Drill bit Proline 12 mm, length 151 mm, model 79120K, 1 pc

Proline 12 mm drill bit, overall length 151 mm, model 79120K, is a single HSS metal drilling tool intended for precise holemaking in steel and similar materials. With a 12 mm diameter and long shank, it fits handheld drills and drill presses to perform through-holes, maintenance work, metal fabrication and routine workshop repairs that require a clean 12 mm opening.

Advantages

The drill bit features a 135° point angle with chamfering adjustment to enable fast penetration and improved centering without excessive wandering, reducing time spent on centre punching. Ground cutting edges provide consistent cutting performance and longer usable life, while refined high-speed steel (HSS) construction offers a balance of hardness and toughness suitable for drilling into ferrous and non-ferrous metals. The product is supplied in a blister pack for safe storage and easy handling.

Suitable for

• Drilling through-holes in mild steel, stainless steel and non-ferrous metals
• Workshop repairs and maintenance tasks requiring a 12 mm hole
• Metal fabrication, assembly and fitting operations
• Use with handheld electric drills and benchtop drill presses

Key specifications

• Diameter: 12 mm
• Overall length: 151 mm
• Material: refined high-speed steel (HSS)
• Point geometry: 135° point angle with chamfering adjustment
• Cutting edges: precision ground
• Packaging: single piece in blister pack

How to use

Secure the workpiece and mark the drilling position. For best results, use a center punch before drilling to improve initial centring. Mount the 12 mm HSS drill bit in the chuck of a handheld drill or drill press, ensuring it is tightened and aligned. Select a suitable cutting speed and apply steady pressure; use cutting fluid when drilling tougher steels or when prolonged drilling is required to reduce heat and extend bit life. Withdraw periodically to clear chips and allow cooling.

Usage recommendations

For prolonged tool life and consistent hole quality, use appropriate cutting speeds for the material, apply cutting fluid on harder metals, and avoid excessive feed rates that can cause overheating or breakage. Store the drill bit in its blister pack when not in use to protect the ground edges.