Screwdrivers are among the most basic hand tools whose sole purpose is to drive screws. Standard screwdrivers are composed of three major parts: tip, shank (together they are the blade) and handle. There are a variety of handles including the traditional plastic handle, ergonomically designed handles and ESD (Electrostatic Dissipative) safe handles. Insulated, anti-spark and electronics screwdrivers are also available. Screwdrivers are classified according to tip type, blade width and length.
Used for fasteners in the manufacture of mobile homes and truck trailers. Also referred to as a butterfly bit.
Tip designed to turn socket head fasteners.
Cross point tip designed to minimize slippage. The operator can apply more torque and hold tighter than a slotted tip.
Similar to Phillips® but ground at a different angle to allow for a greater application of pressure. Pozidriv® has four "grip" lines pointing out from the center. They are not designed to be used on Phillips® head screws, as they will damage the head or the tip.
Square Drive (also known as Robertson®):
A square-tip screwdriver, designed for maximum torque. Generally used for recessed screws in practical production projects such as recreational decks and furniture.
Blade usually tapers to a flattened tip. The slotted design cannot maintain a consistent grip under power and may often slip or cause damage (1⁄8 - 7⁄32" diameter are commonly referred to as Cabinet Tip).
Similar to Torx, but the drive socket has a projection to prevent a standard Torx driver from being inserted.
For tamperproof screws, used to restrict access. Also referred to as a security tip or Snake Eyes® Spanner.
Special cross tip design. Widespread use in the aviation industry.
Profile delivers more torque and longer tool life than conventional Torx profiles. Torx tools can drive Torx Plus fasteners, but not vice versa.
The asymmetrical arrangement of the profile flanks prevents the use of any incorrect tools. Mostly found in household appliances and aviation engineering.
Caution: Insert and power bits are not to be used with impact power tools.Selecting the Proper Screwdriver
- Always select the screwdriver that best fits the screw head; the tip must fit the slot securely with no overhang on either side. If the fit is wrong, the screwdriver could slip and damage itself, the screw and/or the work as well as cause injury to the user.
- How the handle fits your hand determines the amount of torque and pressure that can be applied. Handles are generally made of plastic and should be shaped to provide a comfortable grip. As another safety tip, always make sure the handle is clean and not greased to prevent slipping and injury.
All too often screwdrivers are misused for prying, scraping, chiseling and punching (among other things) which frequently results in chewed up screw heads, damaged screwdrivers and injured hands.