4-20mm HSS Step Drill Spiral Flute 2-Cutter 118° Point 90° Step Angle - Ruko GmbH

Precise step drilling from 4–20 mm with a spiral-fluted HSS geometry and nine progressive steps ensures efficient hole production. The cross-ground 118° tip and 90° step angle reduce walking and produce cleaner entries, while the shank with three flats provides secure clamping; order the RUKO step drill directly via Metav Werkzeuge or consult our specialists for application advice.

RUKO Step Drill 4–20 mm — HSS, spiral-fluted, 9-step

The RUKO Step Drill 4–20 mm is a high-speed steel, nine-step drill designed for progressive hole enlargement with precise centring and reliable clamping.

• HSS construction for high wear resistance
• Spiral-fluted for fast chip evacuation
• 9-step progression from 4 to 20 mm
• Shank with three flats for secure clamping

Faster holemaking with progressive steps and stable entry

The stepped geometry offers a progressive hole sizes approach that eliminates frequent tool changes and simplifies setup. With a 4–20 mm range arranged over 9 steps, the tool generates consecutive diameters in one pass, reducing cycle times and minimising repositioning. The cross-ground tip with a 118° point angle helps centre the cutter on first contact, lowering the need for pilot holes and improving first-hole accuracy. These design choices translate into measurable workflow gains when repeatable hole sizes are required on a production run.

Improved chip control and tool life from spiral flutes

Spiral fluting provides consistent chip evacuation and reduced heat build-up at the cutting zone, contributing to longer service periods between interventions. The combination of a spiral-fluted profile and two cutting edges balances cutting forces and produces smoother holes with less burring. Where reliable chip removal is essential to maintain dimensional quality, this geometry supports sustained machining performance and more predictable surface finishes.

Secure clamping and torsion resistance for consistent machining

The shank equipped with three flats ensures secure clamping in standard chucks and reduces the risk of slippage under torque. This mechanical lock improves concentricity and repeatability across multiple holes, which is particularly useful in tight-tolerance tasks. The stepped design and 90° step angle also promote gradual material engagement, lowering axial loads during enlargement and contributing to a steadier machining process.

Practical choice for workshop workflows and inventory consolidation

As a single-tool solution for a range of hole diameters, the stepped cutter supports leaner tooling inventories and faster job changeovers. The solid HSS construction combines toughness with ground geometry that maintains cutting performance across the step sizes. The compact profile and standard shank make the item straightforward to integrate into existing drill setups, offering a pragmatic option for maintenance, fabrication and general workshop applications where progressive holemaking is required.

For consistent step-drilling performance and tailored application advice, contact Metav Werkzeuge—Metav’s experts will assist with selection and supply of the RUKO step drill (SKU 4000601708NW); eMail: info@metav-werkzeuge.com | Tel: +49 2822 7131930

Technical data

• Article number: 4000601708NW
• Name: RUKO Step Drill 4–20 mm (HSS, 9 steps)
• Manufacturer: Ruko GmbH
• Packing unit: 1

Facts

• Diameter range: 4–20 mm
• Number of steps: 9
• Point angle: 118°
• Step angle: 90°
• Cutting edges: 2

Special features

• HSS material
• Spiral-fluted (twist-fluted)
• Cross-ground tip
• Shank with three flats
• 2-cutting-edge geometry

FAQ

What hole sizes does the tool cover?
The tool covers a continuous progression from 4 to 20 mm across nine defined steps, enabling multiple final diameters with a single cutter.

How many steps are included and what is the SKU?
The cutter features 9 steps and is listed as SKU 4000601708NW for easy identification in inventory systems.

How does the shank design improve machining reliability?
The shank with three flats secures the tool against rotation in standard chucks, improving concentricity and reducing slippage during drilling.

What benefits does the cross-ground 118° tip provide?
The cross-ground 118° tip improves centring on initial contact and minimises walking, which supports cleaner hole entries and reduces the need for pilot drilling.

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