Drill bit Proline 78115K — metal bit Ø11.5 mm, length 142 mm, 1 pc

Proline 78115K is a single high-speed steel twist drill designed for metalworking, featuring an 11.5 mm diameter and a total length of 142 mm. The bit has a standard cylindrical shank compatible with handheld drills and drill presses, and is produced by grinding to ensure straightness and hole accuracy. The drill's geometry and material composition make it suitable for drilling a range of ferrous and non‑ferrous metals, including difficult-to-machine alloys.

Advantages

The drill bit is manufactured from premium HSS with 5% cobalt, offering increased hardness and high temperature resistance for extended cutting life. A 135° point angle with chamfering adjustment supports rapid centring and reduced walking at the start of drilling, while the precision grinding process ensures rectilinear holes and consistent performance. The standard shank design provides reliable clamping and compatibility with most chucks.

Suitable for

• Drilling holes in steel and stainless steels
• Working with high-alloy and acid-resistant metals
• Fabrication, maintenance and repair tasks in workshops and construction sites
• Use in handheld drills and bench drill presses for mid-sized holes

Key specifications

• Diameter: 11.5 mm
• Total length: 142 mm
• Point angle: 135° with chamfering adjustment
• Material: high-speed steel with 5% cobalt (HSS-Co)
• Manufacturing: fully ground flute geometry for high accuracy
• Suitable materials: high-alloy steels, titanium alloys, acid-resistant and stainless steels, cast iron and other hard-to-machine metals
• Suitable for use in handheld drills and drill presses

How to use

Secure the drill bit in the chuck of a handheld drill or drill press, ensuring firm and concentric clamping. Mark and, if necessary, centre-punch the drilling position to reduce walking. Use appropriate cutting speed and feed for the material being drilled; when working with stainless or high-alloy steels, use lower speeds and steady feed to avoid overheating. Apply suitable cutting fluid or lubricant for metal drilling to improve life and chip evacuation. After drilling, retract the bit while the spindle is still turning to clear chips and prevent clogging.

Usage recommendations

For best results on stainless and high-alloy steels, use a light cutting oil, moderate spindle speed, and steady pressure. Inspect the bit before use for straightness and wear, and replace when the cutting edge shows signs of dulling to maintain hole accuracy and reduce workpiece damage.