31mm Countersink 90° HSS 4-Flute RUnaTEC Coating, Right-Hand Shank With 3 Flats - Ruko GmbH

Take advantage of a high-speed HSS construction with RunaTEC coating and a four-flute geometry to achieve faster, quieter and more consistent 90° countersinking in steel; procure the tool via Metav Werkzeuge or consult our specialists for application advice.

ULTIMATECUT 4S Countersink, 31 mm, 90° — Ruko

The ULTIMATECUT 4S Countersink is a precision 90° HSS tool for professional countersinking in steel, optimised for both stationary machines and manual drilling operations

• HSS with RUnaTEC coating
• 90° precision countersink angle
• 4-flute design for smooth finish
• Reduced feed force, quieter operation

High-performance countersinking that speeds production without sacrificing finish

The four-flute geometry combined with HSS substrate and a RunaTEC surface treatment delivers a tangible productivity advantage: the geometry reduces cutting forces and improves chip evacuation, enabling up to 50% faster countersinking cycles and up to 3x more countersinks per tool compared with conventional designs. The 90° angle and 31 mm diameter are matched to common fastener heads and deburring operations, producing a consistent profile. This results in fewer tool changes, reduced cycle times and a direct impact on throughput in both small-batch and continuous production environments.

Lower effort and steadier handling for manual and machine use

Designed with a shank with 3 flats for secure clamping and a right-hand cutting direction, the geometry is tuned to demand reduced feed force while preserving cutting stability. The specified feed in steel — 0.25 mm/rev at cutting forces up to 800 N — gives a clear, measurable starting point for setting feeds and speeds on bench drills and pillar machines; feed values are expressed as millimetres per revolution to simplify conversion from spindle speed. The tool runs quieter than comparable countersinks, which reduces vibration transfer to the spindle and the workpiece and helps to eliminate chatter marks for an improved surface result.

Material suitability and finish quality for demanding workshop use

Manufactured to DIN 335C standards and optimised for processing steel, the design favours a clean countersink profile and reliable lifetime under mixed application conditions. The coated cutting edges maintain edge stability and allow operators to concentrate on aligning and positioning rather than compensating for tool wear. The result is an optimal countersink finish with minimal burring, particularly beneficial for assembly-ready components where visual and functional conformity matter. As a practical partner, Metav Werkzeuge supports selection and integration into workplace processes to ensure consistent results.

Speak with Metav Werkzeuge in Emmerich for tailored application advice and procurement of Ruko countersinks to match specific workshop requirements

Technical data

• Article number: 4000605557NW
• Item label: Kegelsenker ULTIMATECUT 4S DIN 335C 90Grad D.31mm HSS RUnaTEC Z.4 RUKO
• Manufacturer: Ruko GmbH
• Packaging unit: 1
• UID: 4000605557NW

Facts

• Diameter: 31 mm
• Countersink angle: 90°
• Cutting edges: 4
• Feed in steel (≤800 N): 0.25 mm/rev
• Packaging unit: 1

Special features

• HSS material
• RUnaTEC-coated
• DIN 335C
• Shank with 3 flats
• Right-hand cutting
• Optimised for stationary and manual use
• Reduced feed force
• Quiet run
• Optimal countersink finish without chatter

FAQ

What materials can this countersink process reliably? The ULTIMATECUT 4S Countersink is optimised for steel, providing robust cutting performance and a consistent countersink profile when used within the recommended feed parameters.

What is the recommended feed value for steel? For steel applications up to 800 N the specification indicates a feed of 0.25 mm/rev, which should be used as a starting point when setting spindle speed and feed rate.

How does the RUnaTEC coating benefit workshop workflows? The RunaTEC coating increases tool life and reduces friction, allowing the Ruko countersink to maintain edge stability and produce more countersinks per tool in both manual and machine operations.

Is the shank suitable for secure clamping in standard chucks? Yes, the shank with 3 flats is designed for secure clamping in drill chucks and collets, reducing slippage during manual or machine use.

Which standard does the tool comply with for profile and geometry? The countersink conforms to DIN 335C, ensuring an industry-standard geometry for reliable fastener seating and repeatable results.

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