Hand Tools and Their Uses

Striking Tools, Punches, and Chisels

Striking tools deliver impact force to drive fasteners, shape materials, or seat components. A standard claw hammer features a flat striking face designed for driving nails and a split claw, which is often curved, to grip and pull nails from wood. In metalworking, a ball-peen hammer is selected instead; it features a flat face on one side and a rounded hemisphere on the other. Workshop tasks such as shaping malleable metals and rounding over rivets rely on this rounded peen. When working with finished assemblies or delicate materials, steel hammers deliver too harsh an impact. Rubber and wooden mallets deliver a softer blow than steel hammers, helping you avoid damaging a workpiece. Similarly, a dead-blow hammer contains loose material, such as steel shot or sand, which shifts forward during impact to reduce rebound when it strikes.

Punches have different purposes: prick and center punches mark metal, while pin punches are struck to drive out pins; some other types of punches cut holes. A prick punch features a sharp point used to establish precise layout marks in metal; this point is generally sharper than the point of a center punch. Once layout lines are marked, a center punch is used to create a dimpled indentation in metal. This dimple serves as a starter guide that keeps a twist drill bit centered at the start of drilling a hole. For removing hardware, pin punches feature straight-sided tips designed to drive out solid pins, whereas a specialized roll-pin punch is specifically designed for hollow roll pins.

Metalworking chisels are struck to cut or chip metal; other types of chisels are made for wood or masonry. A cold chisel is a hardened steel tool designed to cut or chip unheated metal. When specialized shapes or grooves are required, alternative chisel designs are used. A cape chisel features a narrow cutting edge designed for cutting keyways and other narrow grooves in metal. To clean out sharp internal corners or carve V-grooves, a diamond-point chisel is selected due to its diamond-shaped point.

Workshop safety with striking tools requires careful inspection before every swing. Never strike hardened steel tools with a claw hammer, because either tool can chip under the heavy impact and send metal fragments flying through the air. Additionally, never strike a chisel or punch that has developed a mushroomed striking head. As a tool is repeatedly hammered, the struck end can flare outward into a ragged lip; this flared metal can easily chip off and fly when struck.

Saws, Snips, Files, and Rasps

Cutting and smoothing tools remove material through sawing, shearing, or abrasion. In woodworking, hand saws are divided by their tooth geometry and cutting direction relative to the wood grain. A rip saw has chisel-shaped teeth designed to cut wood along the grain; a crosscut saw has knife-like teeth designed to cut across it. In contrast, a crosscut saw features triangular, knife-edged teeth beveled to cut across the natural grain of timber. When intricate curves or tight decorative shapes are required in wood, a coping saw is used; it features a thin, flexible blade held under tension within a C-shaped frame.

When cutting metal, the primary hand tool is the hacksaw. Hacksaw blades are installed into the frame with the teeth pointing forward, cutting material primarily on the push stroke. Hacksaw blade pitch is measured in teeth per inch, with higher tooth counts suited for thinner metals. To ensure smooth operation and prevent equipment failure, at least three consecutive hacksaw teeth should be in contact with the workpiece simultaneously; having fewer teeth engaging the material can cause the teeth to straddle the edge and strip off.

For cutting thin sheet metal by hand, sheet metal shears known as aviation snips are color-coded to indicate their cutting direction. Red-handled aviation snips are designed to make tight cuts curving to the left in sheet metal. Green-handled aviation snips are designed to make tight cuts curving to the right. Yellow-handled aviation snips are generally used for straight cuts and gentle curves. Selecting the proper snip helps the waste metal curl away from the cut line, reducing binding.

Files and rasps abrade surfaces to smooth edges or remove stock. A single-cut file features one set of parallel diagonal teeth and generally leaves a smoother finish than a comparable double-cut file. A double-cut file features two intersecting sets of diagonal teeth that cut aggressively and remove metal rapidly. When working with wood and soft materials rather than metal, a wood rasp is preferred; it features coarse, individually raised teeth designed for aggressive stock removal.

