4-12/4-20/4-30mm Step Drill Set HSS Spiral Flute With Cross Point, 3-Flatted Shank, Plastic Case - Ruko GmbH

Benefit from durable HSS construction and a spiral flute geometry that speeds chip evacuation while the split-point grind reduces walking — together these features support fast, accurate holemaking across stepped diameters. Order the set directly via Metav Werkzeuge or consult our specialists for application advice.

RUKO Step drill set Ø4–12 / Ø4–20 / Ø4–30 mm – HSS, spiral flute

The RUKO Step drill set Ø4–12/Ø4–20/Ø4–30 mm is a stepped drilling solution designed for precise hole enlargement and rapid size selection across a defined diameter range

• Spiral-fluted HSS for faster chip evacuation
• Split-point grind for precise centring
• Shank with three flats for secure clamping

Faster, cleaner holes thanks to spiral flutes and HSS hardness

The combination of HSS material and a spiral flute profile accelerates chip removal and maintains cutting edge life under continuous use. The spiral flute guides swarf away from the cutting edge, which reduces heat build-up and the need for frequent clearing during a run of drilled holes. With a split-point grind the starting behaviour improves markedly: less pre‑punching is needed because the tip centres reliably, leading to fewer slipped starts and cleaner entry holes. This technical pairing translates into measurable time savings on repetitive operations and a more predictable machining process.

Controlled sizing and secure clamping for repeatable results

Stepped geometry with defined step pitch values gives immediate control over hole increments: Ø4–12 = 1 mm, Ø4–20 = 2 mm, Ø4–30 = 2 mm. The pitch specification describes the axial distance between successive step diameters and therefore determines how quickly a target size is reached and how fine the size progression appears. The shank with three flats prevents rotation in the chuck or collet, ensuring repeatable concentricity and torque transmission during higher-load operations. These features help maintain consistent hole diameters and reduce rework.

Robust storage and practical handling to protect tool life

Delivered in an impact‑ and break‑resistant plastic case, the set stays organised and protected in transit or on the bench, reducing downtime caused by lost or damaged tools. The stepped drills are ready for immediate selection and return to storage, aiding efficient workflow in busy shops. Beyond the hardware, Metav’s quality filter in Emmerich ensures that precision tools arrive inspected and ready for industrial use, supporting reliable supply and straightforward replenishment when tool wear requires replacement.

Contact Metav Werkzeuge for availability and technical guidance on the RUKO HSS stepped drills — our specialists in Emmerich can advise on application details and delivery options

Technical data

• Article number: 4000601745NW
• Label: Step drill set Ø4–12 / Ø4–20 / Ø4–30 mm, HSS, spiral flute, 3-piece, plastic case
• Manufacturer: Ruko GmbH
• Packaging unit: 1
• UID: 4000601745NW

Numbers / Core technical data

• Diameters: Ø4–12 mm, Ø4–20 mm, Ø4–30 mm
• Step pitch: Ø4–12 = 1 mm; Ø4–20 = 2 mm; Ø4–30 = 2 mm

Special features / Versions

• Spiral-fluted geometry
• Split-point (cross) grind
• Shank with three flats
• Impact- and break-resistant plastic case

FAQ

What advantage does the spiral flute offer compared with straight-fluted stepped drills?
The spiral flute on this RUKO step drill set channels chips away from the cutting zone more efficiently, reducing heat and clearing swarf for more consistent cutting performance and longer tool life.

How do the step pitch values affect holemaking?
Step pitch (Ø4–12 = 1 mm; Ø4–20 = 2 mm; Ø4–30 = 2 mm) determines the axial spacing between successive diameters; finer pitch gives closer intermediate sizes, while larger pitch reaches larger diameters with fewer revolutions.

Does the drill set require special clamping?
The shank with three flats provides positive engagement in standard chucks and collets, enabling secure clamping and reliable torque transmission during use with the RUKO stepped drills.

How does the split-point grind improve performance?
The split-point (cross) grind reduces walking at the start of a hole and improves centring, which means fewer pilot holes and more accurate entry geometry for every pass.

How are the drills stored and protected during transport?
The set is supplied in an impact- and break-resistant plastic case that keeps the drills organised and guarded against damage while in transit or on the workshop bench.

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