High Speed Steel Drill Bits – A Pro’S Guide To Choosing And Using Them

ByJim Boslice Metalworking & Fabrication

High speed steel drill bits are the gold standard for general-purpose DIY projects because they resist heat while cutting through wood, plastic, and mild steel.

To get the best performance, always match your drill speed to the material hardness and use a light coating of cutting oil when drilling into metal to extend the life of the bit.

If you have ever stared at a wall of drill bits in the hardware store, you know how overwhelming the options can be. You just want to make a hole in a piece of steel or wood, but you are faced with a dozen different coatings, lengths, and price points.

We have all been there, standing in the aisle wondering if the cheap set will actually work or if you are just throwing money away. The good news is that understanding your tools is the first step toward becoming a better craftsman.

In this guide, we are going to demystify high speed steel drill bits so you can stop guessing and start drilling with confidence. Whether you are building a workbench or fixing a bracket on your trailer, having the right cutter makes all the difference.

Understanding the Basics of High Speed Steel Drill Bits

At their core, high speed steel drill bits—often referred to as HSS—are engineered to maintain their hardness even when they get hot. When you drill into metal, the friction generates massive amounts of heat that would soften a standard carbon steel bit.

HSS is an alloy that includes tungsten, molybdenum, and chromium. These elements allow the metal to stay sharp and hold its edge under the intense stress of high-speed rotation.

Think of these bits as the workhorse of your workshop. They are versatile, affordable, and perfectly suited for the vast majority of tasks a home DIYer or garage tinkerer will ever face.

Why Material Selection Matters in Your Shop

Not all HSS bits are created equal, and knowing what you are buying prevents a lot of frustration. If you are working primarily with softwoods, you might not notice the difference, but the moment you touch stainless steel, that difference becomes obvious.

Standard HSS bits are bright and shiny. They are excellent for wood and aluminum, but they can dull quickly if you push them too hard into harder alloys.

If you are a regular metalworker, you should look for bits with a black oxide or cobalt coating. These are essentially HSS bits with a specialized finish that helps them dissipate heat faster and resist corrosion.

How to Use Your Drill Bits for Maximum Longevity

The biggest mistake beginners make is running their drill at full speed regardless of the material. This is a quick way to burn up your edges and ruin a perfectly good bit.

For larger holes in metal, slow is almost always better. High speed causes heat, and heat is the enemy of your cutting edge.

Use a center punch to create a small divot in your workpiece before you start drilling. This keeps your bit from “walking” or skating across the surface, which protects the tip from snapping on contact.

  • Use Cutting Oil: A tiny drop of oil on your metal surface acts as a coolant and lubricant.
  • Apply Steady Pressure: Let the bit do the work; if you have to lean your whole body weight into the drill, your bit is likely dull.
  • Clear the Chips: Periodically pull the bit out of the hole to clear away metal shavings, which prevents them from clogging the flutes.

Advanced Tips for Precision Metalwork

When you start working with thicker plates or tougher metals, the geometry of the tip becomes critical. A standard 118-degree point angle is great for general use, but it can be difficult to start on curved surfaces.

For those situations, consider a 135-degree “split point” bit. This design has a flatter tip that bites into the material immediately, preventing the bit from wandering.

If you find yourself snapping small bits, check your alignment. A handheld drill is harder to keep perfectly perpendicular than a drill press. If you are doing a lot of precision work, a drill press is the single best investment you can make for your shop.

Safety First: Protecting Yourself and Your Tools

Drilling, especially in metal, creates sharp, hot debris that can fly at high speeds. Always wear safety glasses, and keep your hands away from the point of contact.

If you are working with larger bits, be prepared for the drill to “grab” the material. If the bit catches, the torque can twist the drill—and your wrist—very quickly.

Keep your workspace clean and clear of loose clothing. A stray thread caught in a rotating drill bit can turn a fun project into an emergency room visit in a heartbeat.

Frequently Asked Questions About High Speed Steel Drill Bits

Can I use high speed steel drill bits for concrete or masonry?

No, you should avoid using standard HSS bits on concrete or stone. The abrasive nature of masonry will ruin the cutting edge of an HSS bit in seconds. Always use a carbide-tipped masonry bit for concrete, brick, or stone work.

How do I know when my drill bit is dull?

You will feel it immediately. A sharp bit pulls itself into the material; a dull bit will just sit on the surface and rub, creating smoke or a high-pitched squealing sound. If you are pushing hard and not making progress, it is time to sharpen or replace the bit.

What is the difference between HSS and Cobalt bits?

Cobalt bits are an upgrade over standard HSS. They contain a small percentage of cobalt, which allows them to handle much higher temperatures. Use them for stainless steel or other hardened materials that would otherwise ruin a standard HSS bit.

Should I sharpen my own bits?

If you have a bench grinder or a dedicated bit sharpener, absolutely. It is a great skill to learn. However, for very small bits, it is often more cost-effective to replace them, as the margin for error when sharpening by hand is very slim.

Mastering Your Craft Through Better Tool Habits

At the end of the day, your success as a DIYer comes down to how well you treat your tools. Investing in a quality set of high speed steel drill bits and learning how to maintain them will save you money and headaches for years to come.

Remember to keep your speeds low for metal, use plenty of oil, and keep your bits organized in a case rather than a jumbled coffee can. Your future projects will thank you.

Take the time to practice on some scrap material before jumping into your final piece. Once you get the feel for how the bit bites into the metal, you will be able to tackle even the most intimidating shop projects with ease. Happy building!

Jim Boslice
Latest posts by Jim Boslice (see all)

Similar Posts