How to choose metal drill bits
When selecting metal drill bits, focus on these key specifications:
- Material: High-Speed Steel (HSS) is standard for general metal drilling. For harder metals like stainless steel, HSS-Cobalt bits offer superior heat resistance and durability. Titanium Nitride (TiN) coatings, found on some HSS-G bits, can extend bit life and improve cutting speed.
- Shank Type: Most bits feature a cylindrical shank for standard drill chucks. Hex shanks, like those on Milwaukee Shockwave bits, are designed for impact drivers, offering better grip and preventing slippage.
- Tip Geometry: A split point tip, such as Bosch's PointTeQ, helps prevent 'walking' when starting a hole, allowing for more precise drilling without a centre punch.
- Size: Bits are available in a wide range of diameters, from small 4.0mm or 4.5mm for pilot holes up to larger 12.0mm for bigger fixings. Consider whether you need individual bits or a set covering common sizes.
What you should expect to pay
Metal drill bits range from around £0.10 for individual smaller HSS bits up to £119.99 for comprehensive sets or specialist bits. For occasional DIY use, individual HSS bits or basic HSS sets in the £1-£20 range will likely suffice. A working tradesperson will benefit from investing in quality HSS-Cobalt or TiN-coated HSS-G sets, which typically fall in the £20-£60 range, offering better longevity and performance for regular use. Larger, multi-piece sets with premium materials will be at the higher end of the price spectrum.
Brands worth knowing
- Bosch: Known for reliable HSS and HSS Cobalt bits, often featuring innovative tip geometries like PointTeQ.
- Milwaukee: Strong reputation for durable hex-shank bits designed for impact drivers, such as their Shockwave range.
- DeWalt: Offers a good balance of performance and durability across their drilling accessories.
- Makita: Provides quality drilling solutions, often complementing their power tool range.
- Erbauer: A popular choice for solid, dependable bits, often representing good value.
- Irwin: Respected for their range of drilling and cutting tools, including quality drill bits.
