For UK workshops and DIY projects, choosing the right cobalt drill bits can dramatically improve drilling performance in hard metals. This guide highlights top cobalt sets, comparing build quality, heat resistance and versatility to help you select the best value per hole.
| Product | Brand | Key Feature |
|---|---|---|
| STROTON Metric M42 8% 1-10mm 19pc | STROTON | Long-range stainless and hard metal capability |
| Bosch Professional 19-Pc HSS-Cobalt ProBox | Bosch | Wear resistance with two cutters and two flutes |
| HPMAISON True 5% Cobalt 13Pcs | HPMAISON | 1.5–6.5mm range, strong heat resistance |
| STROTON Metric M42 1.5–6.5mm 13pc | STROTON | Premium M42 8% cobalt for stainless steel |
| STROTON Imperial M35 17pc | STROTON | High hardness and fast drilling through stainless steel |
STROTON 1-10mm M42 19pc
The STROTON Metric M42 8% Cobalt set is built from premium M42 cobalt steel, rated around 68-70 HRC for increased heat, wear, and chip resistance. With a 3-step design, these bits are designed to cut through stainless steel, hard metals, aluminum, and plastic. The set typically offers faster drilling speeds and a lower cost per hole due to higher hole yield, making it a practical option for frequent metal drilling. This 19-piece range covers common metric sizes from 1mm to 10mm, offering broad applicability in metalworking and engineering tasks.
Bosch 19-Pc HSS-Cobalt ProBox
The Bosch Professional 19-piece HSS-Cobalt ProBox offers durable wear resistance and heat protection thanks to cobalt alloy and fully ground HSS. Two cutters and two flutes help remove chips efficiently, extending tool life. The cylindrical shank is compatible with three-jaw drill chucks, making these bits versatile for metal drilling tasks on stainless steel and similar hard materials. This ProBox set is designed for reliability in professional applications and demanding drilling environments.
HPMAISON True 5% Cobalt 13Pcs
The HPMAISON True 5% Cobalt set features M35 cobalt steel for extended tool life and improved heat resistance. A 135° split point plus straight shanks aids centering and reduces walking in hard metals. The kit’s 13 sizes (1.5mm to 6.5mm) cover common needs in stainless steel, cast iron, and other hard metals. This set is suitable for precise drilling in demanding applications, but users should monitor speed and heat to maintain optimal performance.
STROTON Metric M42 1.5–6.5mm 13pc
This STROTON set uses premium 8% cobalt (M42) for enhanced heat and wear resistance, specifically designed for stainless steel and hard metals, along with wood, aluminum, and plastic. The 1.5mm to 6.5mm size range with a three-step cutting design is aimed at high-efficiency drilling through tough materials. It emphasises reduced chip buildup and consistent performance in demanding metalworking tasks, with a focus on longer tool life despite higher upfront costs.
STROTON Imperial M35 17pc
The STROTON Imperial M35 set offers 5% cobalt with a hardness around 68 HRC, providing heat, wear, and chip resistance for stainless steel and hardened metals. The cutting edge has been ground three times, delivering improved durability and faster drilling performance. This 17-piece collection is designed for heavy-duty metalworking, including stainless steel, hardened steel, iron, and related alloys, with a focus on efficiency and long-term tool life.
STROTON Cobalt 13Pc Set
STROTON’s 13-piece set features M35 cobalt steel (5% cobalt) with 68 HRC. The design includes split-point and full ground processes to handle heavy-duty work and materials such as stainless steel, steel plate, iron sheet, and hard woods. The set claims up to triple the drilling efficiency and a lower cost per hole due to higher output, aligning with professionals seeking robust performance across multiple materials.
Buying Guide: Key Considerations For Cobalt Drill Bits
- Material composition: Higher cobalt content (M35/M42) increases heat resistance and tool life but may come at a higher upfront price. Choose based on workpiece hardness and frequency of use.
- Drill bit geometry: Split-point tips help prevent walking on hard metals. Fully ground bits improve chip clearance and cutting efficiency in stainless steel and cast iron.
- Coating and finish: Gold oxide and other finishes reduce friction and heat buildup, extending bit life under high-speed drilling.
- Shank and compatibility: Straight cylindrical shanks fit most three-jaw chucks. Verify chuck size to ensure proper fit and grip.
- Size range and versatility: Sets with a broad size range reduce the need to switch bits often and support a variety of tasks from pilot holes to larger through-holes.
- Usage guidelines: High-speed drilling through hard metals requires appropriate feed pressure, cooling (where applicable), and measured RPM to prevent bit damage and chip clogging.
- Value per hole: While individual cobalt bits may cost more, higher durability and faster hole production can lower overall project costs.
- Warranty and brand support: Reputable brands often provide clearer guidance, replacements, and compatibility with common drilling equipment in the UK market.