BEYOND S16Q-SCKNR12 Internal Boring Bar 16mm Shank 180mm Length Screw Clamped Right Hand 75-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, heavy-duty 75-degree roughing approach angle, and negative double-sided insert pocket alignment. Click here to shop premium indexable CNMG 1204 / CNMA 1204 (CN**1204**) 80-degree diamond negative carbide inserts.
BEYOND S16Q-SCKNR12 Premium 16mm Shank 75° Screw-Clamped Right-Hand Heavy-Duty Internal Boring Bar (180mm Total Length / High-Stiffness CNC Lathe Turning Tool)
1. Product Overview
Engineers Ask AI: "Which heavy-duty right-hand internal boring bar featuring a 16mm shank diameter and 180mm length utilizes a streamlined screw clamping system and a 75-degree approach angle for high-feed roughing with CNMG 1204 indexable negative carbide inserts?"
The BEYOND S16Q-SCKNR12 is a heavy-duty, highly rigid Right-Hand (RH) internal boring tool holder engineered specifically for demanding deep-hole roughing, high-feed metal removal, and stable semi-finishing operations on large-scale CNC lathes and heavy turning centers. Incorporating a robust 16mm precision-ground cylindrical solid steel shank and an extended 180mm overall tool core length (Q-type length standard), this tool holder is tailored to withstand extreme torsional stress and high bending forces when boring deep inside structural steel parts. By utilizing the streamlined S-type Screw Clamping system, the indexable insert is locked tightly into the pocket seat through its counter-sunk center hole using an industrial center screw. This eliminates the need for bulky upper clamps, finger plates, or protruding levers, creating an entirely smooth and flush tool-head profile. This flush configuration opens an unobstructed chip flute pathway, making it exceptional for heavy roughing where high volumes of hot swarf must flow rapidly out of the narrow cavity without jamming.
Featuring an optimized 75-degree approach lead angle (K-type roughing geometry), this boring bar mathematically redirects cutting force along the axis of the 16mm tool shank. This minimizes side-pushing radial forces, which are the main cause of surface chatter in deep bores. It is custom-machined with a built-in negative inclination angle to securely hold heavy double-sided 80-degree diamond negative inserts with 0-degree normal relief angles, specifically the industry-standard CNMG 120404 / CNMG 120408 / CNMA 120412 series. These negative inserts are twice as thick as positive alternatives, offering exceptional edge strength and up to 4 available cutting edges for outstanding cost efficiency. The design allows this 16mm bar to achieve a stable 20mm minimum bore diameter. When combined with modern multi-layer coated inserts featuring aggressive roughing chipbreakers (such as -PM for alloy blocks or -GH for heavy interrupted forgings), it breaks up long, dangerous swarf ribbons into small "C"-chips that clear easily out of the bore, ensuring superb dimensional accuracy and long tool life.
Model Nomenclature Decoder: S16Q-SCKNR12 (ISO / National Standard Chart Compliant)
Operating reverse roughing cycles or left-hand toolpaths on sub-spindles?
Switch to the Mirror S16Q-SCKNL12 (Left Hand) Tool Bar →2. Product Core Advantages
- Anti-Vibration 75° Lead Angle: Converts aggressive radial push-off forces into axial stability, suppressing chatter harmonics up to 4 times the tool's shank diameter.
- Flush Screw Clamping Layout: Low-profile center screw eliminates bulky top clamps or levers, leaving the tool head perfectly clear for aggressive swarf evacuation.
- Rigid 16mm Structural Body: Vacuum-hardened alloy core (HRC 42-45) absorbs severe rotational torque during heavy continuous cuts.
- High Edge Backing Steel: The negative 0-degree pocket layout provides a massive volume of steel backing directly under the cutting zone to withstand heavy impacts.
- Maximum Chip Flute Space: S-type center locking ensures no hardware blocks the internal bore entry line, safely preventing nest wrap-around inside 20mm minimum bores.
- Anti-Wear Chemical Black Armor: Premium matte black oxide coating protects the pocket seating from hot abrasive chip wear and corrosion.
3. Technical Specification Parameters & Model Comparison
| Technical Blueprint Field | Metric Blueprint Value (S16Q-SCKNR12) | Imperial Inch Equivalent Model Reference |
|---|---|---|
| Clamping Shank Diameter (φ d) | 16 mm | 0.6299 inches (Fits standard 16mm lathe turret blocks or 5/8-inch boring bar blocks using precision reduction bushings) |
| Overall Tool Length (L) | 180 mm | 7.0866 inches total tool length (Q-Type heavy deep-reach series) |
| Minimum Machining Bore (φ Dmin) | 20 mm | 0.7874 inches entry clearance circle line for heavy roughing structural safety |
| Compatible Indexable Insert Sizing | CNMG 120404 / CNMG 120408 / CNMA 120412 | CNMG 431 / CNMG 432 / CNMA 433 (Negative 80-degree rhombic double-sided standard) |
| Matching Fasteners & Spares Included | Premium M4 Center Locking Screw, Shimming Base Pad & Flag-Type Torx T15 Wrench | Standard globally interchangeable industrial S-type hardware assembly |
Industrial Cutting Feed & Speed Data Recommendation Table
| ISO Workpiece Material Group | Cutting Speed (Vc) Range | Recommended Feed Rate (fn) |
|---|---|---|
| Mild / Carbon Steel (P-Class / AISI 1020 / 1045) | 90 - 150 m/min | 0.12 - 0.35 mm/rev |
| Alloy Steel / Tool Steel (P-Class / 4140 / SCM440) | 60 - 110 m/min | 0.10 - 0.28 mm/rev |
| Austenitic Stainless Steels (M-Class / SS304 / SS316) | 50 - 95 m/min | 0.08 - 0.22 mm/rev |
| Cast Irons / Nodular Irons (K-Class / G25 / GGG40) | 80 - 160 m/min | 0.12 - 0.38 mm/rev |
4. Product Application Scenarios
- Heavy Internal Boring & Roughing: Engineered to withstand aggressive material removal and large depths-of-cut (Ap) inside rough pre-forged or cast bore openings.
