15mm Countersink UltimateCut 4-Flute HSS RUnaTEC Coated 90° Shank With 3 Flats - Ruko GmbH

Combining high-speed steel construction with a RUnaTEC coating and four-flute geometry delivers fast, low-force countersinking with a consistent, chatter-free finish; order directly via Metav Werkzeuge or consult their specialists for availability and technical guidance.

**ULTIMATECUT 4S Countersink (HSS, RUnaTEC-coated, 90°, Ø15 mm) by Ruko

The ULTIMATECUT 4S is a high-performance 4-flute conical countersink, designed for efficient steel countersinking in both stationary machines and hand-held tooling applications

• HSS with RUnaTEC coating
• 4-flute geometry for smooth cutting
• 90° countersink for standard chamfers
• Reduced feed force, higher throughput

Faster countersinking with reduced feed effort

The combination of HSS substrate and RUnaTEC coating reduces friction and heat at the cutting edge, enabling a significantly lower feed requirement and a higher production rate. With a specified 0.16 mm/rev feed capacity in steel up to 800 N and claims of up to 50% faster countersinking compared with conventional countersinks, throughput improves while operator effort falls. The four-flute design converts cutting action into a continuous, low-vibration operation that shortens cycle times in both manual and stationary workflows.

Consistent, chatter-free finish for visible quality gains

An optimised cutting geometry yields an extremely smooth run and an optimised countersink finish without chatter marks, giving immediate visual and functional benefits for subsequent assembly or fastening steps. The standard 90° angle produces a reliable chamfer compatible with most screw heads and countersunk fasteners; the multiple cutting edges distribute load evenly to avoid local overheating and serrated edges, preserving component tolerances and surface appearance.

Workshop-ready design for reliable clamping and machining

The tool’s shank with 3 flats secures grip in chucks and collets, reducing slippage during high-torque operations. Conforming to DIN 335 C, the geometry and dimensions meet recognised industrial standards for conical countersinks. The cutter is right-hand cut and primarily intended for the machining of steel, making it suitable for a wide range of metalworking tasks in production, maintenance and toolroom environments.

Practical productivity and service-life advantages

Fewer rework cycles and less operator fatigue translate into measurable savings: the tool supports up to 3× more countersinks per life cycle and runs noticeably quieter during cutting, which benefits both machine uptime and workshop environment. Durable construction and the coated surface extend edge life, reducing tool change frequency and supporting a predictable maintenance rhythm—advantages that contribute directly to leaner processes and steadier output.

Choose the Ruko ULTIMATECUT 4S for faster, quieter countersinking — contact Metav Werkzeuge for stock information or technical advice at info@metav-werkzeuge.com or call +49 2822 7131930

Technical data

• Article number: 4000605551NW
• Product: ULTIMATECUT 4S Countersink
• Manufacturer: Ruko GmbH
• Packaging unit: 1

Facts

• Diameter: 15 mm
• Countersink angle: 90°
• Flutes: 4
• Feed in steel (up to 800 N): 0.16 mm/rev
• Standard: DIN 335 C

Special features

• Material: HSS
• Coating: RUnaTEC
• Right-hand cut
• Shank with 3 flats
• Suitable for steel
• Extremely quiet, smooth run
• Optimised countersink finish without chatter marks
• For stationary and manual use

FAQ

Which materials can be machined with this countersink? The Ruko ULTIMATECUT 4S is specified for the machining of steel and is optimised for conventional workshop steels, delivering controlled cutting and long edge life.

What does the DIN 335 C designation mean for this tool? DIN 335 C denotes the conical countersink geometry and tolerances; the ULTIMATECUT 4S conforms to that standard, ensuring compatibility with industry expectations for fit and chamfer angle.

How does the RUnaTEC coating improve performance? The RUnaTEC coating reduces friction and thermal load at the cutting edge, which for the ULTIMATECUT 4S results in lower feed force, extended tool life and a quieter cutting process.

Is the shank suitable for standard chucks and collets? Yes; the shank with three flats improves clamping security in chucks and collets, reducing slippage during both hand-held and machine-mounted operations.

Can this countersink be used for hand-held operations as well as on machines? The design of the ULTIMATECUT 4S supports both manual and stationary use, offering smooth running characteristics and reduced operator effort across applications.

Manufacturer/Responsible: Ruko GmbH Präzisionswerkzeuge, Robert-Bosch-Strasse 7, 71088 Holzgerlingen