Ever tried drilling into tough metal and felt your drill bit just spin, refusing to bite? That frustrating moment is something many DIYers and professionals know well. Choosing the wrong metal cutting drill bit can mean wasted time, damaged materials, and a whole lot of headache. It’s not just about finding *a* drill bit; it’s about finding the *right* one for the specific metal you are tackling.
The world of metal drilling is filled with confusing terms like High-Speed Steel (HSS), Cobalt, and Titanium Nitride coatings. Picking the wrong tool for steel, aluminum, or stainless steel leads to overheating, dull edges, and poor hole quality. We understand the pain of a job going sideways because of a simple equipment mistake.
This guide cuts through the confusion. We will break down the essential types of metal cutting drill bits, explaining exactly what each one does best and when you should use it. By the end of this post, you will confidently select the perfect bit for any metal project, ensuring clean, efficient holes every single time. Let’s dive into the secrets of sharp drilling.
Top Metal Cutting Drill Bits Recommendations
- Titanium Nitride Coating Pilot Point for Longer Life
- Starts on contact for cleaner holes
- No spin shanks
- Tapered web provides greater durability to reduce breaking
- Includes sizes from 1/16-inch to 1/2-inch in a plastic tough case
- HSS Titanium Coating: The step drill has excellent sharpness and durability due to its high speed steel material and titanium coating
- 118° Split Point Tip & Dual-flute Design: increases cutting speed with self-centering and prevents walking, clears chips faster and allows particles to escape easily
- 50 Sizes in 5 Pcs: The step drill bit kit includes 5 standard pieces with totally 50 sizes for versatility, enough for your DIY needs
- Widely Application: Ideal for drilling holes in plastic, aluminum, iron and many other types of sheet metal (Not recommended for stainless steel & wood)
- Equipped with a well-organized case, make it more convenient for using and storing the step drills
- M35 Cobalt Drill Bit: Premium High Speed Steel M35 (Cobalt 5%) offers superior heat resistance and greater hardness compared to ordinary drill bits. It can extend the tool's service life when drilling hard materials.
- 135° Split Point Design: The cobalt drill bit set can be used effectively on most soft and hard objects, with a 135 degree point tip with round straight shank, self-centering to prevent walk-off , make drilling precise and faster.
- Efficient Drilling: Fully Ground twist design helps clear particles faster, decreases friction and heat for a cooler drilling performance.
- Various Sizes: 29 sets of drill bits include "1/16"，5/64"，3/32"，7/64"，1/8"，9/64"，5/32"，11/64"，3/16"，13/64"，7/32"，15/64"，1/4"，17/64"，9/32"，19/64"，5/16"，21/64"，11/32"，23/64"，3/8"，25/64"，13/32"，27/64"，7/16"，29/64"，15/32"，31/64"，1/2", can meet more needs.
- Widely Used: M35 Cobalt High Speed Steel is more suitable for tough, high tensile strength material. Particularly successful in cutting harden metals such as stainless steel, cast iron, high temperature alloy, titanium alloy, hard plastics and woods.
- Various Sizes: 13 sets of drill bits include 1/16", 5/64", 3/32", 7/64", 1/8", 9/64", 5/32", 11/64", 3/16", 13/64", 7/32", 15/64", 1/4", can meet more needs
- M35 Cobalt Drill Bit: The M35 cobalt drill bit is a durable, sharp and robust drill bit suitable for cutting stainless steel, iron castings, copper, aluminum and other soft metals as well as plastics, wood etc
- Quick and Efficient: The cobalt drill bit set can be used effectively on most soft and hard objects, with a 135 degree point tip and twist design for faster cutting, self-centering to prevent walk-off and faster chip and particle removal
- HSS Drill Bit Set: HSS cobalt drill bit set for hardened steel with excellent cutting performance. 13 sets of drill bits for long term use. The inserts are hardened and polished for improved sharpness and precise cutting without wobbling
- Easy Storage: The drill set includes a drill case with size indexes and is packaged in a small package for easy storage and sorting. If you have any questions, please refer to us and we will be happy to help you
- 135 Degree Split point tip design to help reduce walking
- High Speed Steel to be used in plastic, wood, and metal
- Tapered web design for extreme durability and resisting breakage
- Black and gold coating to help prevent rust and wear
- 3-Flats shank to reduce spin-out in the chuck on sizes larger than 3/16-in
- 【Cost-effective combination】: Pro edge 13pcs jobber drill bits set includes 13 sizes from 1/16" to 1/4" in 1/64" increments.With an average price per bit lower than the M35 Jobber Drill Bits market average price.
