315 products
Metal Drill Bits
metal-drill-bits
TIMCO Ground Long Jobber Drills HSS M2 - 4.0mm (10pcs)
- Pack quantity
- 10 Pieces
- Price
- £12.13Incl. VAT
TIMCO Pozi Driver Bit S2 Grey - No.3 x 25 (100pcs)
- Pack quantity
- 100 Pieces
- Price
- £29.35Incl. VAT
Metal Drill Bits That Cut Clean and Last Longer
Using the wrong drill bit on metal can snap it in seconds. It can burn the tip, damage your workpiece, and waste your time. This range of heavy duty metal drill bits is built for tough jobs. It covers HSS drill bits, cobalt drill bits, step drill bits, and complete sets. All products are suited to steel, stainless steel, aluminium, cast iron, and other metals. Whether you are on a building site or in a home workshop, you will find the right bit here.
Metal Drill Bits Built for Trade and DIY Use
Drilling through metal is not the same as drilling through wood. Metal is harder and generates heat quickly. You need a bit that can handle both.
A good metal drill bit stays sharp under pressure. It cuts cleanly without wandering off line. It holds up across repeated use without dulling fast.
This range stocks reliable metal drill bits for UK tradespeople and DIYers. Products are available in single bits and full sets. You can get the exact size you need or a full set of metal drill bits for the workshop.
Quick tip: Always use a centre punch before drilling into metal. It stops the bit from skating across the surface. Start at a slow speed and increase gradually for a clean hole.
Types of Metal Drill Bits in This Range
Each type of metal drill bit is made for a different purpose. Here is a clear guide to what is available and when to use each one.
HSS Drill Bits (High Speed Steel)
HSS bits are the most common type for metal drilling. They work well on mild steel, aluminium, copper, and brass. They are affordable and widely used in trade and DIY. Good for general metalwork, pipework, and sheet metal jobs. Available in individual sizes and full sets.
HSS Cobalt Drill Bits
Cobalt bits are tougher than standard HSS. They contain between 5% and 8% cobalt alloy. This makes them heat-resistant and harder wearing. Ideal for drilling stainless steel, cast iron, and hardened metals. A top pick when standard HSS bits wear too fast.
TiN Coated Drill Bits
TiN stands for titanium nitride coating. This coating reduces friction and adds surface hardness. TiN coated bits last longer than uncoated HSS bits. They are suitable for mild steel, aluminium, and non-ferrous metals. The gold colour makes them easy to identify.
Step Drill Bits for Sheet Metal
Step bits drill multiple hole sizes in a single bit. They are ideal for thin sheet metal, electrical panels, and car bodywork. One step bit can replace several standard bits. They give a clean hole with no burring on thin materials. A useful addition to any metal drill bit set.
Metal Drill Bit Sets
A set of metal drill bits gives you a full range in one pack. Sets typically cover sizes from 1mm up to 13mm. They come in a plastic case or indexed holder. The best metal drill bit set covers the most common sizes for site and workshop use. Sets save money compared to buying individual bits.
Long Series Metal Drill Bits
Long series bits reach further into deep holes. They are used when a standard length bit cannot reach. Common in plumbing, electrical, and structural steelwork. They require a slower feed rate to avoid flexing. Always support the bit near the tip when possible.
How to Pick the Right Metal Drill Bit
The right bit depends on the metal you are drilling. It also depends on your drill and how often you drill.
Drilling Mild Steel
A standard HSS bit works well for mild steel. Use a cutting fluid or WD-40 to reduce heat. Keep the speed moderate and apply steady pressure. A TiN coated bit will last longer if you drill mild steel often.
Drilling Stainless Steel
Stainless steel is harder and work-hardens quickly. Use a cobalt drill bit for stainless steel. Drill slowly with firm, consistent pressure. Do not let the bit spin without cutting. It will harden the surface.
Drilling Aluminium
Aluminium is soft but can clog the flutes of a bit. Use a standard HSS bit at a higher speed. Apply a small amount of cutting fluid. Clear the flutes often to stop build-up.
Drilling Sheet Metal
Thin sheet metal needs care to avoid tearing. A step drill bit gives the cleanest result. Back the sheet with a piece of scrap wood. This stops the bit from grabbing at breakthrough.
Drilling Cast Iron
Cast iron is brittle and abrasive. Use a cobalt or TiAlN coated bit. Do not use cutting fluid on cast iron. Drill dry at a slow, steady speed.
High Volume or Trade Use
If you drill metal regularly, invest in cobalt bits. A heavy duty metal drill bit set will cover all your common sizes. Cobalt bits stay sharp much longer under repeated use. They cost more but last significantly longer.
