Powder-actuated stud drivers are actuated by pulling on a trigger or by tapping lightly with a hammer on an exposed firing pin at the top. The better quality models have built-in safety features which prevent accidental discharge when the base is not in contact with the concrete. However, caution and careful attention to handling instructions are still required when handling them. Most are large, heavy-duty models which are quite expensive, though they can be rented from tool rental agencies in many communities.
Far more popular with do-it-yourselfers, and much lower in price, is the newer, hammer-in type of stud driver. These are hand-actuated. That is, power is delivered by striking with a hammer on an anvil or head at the top. Using the same principle as the powder-actuated models, these hammer-in tools hold the nail or stud in a tight-fitting tube or sleeve. An anvil in the other end of this sleeve projects at the top so that it can be struck with a hammer to force the nail or stud into the masonry when the base of the driver is held snug against the surface. Nail-type fasteners or drive pins up to 3 inches in length can be used, or they will accept threaded studs up to 2 inches in length.
The threaded studs have a nail-like point which is driven into the surface so that the threaded end is left projecting. Nuts can then be screwed on over the threaded end to hold angle brackets or similar fixtures in place. For best results, a heavy hammer weighing at least 21/2 pounds should be used. Lighter hammers set up excessive vibration, making it difficult to deliver the necessary power with accuracy.
When strips of lumber are to be nailed against the wall, the nail-type fasteners are usually used. These can be driven directly through the lumber into the concrete. However, it is important that the lumber be held tight against the surface while nailing, and washers which are specially designed to fit onto the nailhead should be used. These washers serve two functions: they help guide the fastener while it is being driven home, and they help create a better grip after the piece has been nailed into place.