- 【M35 HSS】Pro edge 13pcs jobber drill bits set made of M35 material, which contains 5% cobalt, has higher wear resistance and heat resistance(3-5x Longer Life than M2 HSS Drill Bits).
- 【135° Split Point & Twist Design】: The 135 degree design reduces the pressure required for the drill bit to penetrate materials, making it more suitable for hard materials and helping the drill bit self locate and not easily shake, ensuring machining accuracy. Twisted design allows for faster removal of debris.
- 【Can Be Widely Used】: Suitable for cutting stainless steel, cast iron parts, copper, aluminum, and other soft metals, as well as plastics, wood, etc., whether it is woodworking, metal processing, home maintenance, or DIY, it can be easily handled.
- 【Purchase Benefits】: The Jobber drill bits set includes a sturdy and aesthetically pleasing packaging box for easy storage and classification. Make sure you pull up the tab on the top of the case when opening to avoid damage. If you have any questions, please contact us and we are happy to assist you.
- M35 Cobalt Drill Bit: Premium High Speed Steel M35 (Cobalt 5%) offers superior heat resistance and greater hardness compared to ordinary drill bits. It can extend the tool's service life when drilling hard materials.
- 135° Split Point Design: The cobalt drill bit set can be used effectively on most soft and hard objects, with a 135 degree point tip with round straight shank, self-centering to prevent walk-off, make drilling precise and faster.
- Efficient Drilling: Fully Ground twist design helps clear particles faster, decreases friction and heat for a cooler drilling performance.
- Various Sizes: 15 sets of drill bits include 1/16"x2pcs, 5/64"x2pcs, 3/32"x2pcs, 7/64", 1/8", 9/64", 5/32", 11/64", 3/16", 1/4", 5/16", 3/8", can meet more needs.
- Widely Used: M35 Cobalt High Speed Steel is more suitable for tough, high tensile strength material. Particularly successful in cutting harden metals such as stainless steel, cast iron, high temperature alloy, titanium alloy, hard plastics and woods.
- Enhanced M42 Alloy Material: These drill bits for metal contain an 8% cobalt alloy that delivers 10x life vs. Standard bits
- Cobalt M42 Drill Bit: Provides upgraded M42 cobalt drill bits, jobber-length bits designed for durability, high heat resistance and Hardened surface for stainless steel, cast iron, titanium, light-gauge metal and aluminum
- Surface-hardened Tip: The Cobalt drill bits for hardened steel penetrate tough, abrasive materials
- High-heat Resistant Bits: This drill bit set for metal withstands high-temperature applications for extended periods of time
- Thick Web-helix Design: The BOSCH drill bit set features a thick web-helix design that provides additional stability in tough applications
The Ultimate Buying Guide for Metal Cutting Drill Bits
Choosing the right drill bit for cutting metal makes a big difference. A good bit drills cleanly and lasts a long time. A poor bit breaks easily or burns out fast. This guide helps you pick the best metal cutting drill bits for your projects.
Key Features to Look For
Several features tell you how good a drill bit is. Pay attention to these points before you buy.
1. Point Geometry (The Tip Shape)
The tip shape controls how the bit starts drilling. Most good bits use a 118-degree or 135-degree point.
- 118-Degree Point: This is a general-purpose tip. It works well for softer metals like aluminum or mild steel.
- 135-Degree Split Point: This is better for harder metals. The split point helps the bit start drilling immediately without “walking” (skipping across the surface). This is a premium feature.
2. Flute Design
Flutes are the spiral grooves on the bit. Their job is to pull the metal chips out of the hole as you drill. Look for deep, well-formed flutes. Shallow flutes clog easily, which causes overheating.