Metal Drill Bit Types at a Glance
Not sure which type to buy? This table makes it simple.
| Bit Type | Best For | Key Benefit |
|---|---|---|
| HSS (High Speed Steel) | Mild steel, aluminium, brass, copper | Affordable and versatile for general use |
| HSS Cobalt | Stainless steel, cast iron, hardened metals | Heat-resistant and longer lasting |
| TiN Coated HSS | Mild steel and non-ferrous metals | Reduced friction, longer service life |
| Step Drill Bit | Sheet metal, electrical panels, bodywork | Multiple sizes in one bit, clean holes |
| Long Series HSS | Deep holes in metal structures | Extended reach for hard-to-access spots |
For everyday metalwork, HSS bits are a solid starting point. For tougher metals or heavy use, cobalt is worth the upgrade.
Drill Speed and Technique for Metal Drilling
Getting the speed right is just as important as the bit itself. Too fast and you burn the tip. Too slow and you do not cut cleanly.
As a general rule, smaller bits need higher speeds. Larger bits need slower speeds with more pressure. Harder metals always need a slower speed than softer ones.
Here is a simple guide to starting speeds for metal drilling:
| Bit Size | Mild Steel (RPM) | Stainless Steel (RPM) | Aluminium (RPM) |
|---|---|---|---|
| 1mm to 3mm | 2,000 to 3,000 | 800 to 1,200 | 3,000 to 5,000 |
| 4mm to 6mm | 1,000 to 1,800 | 400 to 700 | 2,000 to 3,500 |
| 7mm to 10mm | 600 to 1,000 | 200 to 400 | 1,200 to 2,000 |
| 11mm to 13mm | 300 to 600 | 100 to 250 | 800 to 1,500 |
Pro tip: Use cutting fluid when drilling steel or stainless steel. It cools the bit, reduces friction, and gives a cleaner hole. Even a drop of WD-40 helps extend bit life noticeably.
Signs Your Metal Drill Bit Needs Replacing
A worn bit makes drilling harder and less accurate. It can also damage your workpiece or your drill.
Takes Longer to Drill
If a hole that used to take 10 seconds now takes 30, the bit is blunt. A sharp bit cuts quickly with moderate pressure. Forcing a blunt bit causes more heat and more wear.
Squealing or Burning Smell
A squealing sound or a burning smell means too much heat. This happens when the cutting edge is dull. Stop immediately and swap the bit before it damages your work.
Bit Wanders on Entry
A sharp bit grips on contact with a centre punch mark. A blunt or damaged bit skates sideways on entry. This ruins accuracy and scratches the metal surface.
Visible Tip Damage
Look at the tip under light. A sharp bit has clean cutting edges. Chipped, rounded, or discoloured tips mean it is done. Discolouration from heat shows the temper has gone.
Find the Right Metal Drill Bit for Your Job
Use the filters above to sort by bit type, size, and material. Check individual product pages for full specifications before ordering.
Whether you need a single cobalt bit for stainless steel, a step bit for sheet metal, or a full set of metal drill bits for the workshop, this range covers the most-used sizes and types for trade and DIY use across the UK. For jobs that also involve fixing into masonry, see our masonry drill bits range.
Frequently Asked Questions
What is the best metal drill bit for stainless steel?
A cobalt drill bit is the best option for stainless steel. Cobalt alloy handles the heat that stainless steel generates. Drill slowly with firm pressure and use cutting fluid.
What does HSS mean on a drill bit?
HSS stands for high speed steel. It is a tool steel grade designed to withstand heat during cutting. HSS bits are the standard type used for drilling metal in the UK.
Can I use a wood drill bit on metal?
No. Wood bits are not hard enough for metal. They will blunt immediately on contact with steel. Always use a bit rated for metal drilling.
What size drill bit do I need for an M6 bolt hole in metal?
For a clearance hole for an M6 bolt, use a 6.5mm drill bit. For a tapped hole (to cut a thread), use a 5mm drill bit. Always check a standard metric drill chart for exact sizes.
What is the difference between HSS and cobalt drill bits?
HSS bits are made from high speed steel and suit most common metals. Cobalt bits contain cobalt alloy, which makes them harder and more heat-resistant. Cobalt bits cost more but last longer on tough or hardened metals.
Do I need cutting fluid when drilling metal?
Cutting fluid is strongly recommended for steel and stainless steel. It cools the bit, reduces friction, and extends bit life. It is not needed for aluminium or cast iron.
What is a good all-round set of metal drill bits for the UK?
A good set covers 1mm to 13mm in 0.5mm steps. Look for HSS or HSS cobalt bits in an indexed case. A heavy duty metal drill bit set with cobalt tips suits both trade and workshop use.
Related Drill Bits and Cutting Tools
Metal drill bits are often used alongside other cutting tools. See our full drill bits range for wood, masonry, and multi-material options.
If you also work with fixings after drilling, visit our screws range for the right fastener for every material.