Professional mechanics depend on air tools, especially a pneumatic impact wrench to get their work done. When working on stubborn nuts and bolts, an impact wrench can quickly loosen what would otherwise require massive amounts of sweat (and probably a few busted knuckles along the way). The only drawback with pneumatic impact wrenches is you need a pretty good sized air compressor to power them.
For the rest of us, there are hand impact drivers. These wonderful and inexpensive tools allow you to take hammer force and convert it to rotational force. Attach a socket or bit, and you can suddenly loosen that stubborn fastener. Not only that, but since you are applying the hammer to the back of the tool, you are insuring that the bit or socket doesn’t come off the fastener.
One added advantage of using a hand impact driver is the frustration relief provided by being able to hit the fastener that’s giving you so much trouble. It's going to take a good whack to break it loose, so you'll be able to take out all your aggression and frustration on it, rather than slamming the door and kicking the cat. That makes it an all-around better alternative.
Because these tools take a lot of abuse, quality is important. While a fairly simple device, if the metal is too thin or not properly tempered, it can break rather easily. Of course, how often you have to use it becomes a factor as well.
The most common size for these sets is with a 3/8 inch drive. There are a few out there designed for a 1/2 inch drive, but they're not common. Make sure that you use impact sockets with them, if you need to use a socket. Impact sockets have thicker walls and aren't chrome plated, so they're much less likely to break from the force of the blow.
If you're looking for quality, you need to stick to the top tool brands. This is one area where you definitely get what you pay for. I picked this kit from Proto, because they manufacture professional grade tools. While more expensive, it's also better quality. Read Full Review
I picked Proto's set as number one mostly based upon their quality. This is a company that manufactures tools for the professional; maybe not in the same league as Snap-on, but definitely as high as Armstrong and Mac. This is a 3/8 inch drive impact driver; which comes with two different sizes of hex adapters and 10 bits. As best I can tell, they're the only manufacturer that gives you two different sizes of hex adapters. Everything comes in a plastic case for ease of storage and to prevent loss. The impact has a heavy-duty spring for added torque.
I really like the flange on this tool, which protects your hand from accidental misses. The 3/8 inch size is useful for most individuals, because they don't have 1/2 inch drive sockets. Read Full Review
OTC is a well known and respected supplier of specialty automotive tools. One of the great things about this tool is the handle, which is cushioned for good grip, but also includes a flange to protect your hand. If you’ve ever tried to use one of these without the protector, or even a chisel without a protector, and gotten your hand with the hammer, you’ll understand the importance of this option.
This set comes in both 3/8 inch and 1/2 inch drive. I picked the 3/8 inch drive over the 1/2 inch drive simply because most people have 3/8 inch drive sockets, even though many don’t have 1/2 inch drive tools. This kit comes complete with several bits to accommodate most standard screw sizes.
Once again, we've got a tool with hand protection. Considering the force you've got to strike a hand impact with. I'd never consider using one without that flange. Read Full Review
SGs unit is almost identical to the OTC unit mentioned above, with all the same options and benefits I’ve mentioned. I especially like the comfort-grip protective handle. The soft grip helps you hang onto the tool and the flange protects your hand from those inadvertent misses. To me, that sets these tools apart.
This is also a 3/8 inch drive unit, allowing you to use standard sockets or the included bits. It comes with eight bits; four shorties and four extended reach ones. The nosepiece on the driver is an adapter, hiding the square drive head.
Although there's no comfort-grip safety handle, this unit is knurled, making it easy to hang on to, especially with greasy hands. Removing that handle also makes it easy to keep clean. Read Full Review
Although this unit doesn’t come with the comfort-grip safety handle of the previously mentioned units, the knurled bands on the body make it easy to hang on to. Even though I prefer having that hand protection, it can get in the way, especially if you're trying to use the tool in tight spaces. It’s also easier to keep clean than those with a plastic band. Lisle provides their kit in a nice plastic case, to help insure everything stays together. I don’t know about you, but personally I like kits that come with a case.
For simplicity, try the K-D Tools hand impact. Nothing fancy about this unit, but then, there's nothing fancy about the price, either. Read Full Review
For those that are seeking simplicity, KD Tools provides a basic hand impact driver. There’s nothing fancy about this unit, but there’s nothing fancy about the price either. It comes with the adapter and bits, just like the more expensive units; and works the same way. This is a 3.8 inch drive unit, so it will fit all your standard and metric sockets. A good pick for those who don’t have to use it very often.