Korloy MGMN400-M NC3120 4mm Double-Ended Universal Steel Grooving Insert (10pcs)
Price shown is a starting point. Contact us for a precise quote based on your requirements.
The Original Korloy MGMN400-M NC3120 is a high-performance 4.0mm Double-Ended Grooving Insert engineered for Universal Steel Machining. Featuring the advanced NC3120 CVD grade, this insert is the ultimate "workhorse" for medium-to-heavy grooving tasks. It is specifically designed for workshops that need a single, reliable grade to handle a variety of steel alloys, providing a stable tool life even when moving from continuous cuts to interrupted surfaces.
Stability for Medium-Duty Cuts: At 4.0mm width, the MGMN400 provides excellent lateral rigidity. Combined with the NC3120 grade, it effectively resists thermal cracking and micro-chipping, making it far more forgiving than harder, wear-only grades.
Technical Specifications:
| Brand | Korloy (100% Genuine) |
| ISO Code | MGMN400-M |
| Insert Width (w) | 4.0 mm |
| Grade | NC3120 (Universal Steel Grade - CVD) |
| Chipbreaker | -M (Stable Medium-Cutting Geometry) |
Core Performance Benefits:
- Multi-Steel Capability: Highly effective in carbon steels, alloy steels, and pre-hardened steels.
- CVD Wear Protection: The thick multi-layer coating ensures a long tool life at higher cutting speeds compared to PVD grades.
- 4.0mm High Rigidness: Reduced tool deflection in deep radial grooving, ensuring straighter parting faces.
- Superior Chip Breaking: The -M geometry curls chips efficiently, preventing surface scratches and improving operator safety.
Recommended Cutting Parameters:
| Material Group | Cutting Speed (Vc) | Feed Rate (f) |
|---|---|---|
| Medium Carbon Steel (1045) | 110 - 220 m/min | 0.10 - 0.25 mm/rev |
| Alloy Steel (4140/SCM440) | 90 - 180 m/min | 0.08 - 0.20 mm/rev |
| Mild Steel (A3/1020) | 130 - 250 m/min | 0.12 - 0.30 mm/rev |
Compatible Tool Holders:
Pairs perfectly with heavy-duty 4.0mm MGEHR/L tool bars:
- External Holders: MGEHR 2020-4 / 2525-4 / 3232-4
Finding Your 4mm Sweet Spot: NC3120 vs. NC3020/NC3030
For 4.0mm grooving, the choice between grades depends on your machine's stability:
The Universal Balance. Your first choice for 90% of steel applications. It’s tough enough for light interruptions and hard enough for high speed.
The Wear Expert. Best for perfectly stable, continuous CNC production where max tool life is the only goal.
The Tough Guardian. Use this if you have heavy interruptions, scale, or vibrations that chip the other grades.
Machinist's Pro Tip: In 4.0mm grooving, chips carry significant heat. If you see the NC3120 edge wearing too fast, increase your coolant pressure. If the chips aren't breaking, slightly increase the feed rate ($f$) to engage the -M chipbreaker properly.
Packaging: 10 pieces per box.
Korloy MGMN400-M NC3120 price, 4.0mm steel grooving insert for CNC, MGMN400-M cutting speed and feed, universal grooving insert for 4140 steel, best 4mm parting tool for carbon steel
Technical FAQ & Buying Guide
Absolutely. Our CNC carbide inserts (including CNMG, WNMG, DNMG, and APMT series) are manufactured strictly adhering to international ISO/ANSI specifications. A CNMG 120408 from OYYU BEYOND will flawlessly fit any standard turning tool holder or indexable tool from major global brands like Sandvik Coromant, Kennametal, Iscar, Walter, or SECO, providing a highly cost-effective premium alternative without sacrificing tolerance or tool life.
We offer optimized CVD and PVD multi-layer coatings for different ISO material groups:
- For Carbon/Alloy Steel (ISO P): Choose our thick multi-layer CVD coated grades (e.g., Al2O3 + TiN). They provide exceptional crater wear resistance and thermal barriers during high-speed dry or wet roughing.
- For Stainless Steel (ISO M): Choose our nano-structured PVD coated grades with sharp, positive chipbreakers (like -TM or -MA). This combination prevents work hardening and effectively controls sticky chips.
The optimal cutting parameters vary depending on the workpiece hardness and operation type:
- For General Steel Turnings: Recommended cutting speed ($V_c$) ranges from 150 to 280 m/min, with a feed rate ($f$) of 0.15 to 0.45 mm/rev.
- For Stainless Steel Finishing: Recommended cutting speed ($V_c$) is 120 to 200 m/min, with a feed rate ($f$) of 0.10 to 0.25 mm/rev.Always adjust parameters based on early wear patterns: increase $V_c$ if built-up edge occurs, or reduce $V_c$ if severe flank wear is observed.
Yes, we support machine shops, distributors, and global buyers with tiered wholesale pricing and competitive volume discounts. We also provide OEM custom manufacturing solutions for tool holders and carbide inserts based on your technical drawings. Contact our team to request a quick B2B quotation.
We provide secure worldwide express shipping (via DHL, FedEx, and UPS) with specialized, vibration-proof industrial packaging to ensure tools arrive in perfect condition. In-stock items are dispatched within 24-48 hours, while custom or bulk orders typically have a stable lead time of 15-25 days.
All our cutting tools and tool holders are manufactured strictly in accordance with ISO 9001 and international industrial standards. Every batch undergoes 100% rigorous quality control testing using high-precision optical measuring equipment to ensure reliable tool life and stable performance in continuous mass production.