The regular power drill is an incredibly versatile tool in such a small package, but when you’re faced with concrete and masonry, you need a more effective tool.
For serious drilling applications such as drilling holes into concrete, stone, block, and brick, there is one tool specifically designed for the job – the hammer drill.
The Hammer Drill Versus Regular Drills, Impact Drivers and Rotary Drills
All three of these tools look very much the same – pistol grip, trigger switch, and a drill bit on the chuck. It’s all too easy to confuse a hammer drill with a regular drill and an impact driver, or vice versa. To add to the confusion, there is the rotary hammer – another drill-like tool that has a hammer mode as well.
How A Hammer Drill Works: Hammer drills improve on the drilling and driving action of a drill bit by spinning two ridged discs against each other. Two thick, cam-like disks are ridged just like a ratcheted wheel with curved teeth, and one of them rapidly rises up and down against the other disk.
These quick hits add a hammering force on the chuck and let hammer drills put in even the longer fasteners into hardwood much more easily than an ordinary drill can. This pounding action also lets hammer drills bore regular holes quickly into masonry and concrete, as well.
Hammer Drill VS Standard Drills: Hammer drills, just like regular drills, can drill a hole into a concrete block with a masonry bit. The difference in their performance is night and day, though – sure, you can drill a hole with a regular drill with enough time and drill bits, but a hammer drill will do it much faster.
Your regular drill will burn out trying to drill into decade-old concrete while a hammer drill will put in hole after hole all day, thanks to the pounding force that makes them extremely efficient at blasting through masonry.
Hammer Drill And Impact Driver Differences: Just like hammer drills, impact drivers also have that same hammering action that helps the tool do its job. Unlike hammer drills, though, impact drivers are designed only for installing or removing nuts and bolts, while hammer drills are specifically designed for drilling holes. The impact driver can’t do the job of the hammer drill, and the same goes for the other way around, too.
Rotary Hammers And Hammer Drill Differences: Rotary drills have much more in common with hammer drills in this respect. They are both designed for drilling masonry, and both have the hammer action mechanism to do it.
The difference is that rotary drills, or rotary hammers as they are sometimes called, are much larger – some models begin to resemble smaller jackhammers in size. Rotary hammers usually have an SDS chuck, too, unlike the typical three-jaw chuck of hammer drills and regular drills.
Hammer drills and rotary hammers are, for practical purposes, variations of just about the same class of tools.
Choosing the Right Type of Hammer Drills
When it comes to hammer drills, two main types are commonly found on the market – hammer drills and rotary hammers. There’s a bit of overlap between hammer drills, and regular drills with a hammer function. Rotary hammers, on the other hand, can be considered as a drill specifically designed for drilling or hammering concrete and masonry, and little else.
Just like with most power tools, your options when it comes to hammer drills also come down to the corded electric type, or the cordless battery powered models.
In general, though, you want the most powerful hammer drill if you are taking on tough concrete and masonry. Bigger hammer drills, or even rotary hammers, will stand up to hard decade-old concrete all day even if you are using larger bits to drill larger holes.
In a typical job site, you can expect to drill a lot of holes indeed, and at a pace that will burn out even the toughest of regular drills. When it comes to hammer drills, bigger is often better, limited by your budget of course.
Light Duty Hammer Drills
Hammer drills in this range are more like regular drills with a hammer action, and these are your entry-level hammer drill models at a hundred dollars or less. Typically, you can spot a light duty hammer drill by their motor – most of them will have motors up to 6 to 8 amps if they are the corded electric type.
Many cordless hammer drills fall under this type as well, although the battery powered models are more expensive, of course.
With a light duty hammer drill, you can expect to drill holes up to half an inch wide into mortar and brick. They fall just a bit short of being able to deal with tough concrete, however, and you can expect to spend some time with each hole if you are using a light duty hammer drill on 50-year old concrete.
For woodworking and lighter masonry, though, these hammer drills are more than sufficient.
Heavy Duty Hammer Drills
In this range, you start to see motors ranging from 7 to 10 amps, and you can expect to take these tools against light masonry and concrete and do well in drilling holes up to 5/8 of an inch.
You also start to see more features with the more upscale models, as they start to offer multiple hammer and drill-only modes to make the tool more versatile for a variety of materials – masonry, wood, steel, and ceramic.
Features to Look For in Hammer Drills:
- A side assist handle helps you grip the tool with both hands for controlled, accurate drilling.
- A variable speed trigger lets you control the speed of the drill bit, letting you use the hammer drill not just on masonry and concrete but also for wood as well.
- A two-finger trigger will help in increased comfort and greater control.
- Solid metal gear housing for job site durability and increased reliability.
- Adjustable side handle with depth gauge lets you have greater control and versatility with the tool even in hard-to-reach spots.
- A carrying case is a big plus, especially if you are carrying a collection of bits with your tool.
