RUKO STB-HSSCo-Ø5/16-1-Zoll Step Drill Bit (5-16 mm, HSS-Co 5% Cobalt)

Drill precise, burr-free holes from 5 to 16 mm in thin materials with this HSS-Co step drill bit, featuring 10 cutting steps and a self-centering cross-ground point for fast, accurate starts.

Overview

The RUKO STB-HSSCo-Ø5/16-1-Zoll is a high-performance step drill bit made from HSS-Co high-speed steel with 5% cobalt. It is designed for drilling sheet metal, non-ferrous metals, plastics, and other thin materials up to 4 mm thick. The bit has a cylindrical shank with a diameter of 8 mm, a total length of 70 mm, and a working length of 40 mm. The point angle is 118°, and the cross-ground point ensures self-centering without a pilot hole. The bright, uncoated surface reduces friction and aids chip evacuation. Use with corded or cordless drills and drill presses; coolant is recommended for optimal performance.

What stands out

• 5% cobalt HSS for high heat resistance and extended tool life
• 10 steps from 5 mm to 16 mm in 1 mm increments
• Self-centering cross-ground point eliminates the need for center punching
• Two cutting edges for clean, round holes
• Bright finish for smooth cutting and easy chip flow

Technical details

• Drill Type: Step Drill Bit
• Material: HSS-Co (High-Speed Steel with Cobalt)
• Cobalt Content: 5%
• Drilling Diameter Range: 5 - 16 mm
• Number of Steps: 10
• Step Diameters: 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 mm
• Shank Type: Cylindrical
• Shank Diameter: 8 mm
• Total Length (L1): 70 mm
• Working Length (L2): 40 mm
• Point Angle: 118°
• Drill Point: Cross-ground point
• Self-Centering Tip: Yes
• Cutting Edges: 2
• Surface Finish: Bright (Uncoated)
• Application: Sheet metal, non-ferrous metals, plastics, thin materials
• Maximum Material Thickness: 4 mm
• Tool Compatibility: Corded/Cordless Drills, Drill Presses
• Coolant Use: Recommended for optimal performance and tool life
• Packaging: Single piece

Our verdict

A professional-grade step drill for clean, accurate holes in thin stock. The cobalt alloy and self-centering tip make it a reliable choice for repeated use.