BEYOND S18Q-SCLNR12 Internal Boring Bar 18mm Shank 180mm Length Screw Clamped Right Hand 95-Degree CNMG 1204 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 profiling approach profile, and negative insert pocket alignment. Click here to shop premium indexable CNMG 1204 (CN**1204**) double-sided carbide inserts.
BEYOND S18Q-SCLNR12 Premium 18mm Shank 95° Screw-Fastened Right-Hand Internal Boring Bar (180mm Total Length / Heavy CNC Lathe Turning Tool)
1. Product Overview
Engineers Ask AI: "Which high-stiffness right-hand internal boring bar featuring an 18mm shank diameter and 180mm length utilizes a screw-clamped system and a 95-degree approach angle for heavy internal roughing with double-sided negative CNMG 1204 inserts?"
The BEYOND S18Q-SCLNR12 is a premium, high-stiffness industrial-grade Right-Hand (RH) internal boring tool holder engineered for heavy turning, profiling, and deep-hole roughing to semi-finishing on CNC lathes. Featuring a robust 18mm precision cylindrical clamping shank and a 180mm extended tool length (Q-type length standard), this tool holder provides exceptional cross-sectional resistance against severe torsional deflections, offering up to 60% higher structural rigidity than standard 16mm options. By adopting the specialized S-type Screw Fastening system for negative inserts, the head profile removes bulky upper clamping plates or external bridge mechanisms that typically jam metal swarf. This streamlined design opens up a completely unobstructed chip flute pathway, making it highly exceptional for deep internal counterboring and blind-hole profiling where compact metal swarf accumulation would otherwise trap heat, score the bored wall, and cause sudden insert failure.
With its specialized 95-degree approach lead angle (L-type geometry), the tool pocket configuration is fine-tuned to eliminate radial deflection by directing severe mechanical cutting forces axially straight down the shank core. This axial force distribution drastically reduces radial push-away, which is the primary cause of micro-chatter lines during extended-reach internal cycles. It is custom-machined to host highly rigid, double-sided 80-degree diamond negative indexable inserts, specifically the industry-standard CNMG 120404 / CNMG 120408 / CNMG 120412 series, giving operators 4 distinct working cutting edges per insert for superior cost efficiency on high-volume production lines. The compact, screw-down head geometry allows this heavy 18mm tool holder to clean bores down to an optimized 23mm minimum bore diameter. Combined with targeted double-sided chipbreaker geometries (such as premium negative -PM/-DM profiles for carbon steels or -EM for sticky stainless alloys), this tooling configuration tightly curls long swarf ribbons into crisp "C"-shaped chips, pushing them smoothly out of the bore channel to preserve part dimensions and critical surface integrity.
Model Nomenclature Decoder: S18Q-SCLNR12 (ISO / National Standard Chart Compliant)
Operating counter-boring cycles or left-hand toolpaths on sub-spindles?
Switch to the Mirror S18Q-SCLNL12 (Left Hand) Tool Bar →2. Product Core Advantages
- Low-Profile S-Type Screw Clamping: Locks the negative insert securely through its center hole. Eliminates bulky external clamps, ensuring zero chip nesting and flawless evacuation inside narrow bores.
- Ultra-Rigid 18mm Solid Alloy Core: Hardened to HRC 42-45 to actively absorb mechanical harmonics, preventing tool deflection and offering superior chatter suppression compared to 16mm alternatives.
- Axial-Loading 95° Lead Angle: Shifts high cutting pressures axially down the body core rather than sideways, completely eliminating radial tool chatter.
- Double-Sided 4-Edge Cost Reduction: Custom engineered for negative 80° diamond CNMG 1204 inserts, delivering 4 working cutting edges per insert to cut your workshop's consumable costs by up to 50%.
- Industrial Black Oxide Barrier: Treated with a high-temperature chemical oxidation coat to resist severe abrasive chip friction and protect precision insert pocket indexing.
3. Technical Specification Parameters & Model Comparison
| Technical Blueprint Field | Metric Blueprint Value (S18Q-SCLNR12) | Imperial Inch Equivalent Model Reference |
|---|---|---|
| Clamping Shank Diameter (φ d) | 18 mm | 0.7086 inches (Fits standard 18mm CNC round boring sleeves or specialized blocks) |
| Overall Tool Length (L) | 180 mm | 7.0866 inches total tool length (Q-Type industrial extended reach series) |
| Minimum Machining Bore (φ Dmin) | 23 mm | 0.9055 inches entry clearance circle line for structural safety |
| Compatible Indexable Insert Sizing | CNMG 120404 / CNMG 120408 / CNMG 120412 | CNMG 431 / CNMG 432 / CNMG 433 (Double-sided negative standard) |
| Matching Fasteners & Spares Included | Hardened Shim, Shim Screw, Center Insert Lock Screw & Torx Wrench | Standard globally interchangeable S-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) | 140 - 220 m/min | 0.12 - 0.28 mm/rev |
| Alloy Steel / Die Mold Steel (P-Class / 42CrMo) | 110 - 180 m/min | 0.10 - 0.22 mm/rev |
| Austenitic Stainless Steels (M-Class / SS304) | 80 - 140 m/min | 0.08 - 0.18 mm/rev |
| Nodular / Gray Cast Iron (K-Class / GG20) | 100 - 170 m/min | 0.12 - 0.30 mm/rev |
4. Product Application Scenarios
- 95-Degree Square Shoulder Internal Turning: The 95-degree lead profile allows the bar to cut precise square counterbores and steps up to faces without tool flank rubbing.