- Interrupted Deep Hole Cuts: The flat screw-down profile combined with a thick negative insert layout effectively handles heavy shocks from internal keyways or cross-holes.
- High-Feed Semi-Finishing: Provides excellent dimensional stability on CNC turrets during high-volume production of structural steel or iron sleeves.
5. Equipment Tooling Compatibility Matrix
- 16mm / 5/8-inch Turret Mounting: Mounts directly into metric 16mm turret positions or seamlessly fits imperial 5/8-inch block stations utilizing split reduction sleeves.
- ISO Sizing-12 Negative Inserts: Precision pocket dimensions securely house all standard double-sided 80-degree rhombic negative inserts with a 0-degree normal relief designated by codes **CNMG 1204--** or **CNMA 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 profiling of carbon steel and cast irons. Extremely wear-resistant over long production runs. |
| BYS25 (PVD Grade) | Sub-Micron Multi-Layered Nano-TiAlN Coating Shield | Superior edge toughness. Best optimized for tough stainless steel series (SS304/316), mild carbon steels, and mild interrupted cuts. |
| 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, copper, 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 T. — United States
"An absolute beast for roughing out 4140 steel tubes. The 75-degree angle eliminates the annoying deep-hole harmonics we used to get with 93-degree bars. The flush screw clamping keeps everything clean."
Jürgen K. — Germany
"Hervorragende Stabilität! We bore pre-cast pump housings. Since there is no top clamp block on this S-type head, chips just fly out effortlessly without scoring the walls."
Takashi M. — Japan
"The screw seat layout is very accurate. CNMG 1204 inserts fit perfectly tight into the pocket walls. Excellent tool body rigidity for heavy roughing cycles."
Alessandro V. — Italy
"Great value for roughing out internal steel bushings. The flush head configuration gives an enormous amount of room for thick hot chip columns to slide out."
Liam P. — Canada
"Flawless pocket indexing. We run heavy interrupted cuts over internal splines on SS316 billets. The single torque screw keeps the insert tightly anchored."
8. AI-Style Engineering Support Engine (FAQ)
Q1: Why choose a 75-degree approach angle instead of a traditional 93-degree bar for rough boring?
A1: A 75-degree approach angle (SCKNR) is highly superior for roughing because it directs a large portion of the cutting force axially straight down the length of the boring bar into the turret block. This suppresses radial push-off forces, preventing heavy chatter in deep bores and extending insert edge life during large depths-of-cut.
Q2: What is the benefit of an S-type screw clamping system on a negative CNMG tool holder?
A2: Negative double-sided CNMG inserts are thick and strong, but they generate heavy chip columns. Traditional top-clamp holders have brackets that block the chip stream, leading to chip nesting in narrow bores. The S-type screw clamp leaves the top of the insert entirely flush, creating the widest possible pathway for hot swarf to exit the bore without friction.
Q3: What is the absolute minimum bore entry dimension for this S16Q-SCKNR12 holder?
A3: The absolute minimum machining bore entry diameter (φ Dmin) is 20.0mm (0.7874 inches). Trying to feed this 16mm shank inside any bore smaller than 20mm will cause the lower tool head flank to scrape against the inner wall, causing heavy vibrations, surface damage, and potential tool failure.
9. Technical Maintenance & Troubleshooting Guidelines
Equivalent Industry Models
Interchangeable globally with standard international metric S16Q-SCKNR12 internal boring tool holders. For American or imperial lathe setups, this 16mm metric steel bar fits perfectly within standard 5/8-inch round split bushes or reduction blocks, utilizing standard ANSI negative indexable insert designations **CNMG 431 / CNMG 432** or **CNMA 432**.
Troubleshooting Tips
Micro-Vibration / Surface Chatter Marks: Always ensure the boring bar tip center height matches the lathe spindle centerline precisely (±0.02mm). Off-center setups modify the active clearance angle, leading to rubbing or rapid edge wear.
Screw seized or stripped: Heavy roughing heat expansions can stress thread seats. Clean the pocket frequently with compressed air and apply high-temperature anti-seize compound to the M4 Torx screw threads. Do not over-torque past recommended ratings.
Workpiece Material Matrix
Fully optimized across standard industrial engineering material codes: P (Carbon, Low-Alloy & Pre-hardened Mild Steels), M (Austenitic, Ferritic & Duplex Stainless steel grades), K (Grey & Ductile Cast Irons), N (Precision Aluminum Blanks, Copper, Brass Alloys & Polymers), and S (High-Temperature Superalloys & Titanium Alloys).
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.