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GM Series Carbide Corner Radius End Mill 4 Flutes

Designed for radius shoulder milling and profile machining with flat bottoms in steels up to 38HRC. Solid carbide substrate, 35° helix, TiSiN nano coating.

Solid Carbide 4 Flutes 35° Helix TiSiN Coated R0.2-R3.0 ≤38HRC
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GM Series Carbide Corner Radius End Mill 4 Flutes
GM Series Carbide Corner Radius End Mill 4 Flutes
4 flute side cutting edge
TiSiN coating surface

Procurement & Commercial Terms

MOQ1 pc (sample/stock) | 50 pcs (OEM/bulk)
Lead Time3–5 days (standard stock) | 10–15 days (custom/OEM)
InventoryD3.0-D12.0 in stock. D16.0 available on short notice.
Custom OptionsExtended cutting length (GM-4RL), custom radius sizes (R0.1-R5.0), AlTiN/TiAlN/uncoated, laser marking
PackagingIndividual vacuum blister + anti-rust paper | Rigid export cartons (50/100 pcs)
ShippingDHL/FedEx/UPS for samples | Air/Sea freight for bulk. Incoterms: EXW, FOB, CIF, DDP

GM-4R Dimensions (Standard & Long)

GM-4R Dimensions (Standard & Long)

ModelD (mm)R (mm)H(mm)d (mm)L (mm)TypeStock
GM-4R-1.0-0.2-3-4-501.00.23450Standard●
GM-4R-1.5-0.2-4.5-4-501.50.24.5450Standard●
GM-4R-1.5-0.3-4.5-4-501.50.34.5450Standard●
GM-4R-2.0-0.2-6-4-502.00.26450Standard●
GM-4R-2.0-0.3-6-4-502.00.36450Standard●
GM-4R-2.5-0.2-7.5-4-502.50.27.5450Standard●
GM-4R-2.5-0.5-7.5-4-502.50.57.5450Standard●
GM-4R-3.0-0.2-9-4-503.00.29450Standard●
GM-4R-3.0-0.5-9-4-503.00.59450Standard●
GM-4R-3.0-0.5-9-3-503.00.59350Standard●
GM-4R-3.0-0.5-12-3-753.00.512375Long○
GM-4R-3.0-0.5-15-3-1003.00.5153100Long○
ModelD (mm)R (mm)H(mm)d (mm)L (mm)TypeStock
GM-4R-4.0-0.2-10-4-504.00.210450Standard●
GM-4R-4.0-0.3-10-4-504.00.310450Standard●
GM-4R-4.0-0.5-10-4-504.00.510450Standard●
GM-4R-4.0-0.5-14-4-754.00.514475Long○
GM-4R-4.0-0.5-15-4-1004.00.5154100Long○
GM-4R-5.0-0.5-13-5-505.00.513550Standard●
GM-4R-5.0-0.5-13-5-755.00.513575Long○
GM-4R-5.0-0.5-18-5-1005.00.5185100Long○
GM-4R-5.0-1.0-13-6-505.01.013650Standard●
GM-4R-6.0-0.2-20-6-756.00.220675Long○
GM-4R-6.0-0.2-25-6-1006.00.2256100Long○
GM-4R-6.0-0.5-16-6-506.00.516650Standard●
GM-4R-6.0-0.5-20-6-756.00.520675Long○
GM-4R-6.0-0.5-25-6-1006.00.5256100Long○
GM-4R-6.0-1.0-16-6-506.01.016650Standard●
GM-4R-6.0-1.0-20-6-756.01.020675Long○
GM-4R-6.0-1.5-20-6-756.01.520675Long○
ModelD (mm)R (mm)H(mm)d (mm)H (mm)L (mm)TypeStock
GM-4R-8.0-0.2-20-8-608.00.22082060Standard●
GM-4R-8.0-0.2-25-8-758.00.22582575Long○
GM-4R-8.0-0.2-30-8-1008.00.230830100Long○
GM-4R-8.0-0.5-20-8-608.00.52082060Standard●
GM-4R-8.0-0.5-25-8-758.00.52582575Long○
GM-4R-8.0-0.5-30-8-1008.00.530830100Long○
GM-4R-8.0-0.5-45-8-1508.00.545845150Long○
GM-4R-8.0-1.0-20-8-608.01.02082060Standard●
GM-4R-8.0-1.0-25-8-758.01.02582575Long○
GM-4R-8.0-1.0-30-8-1008.01.030830100Long○
GM-4R-8.0-1.0-45-8-1508.01.045845150Long○
GM-4R-8.0-1.5-20-8-608.01.52082060Standard●
GM-4R-10.0-0.2-25-10-7510.00.225102575Long○
GM-4R-10.0-0.2-30-10-10010.00.2301030100Long○
GM-4R-10.0-0.5-25-10-7510.00.525102575Long○
GM-4R-10.0-0.5-30-10-10010.00.5301030100Long○
GM-4R-10.0-0.5-50-10-15010.00.5501050150Long○
GM-4R-10.0-1.0-25-10-7510.01.025102575Long○
GM-4R-10.0-1.0-30-10-10010.01.0301030100Long○
GM-4R-10.0-1.0-50-10-15010.01.0501050150Long○
GM-4R-10.0-1.5-25-10-7510.01.525102575Long○
GM-4R-10.0-2.0-25-10-7510.02.025102575Long○
GM-4R-10.0-2.0-30-10-10010.02.0301030100Long○
GM-4R-10.0-3.0-25-10-7510.03.025102575Long○
GM-4R-10.0-3.0-30-10-10010.03.0301030100Long○
ModelD (mm)R (mm)H(mm)d (mm)L (mm)TypeStock
GM-4R-12.0-0.2-30-12-7512.00.2301275Long○
GM-4R-12.0-0.2-35-12-10012.00.23512100Long○
GM-4R-12.0-0.5-30-12-7512.00.5301275Long○
GM-4R-12.0-0.5-35-12-10012.00.53512100Long○
GM-4R-12.0-0.5-55-12-15012.00.55512150Long○
GM-4R-12.0-1.0-30-12-7512.01.0301275Long○
GM-4R-12.0-1.0-35-12-10012.01.03512100Long○
GM-4R-12.0-1.0-55-12-15012.01.05512150Long○
GM-4R-12.0-1.5-30-12-7512.01.5301275Long○
GM-4R-12.0-2.0-30-12-7512.02.0301275Long○
GM-4R-12.0-2.0-35-12-10012.02.03512100Long○
GM-4R-12.0-3.0-30-12-7512.03.0301275Long○
GM-4R-16.0-0.5-40-16-10016.00.54016100Long○
GM-4R-16.0-0.5-40-16-15016.00.54016150Long○
GM-4R-16.0-0.5-75-16-15016.00.57516150Long○
GM-4R-16.0-1.0-40-16-10016.01.04016100Long○
GM-4R-16.0-1.0-75-16-15016.01.07516150Long○
GM-4R-16.0-2.0-45-16-10016.02.04516100Long○
GM-4R-16.0-3.0-45-16-10016.03.04516100Long○
GM-4R-20.0-0.5-45-20-10020.00.54520100Long○
GM-4R-20.0-0.5-75-20-15020.00.57520150Long○
GM-4R-20.0-1.0-45-20-10020.01.04520100Long○
GM-4R-20.0-1.0-75-20-15020.01.07520150Long○