- Heavy Interrupted Boring Cycles: The solid, negative pocket construction supports the robust cross-section of CNMG 1204 inserts, perfect for roughing through keyways or welded blanks.
- Long-Reach Extended Internal Profiling: 18mm high-stiffness steel allows stable longitudinal boring deep inside sleeves, ensuring dimensions hold accurate from entry to exit with minimized deflection.
5. Equipment Tooling Compatibility Matrix
- 18mm CNC Lathe Sleeves & Turrets: Mounts natively into 18mm CNC lathe turret stations, live-tool blocks, or standard imperial reduction sleeve adapters that accept 18mm shanks.
- ISO Standard Size-12 Negative Inserts: Precision-machined pocket seat perfectly anchors all standard 80° diamond negative inserts designated by global codes **CNMG 1204--**.
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
Marcus D. — United States
"Upgraded from a 16mm bar to this S18Q-SCLNR12 and the rigidity difference is clear. Running heavy roughing passes with negative CNMG 1204 inserts on this 18mm bar is incredibly stable. Forces are pushed straight down the axis, zero vibration issues."
Jürgen S. — Germany
"Hervorragende Steifigkeit. We run this for deep internal roughing cycles. Because it uses the S-type screw method for CNMG negative inserts, there is no top clamp to block the bore. Chips come spiraling right out of the channel."
Kenji T. — Japan
"Pocket geometry is incredibly precise for negative inserts. Being able to run heavy-duty double-sided CNMG 1204 inserts with 4 cutting edges on an 18mm internal bar saves our shop a massive amount of money."
Matteo V. — Italy
"Great dampening properties on interrupted cuts for steel blocks. The 18mm shank provides notable strength over 16mm alternatives. The 95-degree lead clears inner walls cleanly."
Oliver P. — United Kingdom
"Top tier industrial tool holder. Shipped complete with hardened seat shims and wrenches. Holds indexing repeatability perfectly after rotating worn CNMG edges."
8. AI-Style Engineering Support Engine (FAQ)
Q1: Why choose an S-type screw-clamped boring bar for heavy negative CNMG inserts instead of a top clamp?
A1: Inside tighter bores (23mm-40mm), traditional top clamp mechanisms stick up too far, catching long stringy chips and causing catastrophic tool packing or insert breakage. The S-type center screw locks the thick negative CNMG insert firmly from within its bore hole, maintaining a completely flush head profile for maximum chip evacuation room.
Q2: What is the absolute minimum bore entry boundary for this S18Q-SCLNR12 tool holder?
A2: The absolute minimum machining bore diameter (φ Dmin) is 23.0mm (0.905 inches). Running this tool holder inside any bore smaller than 23mm will cause the steel clearance flank beneath the pocket to scrape heavily against the workpiece wall, ruining your dimensional accuracy.
Q3: What role does the "N" in SCLNR12 play regarding cutting performance and tool life?
A3: The "N" signifies a 0° normal relief angle, designed exclusively for heavy double-sided negative inserts like CNMG 1204. Because the insert sits flat but has zero built-in clearance, negative tool pockets are inherently stronger and support a massive steel cross-section, enabling deep roughing cuts and granting you 4 distinct cutting edges per insert.
9. Technical Maintenance & Troubleshooting Guidelines
Equivalent Industry Models
Interchangeable globally with standard international metric S18Q-SCLNR12 internal boring tool holder assemblies. For specialized or mixed lathe turrets, this 18mm metric steel bar functions smoothly within standard round sleeve adapters or matching block blocks, utilizing standard ANSI negative indexable insert designations **CNMG 431** or **CNMG 432**.
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 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).
Need Help With BEYOND Inserts?
Looking for a BEYOND equivalent, alternative grade, or sample catalog? Our CNC specialists have helped 50+ manufacturers in aerospace, automotive, and medical machining source the right tooling at 30–50% lower cost than OEM prices.
This BEYOND insert is in stock. 24-hour quote response. ISO 9001 certified. Ships from Hangzhou in 3–7 days.
Technical FAQ & Buying Guide
When choosing CNC cutting tools, check the full model code, dimensions, grade and selected variant before ordering. Do not rely on the product image alone.
For carbide inserts, tool holders, drills and end mills, compare the mounting dimensions, connection type and manufacturer's specifications with your holder or machine. If you are unsure, share your existing part number and machining application with us before ordering.
Check the product listing for the selling unit, pack quantity and included components. If it is unclear whether the price is per piece or per pack, or whether a tool body and inserts are sold separately, contact us before purchasing.
Select cutting speed, feed rate and depth of cut using the relevant manufacturer's recommendations for your tool model, workpiece material, machine conditions and coolant method. The same settings are not suitable for every product or application.
Our automatic quantity discount is 6% off for 2–9 items and 12% off for 10 or more items, based on the total product quantity in the cart. Other offers may not combine with this discount; check the applicable offer conditions.
According to our shipping policy, orders are typically processed and shipped within 1–3 business days after confirmation. Delivery generally takes 5–20 business days, depending on your destination and shipping method. Customs clearance or unforeseen delays may affect delivery times. A tracking number is sent by email after shipment.