Metal drill bit set
Updated: 2026-10-23
You have a cordless drill, a mild-steel bracket on the bench, and a packet that says HSS, cobalt, black and gold in the same breath. A metal drill bit set is worth buying only after you name the metal, read the point, and match the diameters to the holes you will actually drill. Price comes last. The [metal drill bit comparison](/hub/drilling-and-accessories/metal-drill-bit) ranks nine amazon.co.uk listings saved on 19 October 2026, from £3.99 to £17.99. This page is the order of those questions, not a second ranking. A qualifying purchase can earn a commission at no extra cost to you.
You have a cordless drill, a mild-steel bracket on the bench, and a packet that says HSS, cobalt, black and gold in the same breath.
You have a cordless drill, a mild-steel bracket on the bench, and a packet that says HSS, cobalt, black and gold in the same breath. A metal drill bit set is worth buying only after you name the metal, read the point, and match the diameters to the holes you will actually drill. Price comes last. The metal drill bit comparison ranks nine amazon.co.uk listings saved on 19 October 2026, from £3.99 to £17.99. This page is the order of those questions, not a second ranking. A qualifying purchase can earn a commission at no extra cost to you.
Our top picks
| Badge | Product | Grade | Diameters | Point | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  Bosch Bosch PointTeQ 19-piece HSS set | HSS PointTeQ, not cobalt | 1.0–10.0 mm, 0.5 mm steps | n/a | 9.0 | about £14.12 | View offer |
| Best value |  Bosch Bosch PointTeQ 18-piece ToughBox | HSS PointTeQ | 1–10 mm, duplicates at 2, 3 and 4 mm | 135° | 9.0 | about £11.95 | View offer |
| Alternative |  DeWalt DeWalt DT5912 13-piece HSS-R | HSS-R black oxide in the title; material cell says chrome vanadium | 1.5–6.5 mm | 118° | 9.0 | about £9.60 | View offer |
On this page
Name the metal before the brand
Mild steel, aluminium and plastic are an ordinary high-speed steel job. Cutwel puts standard HSS on general steels, cast iron and non-ferrous metal, and reserves HSSE, about 5% cobalt in M35, for stainless or alloy steel you cut regularly. Thürmer draws the same line: HSS-Co earns its place when the metal is harder and hotter at the edge. You do not need cobalt for mild-steel shelf brackets. You do if last month’s HSS bit came out blue from a stainless sink. About 5% is M35 and about 8% is M42. Above about 45 HRC, Thürmer says HSS will not cut. If you cannot tell the alloy from the finish, read HSS vs cobalt drill bits before you add anything to the basket.
Read the point, then ignore DIN 338 as a grade test
Bosch’s GB PointTeQ page states DIN 338, a 135° tip and black oxide, and it does not claim cobalt. DeWalt’s UK page for DT5912-QZ states HSS-R, 118°, 1.5 mm to 6.5 mm, and metals up to 900 N/mm². On amazon.co.uk the material cell says chrome vanadium steel. Report both lines. DIN 338 and BS 328 are jobber length and a straight shank, not a cobalt test, and BS 328 is not a Kitemark. The Bosch 19-piece listing leaves the angle blank even though the GB page says 135°.
Match the diameters to the holes
A set that stops at 6.5 mm cannot drill an 8 mm hole. DeWalt DT5912-QZ lists 1.5 mm to 6.5 mm and nothing larger. The Bosch 19-piece ProBox, at £14.12, runs 1.0–10.0 mm in 0.5 mm steps. The Bosch 18-piece ToughBox, at £11.95, duplicates 2, 3 and 4 mm and has no 6.5, 7.5, 8.5 or 9.5 mm. Janzoom is a 1/8 in pair, MOXPIFY and Misuyue are 1 mm packs, and STROTON is four 5 mm bits. None replaces a 1–10 mm case. Which listing fits you is on best metal drill bits.
