A hammer drill and an impact driver are used for similar purposes. If you have to drill in a screw, a nail or any hard object that must be installed in a given surface or block of material, you would either resort to a hammer drill or an impact driver. While the two are very similar in what they do, there is substantial difference between hammer drill and impact driver, pertaining to the way they work and how efficient they are.
Difference Between Hammer Drill and Impact Driver
The most observable difference between hammer drill and impact driver is the manner in which they apply the force onto the bit being drilled. A hammer drill works in a very simple manner. It exerts a direct force on the bit. Imagine that you have a nail or a screw and you have a hammer. Just the way you would hammer the nail into the object, a hammer drill would be directly exerting the force on the bit to drill it hard into the surface. Of course, you can use varying degrees of pressure or force. But you cannot do much about the direction of the force.
In contrast, an impact driver exerts a force perpendicular to the direction in which the nail or screw is being drilled in. The bit is not subjected to direct pressure. As you operate an impact driver, the rotation is facilitated by a further force that is at a right angle, which makes the drilling smoother and less impactful on the bit or the surface.
A hammer drill will feel like a jackhammer. An impact driver would be much more subtle. An impact driver uses two rotation mechanisms to exert the perpendicular force. Remember, it is the additional force that complements the typical drilling force. To cater to the varying rotational mechanisms, an impact driver has three special components, those that you wouldn’t find in a hammer drill. The components are a t-shaped anvil, weight or what is also known as impact pass and a strong compression spring.
As you begin to operate an impact driver, the tool generates the same speed for the spring and the bit being drilled. As you keep increasing the resistance, the rotation of the bit slows down and the difference in the speed of the bit or the weight and the spring or the motor will account for the additional force applied perpendicularly.
