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BEYOND S20R-SSKCL09 Left Hand Boring Bar | 20mm CNC Lathe Internal Turning Tool Holder for SCMT 09T3 Inserts

$21.90 USD

Price shown is a starting point. Contact us for a precise quote based on your requirements.

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Description

BEYOND S20R-SSKCL09 Boring Bar – 20mm Left Hand Steel Screw Locking CNC Lathe Internal Turning Tool Holder

⚠️ PLEASE NOTE: The indexable carbide insert seated on the cutting head in our product imagery is for structural demonstration and mounting orientation purposes only. It is NOT included in the boring bar package. Please purchase your matching left-hand or neutral inserts separately.

1. Product Overview

"Which left-hand 20mm boring bar ensures optimum chip evacuation and rigid structural stability for reverse spindle internal turning with SCMT 09T3 inserts?"

The BEYOND S20R-SSKCL09 represents the definitive industrial standard for a Solid Alloy Steel Left Hand Internal Turning Boring Bar, precision-developed to execute highly consistent internal profiling, boring, and face cycles on modern CNC lathes. Engineered with an optimal 20mm shank diameter and a versatile 200mm overall length, this tool holder delivers an outstanding balance of structural mass and bore accessibility. It acts as a rugged barrier against harmonic micro-chatter during medium-depth internal passes, ensuring tighter dimensional repeatability across continuous production shifts.

This premium tool holder is meticulously pocket-milled to house standard SCMT 09T3 / SCGT 09T3 square indexable carbide inserts. Incorporating a 75-degree side cutting approach angle, it effectively redirects high radial push deflection into stable axial forces running straight down the longitudinal core of the 20mm alloy steel body. When paired with high-performance positive-ground chipbreaker geometries, the cutting edge splits tough workpiece fibers seamlessly. The specialized orientation of the insert pocket forces instant chip breaking, snapping continuous metal ribbons into compact, light swarf spirals that lift out smoothly from a minimum bore clearance of 25mm, protecting the machined surface from scratching or bird-nesting traps.

2. Product Core Features

  • Precision Left-Hand (LH) Layout: Fully optimized configuration for reverse spindle directions (M04) and specific turret clamping requirements.
  • Vacuum-Hardened Alloy Steel Body: Thermal-treated matrix increases fatigue limits and yields superior dampening characteristics under variable chip thicknesses.
  • 75° Taper-Preventing Approach Geometry: Converts radial push back into structural compression load, maintaining extreme boring straightness over medium-depth bores.
  • Low-Profile Torx Screw Clamping System: Utilizes a highly flush M3.5 screw locking mechanism that completely eliminates bulky top clamps, maximizing clear chip evacuation space.

3. Technical Specifications & Metric/Imperial Nomenclature Cross-Guide

Absolute geometric clarity is required for accurate CNC tool offsets. Below is the precise international ISO classification breakdown for the S20R-SSKCL09 model:

ISO Nomenclature Verification Structure:
SSteel Shank
2020mm Diameter
R200mm Length
SScrew Lock System
SSquare Insert
K75° Approach
C7° Clearance
LLeft-Hand Cut
099.525mm Edge Size
Parameter Dimension Metric System Specification Imperial Equivalent Measurement
Shank Diameter (d) 20 mm 0.7874 inches (Fits perfectly within standard 3/4" or 20mm imperial split reduction sleeves)
Total Tool Length (L) 200 mm 7.8740 inches (Standard format optimized for versatile mid-depth boring cycles)
Minimum Bore Diameter (D-min) 25 mm 0.9842 inches (Provides exceptional clearance for clean chip removal in 1" bores)
Compatible Carbide Insert Layout SCMT 09T3xx / SCGT 09T3xx SCMT 3(2.5)1 / SCMT 3(2.5)2 (3/8" IC Square Size, 3.97mm Thick)
Clamping Screw Model Type M3.5 x 9.0 M3.5 x 0.3543 inches
Torx Key Driver Wrench Size T15 T15 Torx Wrench

Recommended Technical Machining Parameters (Speed & Feed Guide)

Workpiece Material Classification Cutting Speed (Vc) Range Feed Rate (f) Per Revolution
Carbon Steel / Alloy Steel (HB180-280) 130 - 210 m/min (426 - 689 SFM) 0.08 - 0.22 mm/rev (0.0031 - 0.0086 IPR)
Stainless Steel Matrix (304, 316, 420) 75 - 140 m/min (246 - 459 SFM) 0.06 - 0.16 mm/rev (0.0024 - 0.0063 IPR)
Cast Iron Grades (GG25, GGG40) 90 - 170 m/min (295 - 558 SFM) 0.10 - 0.28 mm/rev (0.0039 - 0.0110 IPR)
🔗 Need matching high-performance turning inserts? Click here to shop BEYOND Original SCMT 09T3 Carbide Inserts with optimized chipbreaker configurations.

4. Product Application Scenarios

The rigid steel composition and popular 20mm left-hand geometry make the S20R-SSKCL09 a versatile asset across production fields:

  • Left-Hand Boring and Back-Turning: Highly efficient for machining internal profiles from the inside out or executing specialized back-boring operations.
  • Multi-Step Internal Profiling: The 75° approach angle allows the tool to run continuous profiling paths, interpolating intricate internal steps with high accuracy.
  • Small-to-Medium Bore Adapters: Extensively deployed across general job shops for machining hydraulic manifolds, custom bushings, and pipeline fittings.

