It used to be easy – just drill and that's it. However, now we have impact drivers that give us more options than we usually know. Many people have asked us recently what is the difference between an impact driver and a drill? How and when you use your impact driver vs drill actually matters. Then, there is the issue of using an impact driver versus an impact drill. This leads to more problems. Before diving in, understand that these tools have different mechanisms to get the job done. They also like different apps. Proper use of each tool yields maximum efficiency – which is why you often see professionals carry more than one tool.
As a more advanced tool user, we can provide you with basic answers as well as some in-depth insights. This can be helpful if you're wondering whether you should buy a two-tool combo kit or stick with a basic drill. Seeing how manufacturers make these tools and how they differ should help you decide for yourself which ones you need.
At the very least , we can help you sound like you know what you're talking about when the next tool deal hits Acme Tools, Home Depot, or Lowe's!
It's simple, the drill rotates the chuck on the front of the drill. Most chucks are now keyless, which means you don't need that funny-looking key bent at 90 degrees to change bits. To use a keyless drill chuck, simply grab it and unscrew it one way and tighten it the other way. The ratchet chuck is exceptionally strong and will grip almost any shape that fits it, including smooth drill bits.
Many drills have multiple speed and torque settings. The exact use of these can be left for a later discussion, as we only want to understand the main differences for now.
Impact drivers work similarly to a power drill in that they rotate the bit you attach it to. When using a drill to drive large fasteners, you may run into situations where you cannot continue to drill. It uses all the power and torque, but just can't move large fasteners or bolts. This is where an impact driver comes in.
They provide more torque.
Impact Drivers When You Need More Torque
Imagine working on a bolt that is difficult to loosen with a wrench. You lean on it and pull on it – but you still can't move it. To knock it loose, you finally decide to grab a hammer and hit the handle of the wrench. This provides an extra but brief burst of torque.
That's what impact drivers do. But it can execute thousands of times per minute.
When it gets to the point of jamming, the mechanism inside automatically starts "slamming" the chuck to continue driving the screw or tightening/loosening the bolt.
An impact driver is much stronger than a drill because it can provide extra torque to loosen stuck bolts and screws or drive them deeper into the material.
Drills Deliver Faster Speeds to Fasteners…but at a Cost
As the impact driver mechanism repeats the cycle of the anvil driving the chuck to rotate, it loses efficiency. The drill applies constant force to the chuck, driving the fastener without stopping or pulsating. As a result, impact drivers tend to drive fasteners more slowly while giving you more torque.
We've seen this over and over again in our drill vs impact head-to-head comparisons. A capable drill will drive in sorted screws faster than an impact driver every time…almost. Exceptions arise when the required torque exceeds the power of the drill to maintain its optimal speed. When this happens, the drill slows down while the impact driver continues to drive the fastener into the material.
Impact Drivers & Drill Chucks
Impact drivers use 1/4" quick-lock hex chucks. These allow you to insert a hex bit, and some automatically lock the bit in place. Other smaller designs require you to pull out the flange to insert the bit. To remove it, You pull the collet out again and it releases the bit.
One advantage of this system is that it comes in a more compact design, which helps you get into tighter spaces. The downside is that it requires one hexadecimal digit. Your round drill bits will not fit these impact driver hex chucks.
Until recently, if you wanted to drill a hole, you had to use a drill. Companies such as Milwaukee, Ridgid, and DeWalt now offer drill bits for impact drivers. There is a push in the industry to allow you to use an impact driver to do everything a drill can do. Be careful though! Impact drivers have much more torque than drill bits, and some applications recommend an impact-rated drill bit, not just the standard bit that came with the big $19.99 kit at Christmas.
Many impact drivers on the market are single speed. However, as more accessories are being manufactured to include more drilling capabilities, some companies are offering impact drivers with multiple speed and torque settings.
How about a rotary hammer?
Hammer drills start with a traditional drilling action and have the same type of chuck as a drill. In fact, most allow you to switch between drill and hammer drill modes. Like a drill, a hammer can have multiple speeds. Instead of making the striking action work in the same direction as the chuck rotates like an impact driver does, a hammer drill "hits" the bit forward by rotating it, the way a hammer transmits force. Imagine using a drill and hitting the back of it quickly with a hammer as you go.
Rotary hammers tend to work best when working on concrete, masonry, stone, and other similar materials. There really isn't any benefit to using a hammering action to hammer into wood or drywall. In fact, the hammering action tends to damage those softer materials. All percussion drills work with the hammer mechanism turned off when drilling into material that does not require it.
When to use a drill, impact driver, or hammer drill…it's easy for me!
When to Use a Drill
- Driving screws into wood, drywall and other soft materials
- Tightening/loosening bolts that do not require extreme torque
- Drill holes in wood, drywall and other soft materials
When to Use an Impact Driver
- Drive screws into wood or metal (you can use this for drywall if you have the lower speed/torque option)
- Driving Large Diameter Screws or Lag Bolts
- Tighten/loosen bolts, including those that should be tight or have seized
- Drill holes in wood, drywall or metal with new impact driver designed bits
When to Use a Hammer Drill
- Drill holes in concrete, masonry or stone (in hammer drill mode)
- Driving screws into wood, drywall and other soft materials (drill mode only)
- Tighten/loosen bolts (drill mode only)
- Drill holes in wood, drywall and other soft materials (drill mode only)
Should I buy a power drill, impact driver, or hammer drill?
That's a tough question to answer because there are so many different needs out there. If you're only going to buy one product, I'd go with the impact driver. The new drill lets you do everything you can with a traditional drill. You're just missing out on the hammering action that optimizes drilling in concrete or masonry materials.
If you can afford a two-tool kit and know (or think) that you might need to drill holes in concrete or stone, use an impact driver/hammer drill kit. Even without a special bit, the hammer drill should have a drill only mode that lets it work like a drill, and then you'll also have the impact driver for when you need more torque with nuts/bolts and lag bolts. If you're not going to use these masonry applications, stick to a drill/impact driver kit.
Impact drivers and drills in action
I've had the opportunity to use these tools on several recent projects. For example, we helped a local church build a wheelchair ramp. For drilling the pilot holes and driving the screws we only need a drill bit. So for projects like building a deck or putting up a wooden fence, a power drill is a good choice.
We had to anchor the ramp to the concrete at the end, so we used a hammer drill to make the holes, which we then used to drive the Tapcons into place. An impact drill is the best tool when you need to drill a smaller hole in concrete. Large holes are usually done with a tool called a rotary hammer.
Surprisingly, the impact driver actually does a good job of making smaller holes in concrete when using a multi-purpose bit. I would limit their use to holes smaller than 3/8" in diameter.
I recently assembled a grill and used my impact driver to make sure each connection was very tight. Mechanics will often use an impact driver to tighten and loosen bolts on the engine. Many gas engine machines, such as lawn mowers and trimmers, require the use of an impact driver (or impact wrench) to properly tighten and loosen bolts. Anytime you use a bolt on metal or drive a screw into metal, you need an impact tool.
our personal preferences
An impact driver is my tool of choice in most cases. I personally keep an impact drill/impact driver kit on hand for all my drilling and driving needs.
Do you still have questions? Ask us! We love helping others learn about our favorite tools and how to best use them!
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