● In stock            ○ Make-to-order                          Tolerance: D≤12 → 0~-0.020mm | D>12 → 0~-0.030mm.              CAD/STEP files available on request.            

CAM Setup & Machining Guidance for Steel

Side Milling vs Radius Shoulder Parameters

  • ✅ Side Milling (Down): ae = 0.5D–1.0D (roughing) | ae = 0.05D–0.1D (finishing)

  • ✅ Radius Shoulder: ap = 1.5D, ae = 0.1D for smooth radius blending

  • ✅ Profile Milling: Use step-down ap = 0.3D per pass for stable engagement

  • ✅ Use climb milling to minimize tool deflection & improve surface finish

Machine & Setup Requirements

  • ⚠️ Use high-precision collets/chucks. Runout must be <0.005mm

  • ⚠️ Minimize overhang to reduce vibration, especially at D3.0-D5.0

  • ⚠️ Air blow or mist cooling recommended for TiSiN thermal stability

  • ⚠️ For low-rigidity setups, reduce Vf by 20–30% and use conservative ae

Material Compatibility & Hardness Limits

WorkpieceHardnessSuitabilityNotes
P20 / 718H / NAK55≤38 HRC◎ ExcellentOptimized for mold plate radius shoulders & profile milling
Carbon/Alloy Steel (42CrMo, 4140)≤38 HRC◎ ExcellentStable for structural component radius profiling
Cast Iron / Ductile Iron-◎ ExcellentAir blow cooling recommended; TiSiN resists abrasive wear

◎ = Very Suitable | ○ = Suitable | GM-4R is optimized for ≤38HRC. For 40–55HRC hardened steels, use our HMX series.

Typical Applications in CNC Manufacturing

🔩 Mold Base Radius Shoulders

Radius shoulder profiling on P20/NAK55 mold plates. Eliminates sharp 90° corners that cause stress concentration and cracking.

🚗 Automotive Component Profiling

Profile milling of gear housings, brackets & transmission cases with radius corners for improved fatigue resistance.

🏭 Jigs & Fixtures Radius Slots

Radius corner slot milling for jigs, fixtures & tooling. Reduces stress concentration and improves part longevity.

Factory Production & Quality Control

5 axis CNC grinding and optical inspection for corner radius end mills

Manufacturing Process & QA Steps

  • 🔹 Substrate: Ultra-fine carbide grade (0.4μm grain size) for high toughness & edge stability

  • 🔹 Grinding: 5-axis CNC machines maintain 35° helix ±0.5° & radius accuracy ±0.01mm

  • 🔹 Coating: PVD TiSiN layer (2.5–3.5μm) applied at <450°C to preserve edge sharpness & prevent substrate softening

  • 🔹 Inspection: 100% laser diameter measurement, radius profile verification, runout <0.005mm test

  • 🔹 Traceability: Each batch includes laser-etched SKU, grinding date, and QC certificate. Available upon request.

📄 Download ISO 9001 & QC Reports

Frequently Asked Questions

Standard D3.0–D12.0 sizes are stocked. MOQ starts at 1 pc for samples. Bulk/OEM orders (50+ pcs) ship in 10–15 days. Custom radius sizes or coatings require 15–20 days.

Yes. We offer GM-4RL long-cutting-edge variants. Custom radius sizes (R0.1-R5.0), extended lengths, and coatings (TiAlN, AlTiN, uncoated) are available. Laser branding & private packaging supported for distributors.

Corner radius end mills have rounded corners (R0.2-R3.0) with a flat bottom, ideal for radius shoulders and profile milling. Flat end mills have sharp 90° corners. Radius corners reduce stress concentration and improve tool life.

For ≤38HRC, use ae = 0.1D for radius shoulder profiling with ap = 1.5D. For general side milling, use ae = 0.5D–1.0D for roughing and ae = 0.05D–0.1D for finishing. Always use climb milling.

Request Quote for GM Series Carbide Corner Radius End Mill 4 Flutes

Specify your diameter range, material, and monthly volume. We respond with pricing, stock status within 24 hours.

ISO 9001 Certified Factory
Export Packaging Standard
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