Rotary Hammer Vs Hammer Drill

As a DIYer or a professional, at one point or the other, you are likely going to deal with harder materials, including concrete. To fulfil your purpose, you will require a masonry bit along with a regular drill. However, knowing the differences between a rotary hammer vs hammer drill could help you decide which one you should according to the material you’re going to work with.

A rotary hammer and a hammer drill are two tools that are designed for the same purpose but have slight variations in terms of how they function, their impact, bits, the scale of usage, and more.

In this guide, we will break down everything that you need to be aware of regarding the comparison between these two tools.

So, without further ado, let’s get started!

What is a Rotary Hammer

Rotary Hammer Vs Hammer Drill

A rotary hammer performs numerous actions simultaneously to function. Not only does it use a piston system and air pressure to drive the bit forward into the material you are dealing with, but it also turns the bit like a drill.

Coming to the bits that we use with a rotary hammer, they are either SDS-Max or SDS-Plus. These bits easily get fixed into the rotary hammer chuck and do not require any tool or chuck key for either insertion or removal.

Another less commonly used bits for a rotary hammer, that have also become somewhat conventional, are spline bits.

Apart from bits, a rotary hammer is often equipped with a few popular attachments to adjust to the material we are dealing with. These include:

  • Cold chisel: To bust up concrete.
  • Clay spade: To break up hard soil.
  • Tile remover: Pulls up ceramic tiles.
  • Scaling chisel: Removes weld spatter, concrete, and rust.
  • Bull point chisel: initiates holes in concrete.  

A rotary hammer is much larger in size than a hammer drill. However, unlike the latter, you can never use it to drive fasteners.

How Does a Rotary Hammer Work

Rotary Hammer

With strong internal parts, a rotary hammer uses a drive piston to apply air pressure to a flying piston. As a result, the bit drives forward while the electric motor spins it rotationally as well. In the best variants of the tool, there is even better performance due to the use of advanced timing for the synchronization of impacts and rotation.

In addition to this, there are a variety of modes in a rotary hammer. The majority has a rotary-only mode, that does not offer the hammering piston action. On the other hand, other variants of the rotary hammer also possess a hammer-only mode, that practically makes them small chipping tools.

Hence, you can use them to remove small amounts of stone, brick, block, or tile, etc.

What is a Hammer Drill

A hammer drill, as its name suggests, is a type of drill. The only thing that separates it from traditional drills, is its hammering action.

It produces a pounding force, right behind the bit, which allows it to drill into masonry material.

How Does a Hammer Drill Work

Drill

A hammer drill uses a pair of impact gears, that are fit together, such that when the bit rotates in hammering mode, these gears produce a vibration against each other.

The vibration produced is transferred to the bit, along its axis, through the motion of the chuck. As a result, the drill rotates and hammers into the material while it drills and hence, the effect of the hammer drill, when equipped with a masonry bit, is drastically enhanced.

It is worth mentioning that by design, a hammer drill does not go into the material until you press it. There is a set of springs that separate the two rigid discs on the hammer. When you push the bit into the concrete, these discs come together and the hammer mode is activated.

If you want to use your hammer drill for woodworking or fastening jobs, you can put it into drill-only mode by pressing a switch, on it, specifically made for the said purpose.

Impact

When it comes to the impact generated by the two tools under consideration, a rotary hammer seems to have the edge due to its much greater force. This is because it physically forces the bit inside the material via the flying piston.

On the contrary, in the case of a hammer drill, the amount of force generated depends upon how firmly the user presses onto the tool.

While the hammer drill loosens up a hard material, such as concrete, by vibrating against it, the rotary hammer chips away at the same materials as it drills.

Maximum Hole Sizes

Hammer Drilling

While the hammer drills reach their limit at holes of around ½-inch in diameter, a rotary hammer can drill holes of up to 2 inches in diameter. Furthermore, with the same-sized bit and a smaller hole, a rotary hammer drills much more quickly as compared to the hammer drill.

Hammer drills are basically, not suited to drilling lots of holes. On the other hand, rotary hammers are not only relatively affordable, but they can also adjust to just about any size of hole you want to drill.

As a general rule of thumb, for holes starting from 1/8 inches, up to ¼ inches, a hammer drill will get the job done for you. However, if you are looking to drill loads of holes and that too, over ¼ inches, you should really consider the speed as well as the versatility of a rotary hammer.

Though the rotary hammers are comparatively weighty, their added weight is completely neutralized by their impressive speed.

Large-Scale or Small-Scale Jobs

When it comes to a small-scale job, such as drilling a handful of holes of a specific diameter, a smaller hammer drill works great. However, for holes larger than 3/8 inches in diameter, whether you need to drill them in masonry, concrete, or rebar, a rotary hammer is your go-to choice.

This does not, however, mean that a rotary hammer is used relatively more than its hammer drill counterpart. It is more versatile in terms of how it can be used; apart from masonry, it can be used on wood as well. On top of that, it can tackle holes of ¼ inches or smaller for periodic Tapcon Installation.

On the other hand, a rotary hammer is used for only drilling in concrete and possibly functions as a chiselling tool.

Bits

The bits used for rotary hammers have a greater concentration of carbide as well as a sharper flute pattern for quicker chip removal.

As for the hammer drill bits, they resemble regular bits, having a small carbide tip. They also come with the added benefit of supporting a thicker core with shallower flutes.

Frequently Asked Questions

Hammer Drill

What is the Difference Between Rotary Hammer Drill and Impact Drill?

As opposed to the rotary hammer, an impact drill requires a great amount of force when drilling into hard materials. The impact and noise level, in turn, are also much greater, in comparison.

Can You Use Hammer Drill as a Normal Drill?

Yes, as mentioned above, by putting the hammer drill in the “drill” mode. Remember, however, that it has some limitations.

Can you Use a Hammer Drill to Remove Lug Nuts?

No, you can’t remove lug nuts using a hammer drill. You will require an Impact wrench for the job.

Conclusion

Well, there you have it – a comprehensive guide on the differences between a rotary hammer and a hammer drill.

To reiterate, a rotary hammer is more impactful, affordable, can drill holes of larger diameters, and is primarily used for large-scale jobs. On the other hand, a hammer drill is more versatile in terms of the types of materials it can be used on.

Liam Weissman

Hello and welcome to PowerToolGenius! My name is Liam and for the last 9 years, I have worked extensively with various power tools and accessories. I have tested hundreds of different brands and models and understand the industry extensively and have been working with tools my entire life!

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