
6,500 - 8,500
600 - 800
0.05D
0.5D
φ6.0
4,500 - 6,000
600 - 900
0.05D
0.5D
φ8.0
3,500 - 4,500
600 - 900
0.05D
0.5D
φ10.0
2,800 - 3,500
500 - 800
0.05D
0.5D
φ12.0
2,300 - 2,800
500 - 800
0.05D
0.5D

Promotion Policy

We value long-term partnerships. Take advantage of our exclusive offers:
  1. Free Sample: Free samples can be provided to test our quality, if clients agree to pay for the shipping cost.
  1. First Order Coupon: New clients can enjoy a **USD
    50discountcoupon∗∗forthefirstorder,ifthetotalorderamountismorethanUSD50 discount coupon** for the first order, if the total order amount is more than USD
    
    500.
  1. Big Order Discount: Clients can enjoy a 2% ~ 5% discount, if the total order amount is more than USD $5,000.

Clients Benefits

Why choose us as your CNC tool supplier?
  • Factory-Direct Pricing: Cut out the middleman. Maximize your profit margins with our competitive manufacturer prices.
  • Guaranteed Consistency: Strict QC processes (using advanced Zoller inspection machines) ensure every batch performs exactly like the last.
  • Massive Ready Stock: As shown in our specifications, we stock a huge variety of sizes for fast dispatch, reducing your downtime.
  • OEM & Customization: We provide laser marking, custom packaging, and can manufacture non-standard cutters tailored to your specific drawings.

FAQ

Q1: Can this end mill process materials other than HRC55 steel? A: Yes. While optimized for hardened steel up to HRC55, it also performs excellently on pre-hardened steel, carbon steel, alloy steel, and cast iron.
Q2: Does the corner radius (bull nose) really make a difference? A: Absolutely. The radius strengthens the cutting edge, distributing cutting forces and heat more evenly. This prevents the corners from chipping, which is the most common failure mode in square end mills when cutting hard metals.
Q3: How fast can you ship my order? A: For standard sizes listed in our specifications, we usually dispatch within 24-48 hours. For custom or bulk orders, lead time is typically 5-10 working days.
Q4: How do I claim my free sample? A: Simply click "Contact Us" or send an inquiry with your required specifications and delivery address. Our sales team will arrange the sample shipment immediately upon confirming the shipping cost with you.