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Products4 Flute Inner R Angle Milling Cutter, Uncoated Carbide Concave Radius End Mill for CNC Machining
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4 Flute Inner R Angle Milling Cutter, Uncoated Carbide Concave Radius End Mill for CNC Machining

High-precision 4 flute inner R angle milling cutter made of premium tungsten steel. Uncoated design for superior performance in non-ferrous metals and general engineering. Available in R0.2 to R5.0. Factory direct price, free samples available. Enhance your CNC machining precision today!

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4 Flute Inner R Angle Milling Cutter - Uncoated Carbide

Product Function

Specifically designed for machining precise internal radii (concave corners) and rounding edges on workpieces. This tool is essential for mold making, aerospace components, and medical parts where smooth, accurate inner R-profiles are required to reduce stress concentration or meet design aesthetics.

Product Features

  • Premium Material: Manufactured from high-grade micro-grain tungsten steel (Carbide) for exceptional hardness and wear resistance.
  • 4-Flute Design: Provides better rigidity and surface finish compared to 2-flute versions, ensuring stable cutting at higher feed rates.
  • Uncoated Sharpness: The uncoated edge remains extremely sharp, preventing material build-up (BUE), making it ideal for aluminum, copper, and plastics.
  • High Precision: Strict tolerance control on the R-angle and head diameter to ensure perfect consistency in batch production.
  • Large Chip Space: Optimized flute geometry for efficient chip evacuation, preventing tool breakage.

Specifications

Based on our standard inventory, the specifications are as follows (Unit: mm):
Inner R Angle
Head Dia. D
Shank Dia. d
Overall Length L
R0.2 - R1.75
3.6 - 0.5
4
50
R1.5 - R2.5
3.0 - 1.0
6
50
R2.25 - R3.5
3.5 - 1.0
8
50
R3.75 - R4.0
2.5 - 2.0
10
60
R4.5 - R5.0
3.0 - 2.0
12
60
(Note: For detailed Head Dia. matching specific R-angles, please refer to the technical chart or contact our sales team.)

RPM/Feed Reference Table

Note: The following data is for reference. Adjust based on your machine's rigidity and workpiece material.
Workpiece Material
Cutting Speed (VC)
Feed per Tooth (fz)
Aluminum Alloy
180-300 m/min
0.02 - 0.08 mm/t
Copper/Brass
120-200 m/min
0.02 - 0.06 mm/t
Plastic/Nylon
200-400 m/min
0.05 - 0.10 mm/t
General Steel (<HRC30)
80-120 m/min
0.01 - 0.04 mm/t

Promotion Policy

  1. Free Sample: Free samples can be provided if clients agree to pay for the shipping cost.
  1. First Order Coupon: New clients can enjoy a USD 50 discount coupon for the first order (minimum order amount > USD 500).
  1. Big Order Discount: Clients can enjoy a 2%~5% discount if the total order amount exceeds USD 5,000.

Client Benefits

  • Cost Efficiency: Factory-direct sales eliminate middlemen, providing you with high-performance tools at competitive prices.
  • Consistent Quality: Every batch undergoes rigorous QC to ensure the R-angle precision meets your blueprints.
  • Fast Shipping: Large stock available for all standard sizes listed above, ensuring 24-48 hour dispatch.
  • Technical Support: Our engineers can help optimize your cutting parameters to extend tool life.

FAQ

Q: Can this tool be used on Stainless Steel?

A: While primarily designed for non-ferrous and general steel, it can work on soft stainless steel. For hardened stainless steel, we recommend our AlTiN coated series.
Q: Do you offer custom R-angles?

A: Yes, as a manufacturer, we provide OEM/ODM services for non-standard radii and shank diameters.
Q: Why choose 4 flutes over 2 flutes for inner R machining?

A: 4 flutes offer better tool life and a much smoother surface finish due to the increased core strength and more frequent cutting contact.

For more high-performance cutting solutions, please explore our full range of Carbide End Mills for CNC Machining, or contact our expert sales team for a custom quote.