All About Screwdrivers

Screwdrivers are usually classified as flat head or cross-headed. Cross-headed screwdrivers have cross-shaped tips. Take care to use the correct type, since a mismatch may damage the head of the screw or the screwdriver.
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©2007 Dorling Kindersley Limited

©2007 Dorling Kindersley Limited

©2007 Dorling Kindersley Limited

Photo By: DK - Do It Yourself Home Improvement ©2009 Dorling Kindersley Limited

Photo By: DK - Do It Yourself Home Improvement ©2009 Dorling Kindersley Limited

Photo By: DK - Do It Yourself Home Improvement ©2009 Dorling Kindersley Limited

Photo By: DK - Do It Yourself Home Improvement ©2009 Dorling Kindersley Limited

Photo By: DK - Do It Yourself Home Improvement ©2009 Dorling Kindersley Limited

Photo By: DK - Do It Yourself Home Improvement ©2009 Dorling Kindersley Limited

Flat-Head Screwdriver

The shaft has a flattened, often tapering head and a straight tip that fits into the head of a slotted screw. Flared tips are common on flat-head screwdrivers. The flare makes the tip stronger so it allows you to apply extra torque. By contrast, parallel tips align with the width or diameter of the shaft. This is important when a screw needs to be driven in below surface – the edges of a flared tip would wedge in the hole.

Phillips Screwdriver

With a cross-shaped head, the tip may be pointed or flattened. Small ones tend to be pointed; larger ones are often flat.

Pozidriv Screwdriver

These are similar to the Phillips, except that between each cross-projection is a smaller projection that provides greater grip. The pozidriv cross-headed tips allow the screwdriver to fit into the head of a screw more securely than a flat-head tip, enabling you to apply greater rotational force.

Using a Screwdriver

Be sure to select an appropriate screwdriver to match the size and type of screw. Hold the screwdriver at right angles to the screw head, then ensure that the tip of the screwdriver is fully inserted into the head of the screw before turning it. Turn the screw clockwise to tighten it and counterclockwise to loosen it. Depending on the length of the screw, it may be necessary to adjust your grip several times. To insert a wood screw without damaging the wood, first you may need to drill a pilot hole.

Stubby Screwdriver

As the name suggests, this screwdriver is very short and is designed for use in areas that a regular screwdriver will not fit into.

Jeweler's Screwdriver

This type of very fine screwdriver is designed for particularly intricate tasks. To use it, apply pressure to the revolving head with your index finger, and use your other fingers and thumb on the middle section of the handle to turn the shaft.

Electric Screwdriver

An electric screwdriver can make working with screws much quicker. It is usually powered by a rechargeable battery and comes with a selection of interchangeable bits that fit into the neck of the shaft. In this model, a central switch sets clockwise or counter-clockwise rotation, and a button next to the handle activates the shaft's turning mechanism. In many ways, cordless drill-drivers have taken over from the simple electric screwdriver shown here. However, these still have a function for lightweight work.

Ratchet Screwdriver

You can use a ratchet screwdriver to drive in or take out a screw without having to readjust your grip. A three-position switch selects different functions. With the switch in the central position, the screwdriver operates like any other. With the switch to one side, the handle will rotate in one direction but lock when turned the opposite way. This enables you to simply rotate the handle one way and then the other to screw in or unscrew a fastener. Some ratchet screwdrivers have a spiral action in the shaft that turns the bit as you apply downward pressure.

The Screwdriver Handle

Traditionally, screwdriver handles have a bulbous section designed to fit comfortably in the palm of the hand. Modern designs place emphasis on a soft grip with a bulbous but less exaggerated section. Fluted handles are much thinner, and the fluted section along the handle shaft provides better finger control of the screwdriver.