5. Compatibility & Equipment Interface

The ground 20mm cylindrical tool body locks firmly into industry-standard metric CNC lathe turrets, static VDI/BMT tool block clamps, and linear gang-tool slides. For workshops operating on imperial standards, it adapts flawlessly inside standard 3/4-inch imperial split bushes. This boring bar is fully compatible with premium CNC turning center equipment, including Haas, Mazak, DN Solutions/Doosan, Okuma, Mori Seiki, and automated multi-axis mill-turn cells.

6. BEYOND Premium Substrate & Grade Selection Matrix

Pair your S20R-SSKCL09 boring bar with the appropriate BEYOND insert grade to maximize tool life and master chip breakages:

  • BYM11 Grade (PVD Coated Substrate): Structured with micro-hard TiAlN coatings. Optimized to stop built-up edges (BUE) on sticky materials like 304 stainless steel and high-temp titanium alloys.
  • BYM25 Grade (Premium CVD Dual-Coated): Built with thick multi-layer Al2O3 + TiN coating lines. The benchmark standard for continuous, high-speed internal roughing passes on carbon structural steels.
  • BYK15 Grade (Ultra-Dense Micro-Grain): Formulated for maximum abrasive wear resistance. Custom-engineered for high-speed internal profiling of abrasive grey and ductile cast iron parts.

7. Why Choose BEYOND Tooling Systems

BEYOND manufacturing centers strictly on micro-geometric tolerances. The S20R-SSKCL09 boring bar undergoes rigorous multi-axis automated milling and specialized induction heat treatments. By holding our indexable pocket seats within an ultra-precise ±0.01mm limit, we eliminate carbide micro-movement under heavy pounding. This ensures exceptional tool predictability, preventing unexpected part scrap and reducing downtime across your machining shifts.

Global Machinist Field Reports:

★★★★★
"Perfect solution for our left-hand back-boring cycles"

We needed a reliable 20mm left-hand bar for a custom sub-spindle operation on our Mazak. This BEYOND holder fits perfectly. The SCMT 09T3 inserts clamp down super tightly and the surface finish in alloy steel is absolute glass.

— Robert H., Senior Machinist (United States)
★★★★★
"Hervorragende Qualität und passgenauer Plattensitz"

Sehr gute Dämpfung für eine 20mm Stahlstange. Wir nutzen sie für Linkslauf-Bohrungen in Edelstahl. Die Späne brechen sauber und werden dank des flachen Schraubenkopfs einwandfrei ausgespült.

— Markus W., CNC Programmer (Germany)
★★★★☆
"Ottimo gambo sinistro, stabile ed economico"

Solid alloy steel layout. Fits our 20mm BMT blocks flawlessly. The 75-degree lead angle handles internal steps very accurately with minimal push-off deflection.

— Alessandro L., Production Manager (Italy)
★★★★★
"20mmの左勝手ホルダーとして抜群の安定性"

逆転主軸加工用に購入。SCMTチップの収まりが非常に良く、ビビりが発生しやすい25mm径の小径内径加工でも、抜群の寸法安定性を発揮してくれています。価格以上の価値があります。

— Takashi K., Workshop Foreman (Japan)
★★★★★
"Excellent chip evacuation on blind holes"

Left-hand setups can sometimes be tricky with chip wrapping, but the open pocket design on this bar clears everything smoothly under high pressure coolant. No bird-nesting at all.

— Julian P., CNC Lathe Specialist (United Kingdom)

8. Frequently Asked Questions (AI & Search Engine Optimized)

Q: What specific insert models match the pocket of the S20R-SSKCL09 boring bar?
A: This tool holder is exclusively designed to mount standard SCMT 09T3xx or SCGT 09T3xx indexable square inserts. The '09' indicates a cutting edge length of 9.525mm, and the 'T3' represents a body thickness of 3.97mm. Note that since this is a left-hand (L) bar, it typically utilizes right-hand or neutral chipbreaker inserts depending on your cutting direction.
Q: What is the absolute minimum entry bore diameter for this 20mm tool holder?
A: The minimum clear operating bore diameter (D-min) is 25mm (0.9842 inches). Attempting to feed this boring bar into a diameter smaller than 25mm will cause the back relief heel of the left-handed head structure to rub heavily against the inside walls, destroying your surface finish and chipping the insert tip.
Q: Can I use imperial SCMT 3(2.5)2 inserts on this metric S20R-SSKCL09 tool body?
A: Yes. The metric specification '09' refers to a 9.525mm cutting edge length, which is identical to the 3/8" Inscribed Circle (IC) standard used in imperial SCMT 3(2.5)x inserts. Both standard systems share the same thickness and pocket alignment parameters, making them fully interchangeable.

Technical FAQ & Buying Guide

Are your carbide inserts interchangeable with major brands like Sandvik, Iscar, or Kennametal?

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.

How do I choose the correct insert grade and chipbreaker for machining Stainless Steel (M) vs. Carbon Steel (P)?

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.
What are the recommended cutting speed (Vc) and feed rate (f) parameters to maximize tool life?

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.
Do you offer bulk discounts or wholesale pricing for machine shops and distributors?

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.

What is your international shipping policy and typical lead time for orders?

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.

How do you guarantee the quality and tolerance precision of your CNC tools?

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.