Cordless screwdrivers use rechargeable batteries instead of an electrical cord to power a strong reversible motor attached to a shaft. They feature a number of interchangeable bits, including flat blade, Philips head and socket attachments. Do-it-yourselfers and crafters often use these tools to prevent hand exhaustion and create more torque (twisting power)than standard screwdrivers.
Torque is an important factor when using cordless screwdrivers, perhaps even more than speed. A typical screw must penetrate many layers of wood fiber or burrow through hard material in order to become an anchor. This requires substantial twisting strength, which fully charged cordless screwdrivers should have in abundance. Most also allow the user to tighten screws manually and only use the added torque when necessary.
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Another important feature of these tools is reversibility. During deconstruction work, some screws may become damaged or rusty. Generating enough torque to manually remove these screws may prove impossible, but cordless screwdrivers can often overcome the initial resistance and guide the screw out of the material. A two-way switch on the grip of the screwdriver determines which direction the motor will turn.
People can also avoid problems of repetitive motion by using this tool. Turning an endless series of screws in a large project can put undue stress on the crafter's hand and arm muscles. Cordless screwdrivers could be mounted above the workstation and brought down to tighten screws or drill holes repeatedly. Some workers using manual screwdrivers also injure themselves through constant bumping and scraping in awkward workspaces. If a cordless screwdriver can safely reach the location of a screw, it can generate enough power to drive it home without an awkward hand position. Some also feature flexible extenders which can reach tight spaces and still turn screws effectively.
Cordless screwdrivers and accessories make good gifts for woodworkers, crafters and those who enjoy do-it-yourself home repair projects. Some cheaper sets do not provide sufficient torque for heavy duty projects or enough battery life between charges. Examine the screwdriver bits for quality construction and material — cheaper bits can break off unexpectedly during use. Above all else, never force a cordless screwdriver to exceed its limits. If a screw refuses to budge, find another method of removal or work around it.