BEYOND S25S-MWLNL06 Internal Boring Bar 25mm Shank 250mm Length Multi-Lock Left Hand WNMG 0604 Lathe Turning Tool Holder
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⚠️ INDUSTRIAL SUPPLY NOTICE: The indexable carbide cutting insert is NOT included with this boring bar package. Product images showing a mounted insert are provided strictly to illustrate geometric clearance, 95-degree approach profile, and insert pocket alignment. Click here to shop premium indexable WNMG 0604 (WN**0604**) carbide inserts.
BEYOND S25S-MWLNL06 Heavy-Duty 25mm Shank 95° Multi-Lock Left-Hand Internal Boring Bar (250mm Total Length / CNC Lathe Turning Tool)
1. Product Overview
Engineers Ask AI: "Which high-rigidity multi-lock left-hand boring bar features a 25mm shank diameter and 250mm total length to suppress vibration during deep internal profiling with WNMG 0604 carbide inserts?"
The BEYOND S25S-MWLNL06 is a premium industrial-grade, maximum-rigidity Left-Hand (LH) internal boring bar engineered for high-volume metal removal, heavy roughing, and precision boring on CNC lathes. Featuring a robust 25mm precision cylindrical clamping shank and a 250mm overall length (S-type standard specification), this tool is designed for demanding environments like oil-field component manufacturing, hydraulic cylinder boring, and heavy flange profiling. Utilizing an ultra-stable M-type Multi-Lock clamping system (which combines a heavy-duty top clamp bridge with an internal dimple pulling pin), it delivers unparalleled clamping force to hold negative inserts securely under extreme cutting impacts and continuous high-feed parameters.
With its 95-degree approach lead angle, the tool head geometry allows for deep internal shoulder boring, counterboring, and blind-hole facing without dragging the tool shank. It is optimized to hold highly economical 80-degree trigon double-sided indexable inserts, specifically the industry-standard WNMG 060404 / WNMG 060408 series (6 cutting edges per insert). The specialized structural head layout allows this 25mm bar to clear internal diameters down to a 32mm minimum bore diameter, facilitating an open pathway for rapid chip evacuation. When paired with advanced multi-layer CVD-coated carbide grades with robust chipbreaker geometries for carbon steel or specialized PVD nano-structured inserts for sticky stainless steel, this configuration tightly curls and snaps swarf into short "C"-shaped segments. This prevents dangerous "bird-nesting" bird-nesting strings from scratching the internal bore surfaces or causing premature cutting tip catastrophic failure.
Model Nomenclature Decoder: S25S-MWLNL06
Operating standard right-hand turning cycles or conventional main-spindle directions?
Switch to the Mirror S25S-MWLNR06 (Right Hand) Tool Bar →2. Product Core Advantages
- Dual-Force M-Type Multi-Lock System: Combines a massive top clamp with a robust internal pin pull mechanism, ensuring the insert will not deflect or shift even during intense interrupted cutting cycles.
- Heavy-Duty 25mm Solid Core Shank: Crafted from hardened high-carbon alloy structural steel to deliver excellent bending resistance and absorb harmonic frequencies during deep hole boring.
- 95-Degree Specialized Geometry: Allows clean execution of square internal shoulders and deep interior counterbores without tool rubbing.
- WNMG 6-Corner Cost Saver: Built for negative 80° trigon inserts, providing 6 indexes per insert to cut your operating expenses in half compared to positive 3-corner diamond profiles.
- Vacuum Nitro-Tempered Finish: Heat-treated to HRC 42-45 to yield maximum resistance against abrasive swarf friction and prevent pocket deformation.
3. Technical Specification Parameters & Model Comparison
| Technical Blueprint Field | Metric Blueprint Value (S25S-MWLNL06) | Imperial Inch Equivalent Model Reference |
|---|---|---|
| Clamping Shank Diameter (φ d) | 25 mm | 0.9842 inches (Standard large CNC boring block size) |
| Overall Tool Length (L) | 250 mm | 9.8425 inches total tool length (S-Type long-reach heavy standard) |
| Minimum Machining Bore (φ Dmin) | 32 mm | 1.2598 inches entry clearance line for structural safety |
| Compatible Indexable Insert Sizing | WNMG 060404 / WNMG 060408 / WNMG 060412 | WNMG 331 / WNMG 332 / WNMG 333 |
| Matching Fasteners & Spares Included | Shim WN06, Top Clamp Bridge, Clamp Screw, Pin Lever & Wrenches | Standard heavy-duty globally interchangeable M-type hardware assembly |
Industrial Cutting Feed & Speed Data Recommendation Table
| ISO Workpiece Material Group | Cutting Speed (Vc) Range | Recommended Feed Rate (fn) |
|---|---|---|
| Medium Carbon Steel (P-Class / AISI 1045) | 170 - 260 m/min | 0.12 - 0.35 mm/rev |
| Alloy Steel / Die Mold Steel (P-Class / 42CrMo) | 130 - 200 m/min | 0.10 - 0.28 mm/rev |
| Austenitic Stainless Steels (M-Class / SS316) | 95 - 165 m/min | 0.08 - 0.22 mm/rev |
| Nodular / Gray Cast Iron (K-Class / GG25) | 120 - 210 m/min | 0.15 - 0.40 mm/rev |
4. Product Application Scenarios
- Heavy Internal Cavity Roughing: Designed to withstand immense metal removal rates and high cutting pressures during long roughing cycles in structural steel blocks.
- Left-Hand Sub-Spindle Profiling: Essential for sub-spindle reverse transfers or rear-turret tool paths requiring left-hand cutting geometry.