- Built-in LED lighting lights up the target area, helping you see what you’re doing.
- Brushless EC motors are more efficient, run cooler and makes it possible to have certain smart features like soft start or kickback control.
- A hammering switch lets you turn off the hammer function, letting you use the hammer drill as an ordinary drill.
Cordless Versus Corded Hammer Drills
The big issue with electric corded hammer drills is that they need to be plugged into an outlet before you can use them. Once you overcome that little detail, you have unlimited operating time for as long as you need to get the job done – plus the electric motors that come with corded models tend to be on the bigger, beefier side too.
Hammer drills and rotary hammers are powerful tools and they can use up a lot of energy when you use them for their intended purpose – drilling through concrete and masonry. Having a corded hammer drill lets you keep on drilling without having to wait for a recharge, and these tools are usually safe enough to use with an extension cord, too.
Cordless hammer drills, on the other hand, are simply more handy on the job site, with no cord to get in the way. If you ever need to drill holes on a concrete or masonry ceiling or beam, the battery-operated models might just come in handy for you.
They are portable if you are working up on ladders or on scaffolding, and the better batteries that come with good brands can hold quite a good amount of charge – usually enough for more than 200 holes in concrete for a good 6 Ampere-hour (Ah) battery.
Rotary Hammer Drills
Rotary hammers are heavier and more expensive than ordinary drills. They are custom built for drilling holes into masonry, and they come with SDS chuck attachments for that. That said, they also come with hammer-only modes that let you use chisels and scrapers with the tool, which expands their range of uses somewhat.
The bigger rotary hammer drills models will typically come with hammer mode on all the time, as these are meant for the toughest jobs.
Features to Look For in Rotary Hammer Drills
- Vibration control features work with rubber mounting and foam padding to ease the stress on your hands, which is very important when working with this hefty tool all day long.
- Forward and reverse rotation modes let you back out of deep holes easier.
- Chisel function, also called combination hammer function, stops the bit from rotating. This lets you use a variety of attachments that work best with the hammering action, such as chisel bits, spade bits, or blunt nose bits.
- Kickback control automatically shuts down the motor in case the bit gets bound up in the substrate you’re drilling, preventing the tool from wrenching itself free of your grip. This can be a good or bad thing, depending on who you ask.
- Variable speed control lets you adjust the rotation speed of your rotary hammer, usually depending on how deep you press on the trigger. These work well with a lock switch in some models that let you maintain the current rotation speed.
- Soft start, or enhanced tool control, slowly ramp up the RPM of the rotary hammer so you can control the speed better, which is crucial when you are working with or next to delicate materials.
- Dust extraction reduces the amount of dust and debris ejected by pulling most of it in a built-in dust bag or out to a vacuum cleaner attachment port.
Comparing Hammer Drills
Power is the first criteria when comparing hammer drills – for dealing with tough masonry and concrete, every bit of power you can coax out of your tool will help you do the job faster.
After that, you also need to consider the size of the hole you need to drill – larger holes may call for larger bits, which means you have to choose between smaller 3-jaw chuck bits or the larger SDS bits.
Power and Impact Power
Like most, if not all, corded electric power tools, the power of the hammer drill is suggested by the rating of the main motor which is measured in Watts (W). Consider this as a rough guide to the power of the hammer drill – this input power rating translates into output power based on a variety of factors, from the gearing to the RPM of the tool.
Corded rotary hammers are also rated in terms of Amps (A), while cordless rotary hammers have voltage (V) ratings. For battery-operated models, running time can be estimated from the battery capacity rating, usually given in Ampere-hours (Ah).
As a tool with an impact piston hammer, rotary hammers have impact energy ratings. Impact energy, in this case, is given in Joules (J) – the higher the figure, the harder the piston can slam into the chuck.
Speed and Hammering Speed
Rated speed is usually given in rotations per minute (RPM). Hammer drills spin at just about the same speed as regular drills, and they can reach up to 3,500 RPM. Rotary hammers drills, on the other hand, often go slower – typical models usually spin in the sub-1,500 RPM or slower.
It’s the same story when it comes to hammering speed. Hammering speed is given as an impact rate in terms of beats per minute (bpm), and typical rotary hammer drills can have impact rates up to 4,000 bpm or more. Hammer drills, on the other hand, have much faster bpm rates – expect bpm ratings of 50,000 bpm or more from your mid-range hammer drill.
Drilling Depth
This is one of the most important considerations you will need to look at when buying a drill, whether it’s a regular drill, hammer drill, or a rotary hammer, and manufacturers will usually give out detailed estimates of the drilling range of their tools.
Drilling ranges are usually specified in millimeters (mm) for metric scales, or inches (in.) for imperial. Maximum drilling diameters are usually provided for masonry, wood, and metal in the case of hammer drills.
