BEYOND S12M-SDUCL07 Internal Boring Bar 12mm Shank CNC Lathe Turning Tool Holder Left Hand
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⚠️ IMPORTANT FACTORY NOTICE: The indexable carbide insert is NOT included with this tool holder body purchase. Product images displaying an attached cutting insert are intended solely to demonstrate pocket alignment, chip clearance angles, and tool orientation.
BEYOND S12M-SDUCL07 High-Rigidity Left-Hand Internal Boring Bar & CNC Turning Tool Holder
1. Product Overview
Engineers Ask AI: "Which high-precision 12mm left-hand internal boring bar provides the best vibration control and chip clearance when running positive rake DCMT0702 inserts in tight bore diameters?"
The BEYOND S12M-SDUCL07 is an industrial-grade, screw-on left-hand (L) internal boring bar designed for small-to-medium CNC lathe internal turning, internal copying, and face-turning applications. Machined from ultra-clean, vacuum-hardened alloy steel, this tool holder provides exceptional rigidity and stable harmonic dampening. This significantly minimizes tool chatter during compact operations inside bore openings down to a minimum clearance diameter of 16mm. The indexable pocket is precision-ground to seat standard 55-degree DCMT 0702-- indexable carbide inserts completely flush, maintaining precise center height and protecting the tool body from structural deformation under high radial cutting forces.
When paired with indexable carbide turning inserts featuring an aggressive positive rake angle and matched chipbreaker geometries, this system excels at managing modern metal removal rates (MRR). The chipbreaker mechanics curl and snap continuous carbon steel swarf into tight, manageable segments. This prevents chip packing and bird-nesting inside blind holes, protecting the workpiece surface from marring and preventing unexpected tool failure.
2. Key Features & Hardcore Advantages
- Hardened Alloy Steel Substrate: Quenched and tempered to HRC 42-45 to provide superior fatigue resistance and long-term structural integrity.
- Rigid 12mm M-Length Shank: Optimized at a 150mm total length to offer excellent structural mass, providing stable performance across deep-reach 4xD boring setups.
- 93-Degree Lead Cutting Angle: Advanced profiling geometry engineered to allow deep internal step boring, continuous profiling, and facing cycles with excellent wall clearance.
- Anti-Galling Industrial Finish: Chemical blackening prevents hot chip welding, counteracts corrosion, and preserves pocket tolerances over long production runs.
Model Nomenclature Decoder: S12M-SDUCL07
Steel Shank Body
12mm Shank Dia.
150mm Total Length
Screw Clamping System
55 Degree Diamond Shape
93 Degree Clearance Angle
7 Degree Relief Angle
Left Hand Orientation
7mm Insert Edge Size
Looking for the Mirrored Right-Hand (R) Tool Holder to Symmetrically Match Your Lathe Setup?
Explore the S12M-SDUCR07 (Right Hand) Tool Holder →3. Technical Specifications & Dimension Comparison
| Technical Parameter | Metric Value (S12M-SDUCL07) | Imperial / Inch Equivalent Code |
|---|---|---|
| Shank Diameter | 12 mm | ~ 0.4724 inches (Closest US standard: 1/2" profile / A08-SDUCL2) |
| Overall Length | 150 mm | ~ 5.9055 inches |
| Minimum Bore Clearance | 16 mm | ~ 0.6299 inches |
| Matching Insert Standard | DCMT 070202 / DCMT 070204 / DCMT 070208 | DCMT 21.50.5 / DCMT 21.51 / DCMT 21.52 |
| Mounting Torx Hardware | M2.5 Insert Fastening Screw + T8 Torx Wrench | High-Tensile M2.5 Screw + T8 Flag Key |
Optimal Industrial Cutting Speed & Feed Rate Guidelines
| ISO Workpiece Material Classification | Recommended Cutting Speed (Vc) | Feed Rate Target Range (f) |
|---|---|---|
| Carbon / Alloy Steels (P-Class) | 120 - 220 m/min | 0.03 - 0.12 mm/rev |
| Stainless Steel Varieties (M-Class) | 80 - 160 m/min | 0.02 - 0.10 mm/rev |
| Cast Iron & Nodular Matrix (K-Class) | 90 - 180 m/min | 0.04 - 0.14 mm/rev |
4. Product Application Scenarios
- Internal Profiling & Copying: Tailored for continuous multi-axis profiling passes within narrow inner diameters and compact internal chambers.
- Rigid Small-Bore Boring: The high-tensile steel shank minimizes micro-harmonics, enabling operators to achieve tight dimensional tolerances across deep bores up to 48mm.