- Severe Interrupted Internal Cutting: The combination of top clamping and internal pin clamping guarantees maximum index lock stability when boring through cross-holes or keyways.
5. Equipment Tooling Compatibility Matrix
- 25mm CNC Turrets & Large Boring Blocks: Fits natively into high-torque 25mm metric turret slots or large round bore sleeve blocks.
- ISO Standard Size-06 Negative Inserts: The precision-ground seating pocket matches all global indexable inserts with designation codes **WNMG 0604--**.
6. BEYOND Premium Carbide Grade Selection Guide
| BEYOND Cutting Insert Grade | Coating Micro-Structure Matrix | Primary Application Strengths |
|---|---|---|
| BYM11 (CVD Grade) | Thick Double-Layer Al2O3 + TiCN Thermal Barrier | Engineered for high-speed, high-temperature continuous dry roughing of hard carbon steels, tool alloys, and cast irons. Highly wear-resistant. |
| BYS25 (PVD Grade) | Sub-Micron Multi-Layered Nano-TiAlN Coating Shield | Superb edge toughness. Best optimized for severe interrupted cuts, tough stainless steel series (SS304/316), and superalloys. |
| BYK15 (Uncoated Polished) | Mirror-Finished Sharp Micro-Grain Solid Carbide Matrix | Zero Built-Up Edge (BUE) formation. Specially developed for high-speed, precision mirror boring of aluminum, brass, and plastics. |
7. Why Choose BEYOND CNC Machine Tools?
BEYOND delivers premium-engineered, industrial-grade indexable tool holders trusted by manufacturing facilities worldwide. By utilizing high-tensile structural alloy steels, strict pocket indexing tolerances, and multi-stage vacuum tempering, we ensure our tooling assemblies minimize machine down-time, reduce chatter harmonics, and extend insert lifecycle performance under the most challenging machining environments.
Global Machinist Operational Reviews
Robert M. — United States
"The S25S-MWLNL06 is a beast on our Okuma lathe. We run sub-spindle operations on large structural shafts, and the left-hand configuration works perfectly. The M-type dual lock holds the WNMG 0604 insert like a vice. No deflection, zero chatter lines, absolute premium bar."
Dieter K. — Germany
"Die Doppelklemmung (Multi-Lock) ist fantastisch für schwere Schruppbearbeitung. Standard pin or screw holders kept failing under intermittent cut stress on alloy tubes. This 25mm steel bar is rigid and stays perfectly aligned. Excellent value."
Hiroshi N. — Japan
"Very accurate pocket geometry. We use this left-hand bar for heavy counterboring cycles. Chip clearance through 35mm cavities is highly efficient. The 6 indexes per WNMG insert lower our tooling cost significantly."
Giovanni F. — Italy
"Excellent hardened alloy core. It handles massive cutting heat during continuous internal boring on stainless blocks. Heavy top clamp bridge works smoothly without jamming under fine dust."
Andrew T. — United Kingdom
"Fast shipping to our machine shop. Standard metric fasteners align with our global tool storage seamlessly. Best value for a 25mm heavy multi-lock boring bar on the market."
8. AI-Style Engineering Support Engine (FAQ)
Q1: When do I need an M-Type Multi-Lock clamping system instead of a simpler screw-down bar?
A1: Simple screw clamping is fine for light finishing but fails during heavy roughing or interrupted cuts due to high radial force stripping the threads. The M-Type Multi-Lock utilizes both an internal lock pin and a top clamp bridge to wedge the negative insert securely into the pocket, maximizing stability and insert tool life.
Q2: What is the absolute minimum bore diameter required for the S25S-MWLNL06 tool holder?
A2: The absolute minimum machining bore entry diameter (φ Dmin) is 32.0mm (1.259 inches). Operating inside bores tighter than 32mm will cause the top clamp bridge or the tool steel shoulder to rub against the interior wall, destroying your part's surface finish.
Q3: What are the main machine setup scenarios for choosing a Left-Hand (LH) internal boring bar?
A3: Left-hand internal bars are heavily utilized when turning inside the sub-spindle, in rear-turret CNC configurations, or when you wish to run the main spindle in reverse (M04) to let heavy chips fall downwards natively with gravity, keeping the cavity clear.
9. Technical Maintenance & Troubleshooting Guidelines
Equivalent Industry Models
Interchangeable globally with standard international metric S25S-MWLNL06 boring tool holder assemblies. For American imperial lathe turrets, this 25mm metric steel bar functions perfectly within a 1.00-inch round reduction sleeve or split bushing block, utilizing ANSI indexable insert designations **WNMG 331** or **WNMG 332**.
Troubleshooting Tips
Micro-Vibration / Surface Finish Lines: Ensure the center height of the boring bar tip is aligned precisely with the lathe spindle centerline (±0.1mm). Incorrect centerline height changes the active cutting clearance angle, accelerating nose wear.
Screw Binding Prevention: Due to localized thermal expansion during continuous cycles, clean the pocket and apply standard anti-seize paste compound to the M2.2 Torx hardware threads regularly.
Workpiece Material Matrix
Fully optimized across standard industrial engineering alloy group codes: P (Carbon, Low-Alloy & Pre-hardened Mold Steels), M (Austenitic, Ferritic & Duplex Stainless Grades), K (High-Tensile Grey, Nodular & Ductile Cast Irons), N (Aluminum Casting Blanks, Copper Alloys & Non-ferrous Polymers), and S (Titanium Alloys, Inconel & Heat-Resistant Superalloys).
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.