Separate the making process from the alloy
HSS-R means the flutes were roll-formed. HSS-G means they were ground. HSS-Co, also written HSS-E, means cobalt is in the steel. A black or gold colour is a fourth fact. DeWalt’s DT5912 is HSS-R plus black oxide. Bosch PointTeQ in this sample is black-oxide HSS, not the Bosch HSS-Co range. A gold photo is often titanium nitride, and grinding the tip removes that coat while cobalt in the alloy stays. Lines such as 68 HRC are untested claims here.
What this sample can spend
On 19 October 2026 the nine listings were £3.99 to £17.99. Entry is £3.99–£4.59 for one diameter. The mid band is £9.60–£14.12 for DeWalt and the two Bosch HSS sets. The cobalt-claimed sets are £16.87–£17.99. A later snippet on DT5912 showed £9.12. That is price drift, not a new comparison figure. Bosch HSS-Co sets on the GB site were about £24.68 to £68 including VAT on 22 October 2026, and they are not in this sample.
Common questions
Do I need cobalt drill bits for mild steel brackets?
No. Mild steel, aluminium and plastic are an ordinary HSS job. Cobalt alloy, about 5% in M35 or about 8% in M42, earns its place on stainless, high-tensile steel, or a seized bolt that has already blunted HSS. Cutwel and Thürmer draw that line. A gold photo does not change it.
What is the difference between a 118° point and a 135° split point?
A 135° split point starts with less skating on metal. A 118° point is the general-purpose angle. DeWalt’s DT5912 page states 118°. Bosch’s GB PointTeQ page states 135°. The angle is geometry. It can appear on plain HSS and on cobalt alloy, so it does not tell you which steel you are holding.
Does DIN 338 mean the bit is cobalt?
No. DIN 338 and BS 328 describe jobber length and a straight shank. They are not a cobalt test, and BS 328 is not a Kitemark. Bosch PointTeQ sets in this sample are DIN 338 HSS with black oxide, not the separate Bosch HSS-Co range. Read the grade line, not the standard number.
Will a set that stops at 6.5 mm drill an 8 mm hole?
No. DeWalt DT5912-QZ lists diameters from 1.5 mm to 6.5 mm, including 3.2, 3.5 and 4.8 mm, and nothing larger. An 8 mm or 10 mm hole needs a set that actually contains that size, such as the Bosch 19-piece run of 1.0–10.0 mm in 0.5 mm steps. The bit cannot drill a diameter it does not have.
When do half-millimetre sizes matter?
They matter for tapping pilots and for any drawing that names 6.5 mm rather than 6 mm. The Bosch 19-piece includes those half steps up to 10 mm. The 18-piece duplicates 2, 3 and 4 mm and skips 6.5, 7.5, 8.5 and 9.5 mm. If you only drill 5 mm clearance holes, the missing halves will not bother you.
Should I buy a full set or a pack of the one size I keep losing?
Buy the one size when that diameter is the one that snaps or walks off. Janzoom is a 3.2 mm pair, STROTON is four 5 mm bits, and the 1 mm packs are only 1 mm. A full set is the better buy when you do not yet know next month’s hole, as long as the largest size in the case is one you will use.
Related pages
Sources
Public sources from the research digest, dated 22 October 2026. Shelf prices, stars and review counts are the amazon.co.uk figures saved on 19 October 2026.
- Thürmer Tools, Drills FAQ (retrieved 22 October 2026)
- DeWalt UK, DT5912-QZ HSS-R set (retrieved 22 October 2026)
- Bosch Professional GB, PointTeQ HSS sets (retrieved 22 October 2026)
- Bosch Professional GB, HSS-Co twist drill bit sets (retrieved 22 October 2026)
- HSE, HSG129 health and safety in engineering workshops (retrieved 22 October 2026)
- The Personal Protective Equipment at Work Regulations 1992 (retrieved 22 October 2026)
- BSSA, speeds and feeds for drilling stainless steels (retrieved 22 October 2026)
- Heller, HSS-Co DIN 338 drill bits (retrieved 22 October 2026)