3. Shank Type
The shank is the part that grips the drill chuck. Most common bits have a standard round shank. Ensure the shank matches your drill’s chuck size so it grips tightly. Loose bits spin and damage the hole.
Important Materials and Coatings
The material the bit is made from determines its hardness and heat resistance.
High-Speed Steel (HSS)
HSS is the standard for most metal bits. It is tough and handles moderate heat. It is a good, affordable choice for general work.
Cobalt (HSS-Co)
Cobalt bits contain 5% to 8% cobalt alloy. This material resists very high temperatures. Use Cobalt bits when drilling stainless steel or other tough, heat-resistant metals. They cost more but last much longer in hard use.
Coatings
Coatings reduce friction and increase durability. They are very important.
- Black Oxide: This coating resists rust and slightly lowers friction. It is better than bare HSS.
- Titanium Nitride (TiN): TiN gives bits a distinctive gold color. This coating is very hard and greatly reduces heat buildup. TiN bits offer excellent value for money.
Factors That Improve or Reduce Quality
Quality is about precision and heat management.
Improved Quality Factors:
- Precision Ground Edges: High-quality bits have very sharp, exact cutting edges. This means less force is needed to drill.
- Twist Rate: The rate at which the flutes twist affects chip removal. A proper twist rate keeps the bit cool.
Reduced Quality Factors:
- Cast or Milled Bits: Cheaper bits are often cast, not ground precisely. These bits dull quickly and vibrate when drilling.
- Soft Steel Core: If the metal underneath the coating is too soft, the bit will bend or break under pressure.
User Experience and Use Cases
How you use the bit changes what you need.
Light Duty/Home Use: If you only drill thin aluminum or soft steel occasionally, a good quality HSS bit with a Black Oxide coating is fine. Keep the speed low and use cutting oil.
Heavy Duty/Professional Use: For frequent drilling in thick mild steel or stainless steel, invest in Cobalt or TiN-coated bits. These handle the heat and stress much better. Always use appropriate speed settings (slower for harder metals).
Safety Note: Always use cutting fluid or oil when drilling metal. Oil lubricates the cut and carries heat away from the tip. This dramatically improves the life of any metal drill bit.
10 Frequently Asked Questions (FAQ) About Metal Cutting Drill Bits
Q: What is the difference between HSS and Cobalt bits?
A: HSS (High-Speed Steel) is standard and good for soft metals. Cobalt bits have added metal that makes them much harder and heat resistant, perfect for stainless steel.
Q: Should I use a slow or fast speed when drilling metal?
A: Always use a slower speed for metal than you would for wood. Fast speeds create too much heat, which quickly dulls the bit.
Q: What does the “split point” on a bit tip do?
A: The split point helps the bit bite into the metal right away. It stops the bit from sliding around on the surface when you start drilling.
Q: Why are my drill bits getting dull so fast?
A: Usually, the bit is getting too hot. You need to slow down your drilling speed or use cutting oil to cool the tip.
Q: Are gold-colored drill bits better?
A: Yes, the gold color usually means the bit has a Titanium Nitride (TiN) coating. This coating makes the bit harder and reduces friction.
Q: Can I use a metal drill bit on wood?
A: Yes, you can use a metal bit on wood, but it will drill slower and leave a rougher hole than a wood bit.
Q: What is the best drill bit size for general-purpose metal drilling?
A: A set of bits covering 1/8 inch to 1/2 inch is best. For single purchases, a 1/4-inch bit is very useful.
Q: How do I keep my new bits from rusting?
A: Always wipe them down after use. Store them in a dry place. Some bits come with a light oil coating that you should leave on until use.
Q: What happens if the drill bit chatters or vibrates?
A: Vibration means the bit is not cutting smoothly. Check that the bit is tightly secured in the chuck and that you are using the correct, slow speed.
Q: What kind of oil should I use when drilling metal?
A: Use a dedicated cutting oil or a heavy machine oil. Motor oil works in a pinch, but specialized cutting fluid works best to keep the bit cool and lubricated.