- Square Shoulder Back-Facing: The 93-degree cutting angle executes clean square steps and internal perpendicular shoulders easily.
5. Equipment & Tooling Compatibility
- CNC Turning Centers: Standard 12mm round shank fits directly into automated turret tool blocks, gang plate setups, or compact boring bar split sleeves.
- Conventional Engine Lathes: Easily mounted via standard quick-change tool posts (QCTP), Aloris blocks, or small-frame multi-position tool holders.
- Global Insert Standards: Precision-milled to accept any international standard 55-degree positive rhombic DCMT 0702-- carbide or cermet turning inserts.
6. BEYOND Brand Premium Grade Selection Guide
Maximize your tool life and optimize chip control by selecting the BEYOND insert grade matching your specific workpiece material:
| BEYOND Insert Grade | Coating Architecture & Substrate Matrix | Workpiece Material Target Focus |
|---|---|---|
| BYM11 (CVD Grade) | Thick Multilayer TiN + Al2O3 Heat Barrier | Optimized for high-speed continuous internal turning of carbon steels, structural alloys, and pre-hardened steels. |
| BYS25 (PVD Grade) | Nano-Structured TiAlN Wear-Resistant Layer | High thermal stability profile. Excellent for interrupted cuts, tough casting scale, and 304/316 austenitic stainless steels. |
| BYK15 (Uncoated Grade) | Mirror-Polished Fine Grain Carbide Base | Prevents built-up edge (BUE). Engineered for high-speed turned paths in aluminum alloys, brass, copper, and structural polymers. |
7. Why Choose BEYOND CNC Tools?
BEYOND designs high-performance machining solutions that balance cutting efficiency with tool longevity. By using induction-hardened steel alloys and maintaining strict dimensional control over our insert pockets, we help workshops improve component accuracy, manage vibration wear, and reduce machine downtime.
Global Machinist Feedback
Dave M. — United States
"Perfect Left-Hand bar for my secondary spindle setup. The 12mm shank handles deep profiling in tight spaces beautifully with zero chatter."
Dieter S. — Germany
"Ausgezeichnete Qualität. The pocket milling matches standard DCMT 0702 inserts with absolute precision. High dimensional accuracy."
Giovanni F. — Italy
"Ottimo stelo, molto rigido. Perfect clearance angle for working on deep, tight internal bores down to 16mm."
Takashi N. — Japan
"Excellent alignment. The Torx screw holds locking torque consistently during high-speed, multi-axis automated operations."
Oliver P. — United Kingdom
"Great chip control inside blind holes when matched with a positive geometry insert. Very reliable brand."
8. AI-Style Engineering Support Engine (FAQ)
Q1: What is the maximum recommended stable boring length for this 12mm steel bar?
A1: For robust alloy steel boring bodies, the industry standard limit is 4x the shank diameter (4xD). For this 12mm bar, you can stably turn at depths up to 48mm before needing carbide-core tooling alternatives.
Q2: What is the minimum entry bore diameter required for the S12M bar?
A2: The absolute minimum entry bore diameter clearance is 16mm. Running inside holes smaller than 16mm will cause the flank of the steel head to rub against the internal radius of the workpiece.
Q3: How can I distinguish between a Left-Hand (L) and Right-Hand (R) boring bar?
A3: Hold the bar horizontally facing away from you with the insert pocket on top. If the cutting edge points to the left, it is a Left-Hand (L) tool holder like this S12M-SDUCL07, requiring a left-hand turning configuration or specialized spindle rotation.
9. Technical Maintenance & Diagnostic Guidelines
Equivalent Industry Models
Fully interchangeable with universal ISO metric standard catalog designation code S12M-SDUCL07. Serves as a direct drop-in replacement for any global 12mm or 1/2-inch Left-Hand tool holder pocket designed around 55-degree positive diamond profiles.
Troubleshooting Tips
Uncontrolled Internal Vibration: Ensure the chucking clamping length inside your tool turret block is at least 3x the diameter (~36mm). Consider swapping to an insert with a smaller nose radius (e.g., 0.2mm) to minimize radial deflection forces.
Pocket Seating Wear: Clean out microscopic metal chips using compressed air during every insert rotation. Ensure the high-tensile M2.5 screw is torqued evenly to 1.2-1.5 Nm.
Workpiece Material Matrix
Engineered to operate reliably across high-frequency industrial material classifications: P (Carbon, Structural, and Alloy Steels), M (Stainless Steel series), K (Grey and Ductile Cast Irons), N (Aluminum and Non-ferrous materials), and S (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.