Best Drill Bits for Hardened Steel Reviews 2018

DEWALT Discounts

What makes the best and top rated drill bits for hardened steel? If you have ever attempted drilling through hardened steel, or metal, then you know just how tough that can be.

Using an ordinary drill bit designed for normal metal materials will not work, and in fact will ruin that bit for other uses.

The perfect drill for taking on hardened steel is a “Cobalt HSS” drill bit which has been specifically designed for this purpose.

Understanding Hardened Steel

I always find that when I understand how something is made, that it is easier to understand how you can work with it. This includes how to drill it. Hardened steel will take an ordinary steel that is high in carbon content and put it through the processes of quenching and then tempering.

To harden steel extremely high temperatures are used, and that type of steel must have a lot of carbon in it to begin with.

All hardened steels go through a four step process which I will not bore you with here. It is important to note that the carbon steel is heated to high temperatures which hardens the steel.

It is then dipped into cold water, pretty much in the way you would see a blacksmith working, but that makes it brittle.

The tempering process then reduces how brittle the steel becomes and the net result is you are left with a pretty tough steel product.

I have included a video below on how to check if the steel you are going to be drilling is actually made from hardened steel.

Video On How To Check If Steel Is Hardened or Not

Uses of Hardened Steel

Hardened steel is used for objects that are subject to high levels of force or abuse such as cranes, car parts, trucks, hand tools, guns, and knives to name but a few. Compared to ordinary steel, hardened steel is much more durable, more resistant to wear and tear and perfect material for all types of heavy duty applications.

Top 3 Drill Bits For Hardened Steel

So at least we now know what we are trying to drill through. If you have never done this before, then you are in for a pretty tough piece of drilling. Attempting to do this with any of the standard drill bits that you get will be impossible.

If you try to use any of those, then not only will you be wasting your time, but the hardened steel will ruin those bits for use on other types of softer metals.

You need a drill bit that has been designed to cut its way through the hardened steel and a cobalt drill is the correct type. I have listed below the best 3 cobalt drill bits available on the market today. Just before you have a look at them I think it is important to understand how HSS drill bits are actually graded.

Cobalt Drill Bits

There are basically 5 different levels of HSS drill bits

  • T1
  • M2
  • M7
  • M35 – 5% cobalt
  • M42 – 8% cobalt

So for drilling through hardened steel you would want bits with an M42 rating

DEWALT DW1361 Titanium Pilot Point Drill Bit Set for Steel

DEWALT DW1361 Titanium Pilot Point Drill Bit SetThe logic is that to drill through any material the drill bit that you are using has to be made of a material that is harder, than the material you are trying to drill through.

In addition to this, very high temperatures will be created when you perform any kind of drilling task. With the Dewalt DW1361 set, you get 21 high quality drills, at a very affordable price.

This set includes sizes from 1/16-inch to 1/2-inch and they come in a tough plastic case, which will help keep them safely stored. Just remember these need to be used in a Jacob’s style chuck.

They have a titanium pilot point which ensures a much longer life for each of your bits.

You Can Check Out Their Availability Over at Amazon by Clicking Here

Neiko Super-Hard 13 Pcs Cobalt Drill Bit Set for Steel

Neiko 10178A Cobalt-coated Steel Drill Bit SetMy second choice are considerably cheaper and yet these will also handle hardened steel. You get 13 drill bits here instead of the 18 in the Bosch set above. These also come in a nice looking metal box.

In my opinion these are not the same high quality as the Bosch ones above and I think that is reflected in the price. At the end of the day these are under $10 and will get the job done for you.

They are in my opinion though only suited for that. So if you are someone who will be using drill bits a lot, better to spend the extra money and get a really good set.

I have simply included these because of the price but they contain very low amounts of cobalt so will not last that long. They are ideal for a small job or infrequent use.

You Can Check Their Availability over at Amazon by Clicking Here

Irwin Industrial Tools 63221 Cobalt Metal Index Drill Bit Set, 21-Piece for Hardened Steel

Irwin Industrial Tools 63221 Cobalt Fractional Straight Shank Jobber Length Metal Index Drill Bit SetIf you can afford these cobalt drills then these will last you for a very long time. These are very high quality and will last a long time. Buying cheap drill bits is never a good idea in my honest opinion.

I have done that in the past and the reality is that after a few uses you may as well throw them away as they become blunt and useless for drilling.

I think you are better with one good set that you can reply on to get the job done. The problem is of course you will have to pay to get that type of quality.

I guess therefore it depends on how much use they are going to get and how much you really need or depend on them.

This set gives you 21 high quality cobalt bits and are M42 rated with a 5% cobalt content.

You Can Check Out Their Availability over at Amazon by Clicking Here

That concludes our reviews, on what we believe to be the best drill bits for hardened steel. Hopefully you found it helpful.

Enda McLarnon

Enda McLarnon is now retired and is now enjoying writing about his love of power tools. All types of these tools are now available and they make working on projects and DIY jobs around the home a great deal of fun