RUKO STB-HSS-TiN-4,0-39,0mm Twist Drill Bit, 4.0 mm, TiN Coated, DIN 338

For machinists and metalworkers drilling precise 4.0 mm holes in steel, cast iron, non-ferrous metals, or plastics, the RUKO STB-HSS-TiN-4,0-39,0mm twist drill bit delivers reliable performance. Its titanium nitride coating reduces friction and heat, extending tool life and improving chip evacuation in demanding workshop environments.

Key specifications

• Drill bit type: Twist drill bit
• Diameter: 4.0 mm
• Material: High-speed steel (HSS)
• Coating: Titanium nitride (TiN)
• Standard: DIN 338
• Type: N (standard helix angle)
• Shank type: Cylindrical (straight shank)
• Point angle: 118°
• Cutting direction: Right-hand cutting
• Overall length: 75 mm
• Working length: 39 mm
• Manufacturing process: Ground
• Colour: Gold
• Recommended materials: Steel, cast iron, non-ferrous metals, plastics
• Packaging unit: 1 piece

Why choose it

The TiN coating provides a hard, low-friction surface that resists wear and helps the drill bit stay sharp longer than uncoated HSS bits. The precision ground flutes ensure accurate hole sizing and smooth chip flow, making it a dependable choice for both manual and CNC drilling operations.

Ideal use cases

• Drilling mounting holes in steel brackets and frames
• Creating pilot holes for tapping in cast iron components
• Machining non-ferrous metals like aluminium and brass
• Drilling plastic enclosures without cracking

Good to know

The DIN 338 standard guarantees consistent dimensions and performance. The 118° point angle is suitable for general-purpose drilling in a wide range of materials. Use appropriate cutting fluid when drilling steel to maximise tool life.