Wrenches and Socket Systems

Wrenches apply torque to turn threaded fasteners such as bolts and nuts. An open-end wrench features parallel jaws that slip onto a fastener from the side; many open-end wrenches have an opening at each end of the handle. A box-end wrench completely surrounds the fastener head and grips it on multiple sides, which helps reduce slipping and rounding off the fastener corners. A combination wrench unites both styles, featuring an open-end jaw on one side and a box-end head of the identical size on the other.

Box-end wrenches and socket drives are commonly configured with either six-point or twelve-point openings. Six-point box wrenches provide maximum surface contact on hex fasteners and resist rounding better than twelve-point wrenches when breaking loose tight hardware. Twelve-point box wrenches grip hex heads at more frequent intervals, requiring only thirty degrees of swing arc to reset the wrench; this small swing arc makes twelve-point wrenches ideal for confined spaces where handle movement is restricted.

Adjustable and specialized wrenches handle irregular or non-standard hardware. An adjustable wrench features one fixed jaw and one movable jaw operated by a worm screw. When using an adjustable wrench, always turn it toward the movable jaw so that most of the force bears on the fixed jaw rather than straining the worm screw mechanism. A pipe wrench features serrated, hardened steel jaws designed to dig into cylindrical pipe surfaces to grip and turn smooth round pipe. For recessed hexagonal drive screws, an Allen wrench is used, which is an L-shaped hexagonal steel bar.

Sockets paired with a ratchet can speed up fastener removal; a socket paired with a torque wrench can be used to tighten a fastener to a specified torque. A ratcheting socket wrench turns a fastener without requiring you to lift and reposition the wrench after each stroke. When nuts are seated on extended threaded studs, standard sockets cannot reach down far enough; deep sockets provide the necessary clearance to reach these nuts. When critical components must be assembled to exact engineering specifications, a torque wrench is used to tighten a fastener to a specified torque, which is a measure of twisting force. For general safety, pull a wrench rather than push it when practical, and keep your hands clear of sharp edges in case the wrench slips.

Pliers and Fastener Drivers

Pliers provide mechanical advantage for gripping, bending, turning, and cutting small components. Slip-joint pliers feature a slotted pivot pin that adjusts between two jaw-opening widths for general gripping tasks. Tongue-and-groove pliers feature an adjustable pivot with multiple positions, allowing their jaws to expand and grip objects such as pipes of different sizes. Locking pliers utilize an over-center toggle mechanism and a threaded knob to adjust jaw spacing and clamp rigidly onto workpieces, holding them without continuous hand pressure.

Specialized pliers handle delicate wirework and cutting. Needle-nose pliers feature elongated, tapered jaws designed to manipulate fine wire and reach confined spaces that fingers or wider pliers cannot access. Diagonal cutting pliers feature angled cutting jaws specifically used to cut wire. When wire must be cut completely flush against a surface without leaving a sharp protruding tip, a specialized flush cutter is used. To prepare electrical connections, wire strippers provide size-marked notches that remove insulation cleanly without nicking the metal conductor when the correct notch is selected.

Screwdrivers and specialty drivers must match the head profile of a fastener precisely to avoid damaging hardware. A slotted screwdriver features a flat blade matched to fasteners with a single straight groove. If a screwdriver blade is too narrow or thin for the screw slot, it can slip out and damage the screw head. A Phillips screwdriver features a cross-shaped tip designed for Phillips screws; however, it may slip out of the recess, an action known as camming out, if too much torque is applied. A Frearson screwdriver features a sharp, pointed cruciform tip that seats deeply and resists cam-out better than a Phillips driver. A Torx driver features a six-lobed, star-shaped tip that transfers torque with less tendency to cam out than a Phillips driver. A Robertson driver features a square-shaped tip that locks firmly into matching square-recess screws. A nut driver resembles a screwdriver in handle design but terminates in a cylindrical socket used to drive small hex nuts and sheet-metal screws.

Misusing hand tools can quickly cause tool failure or personal injury. Screwdrivers are intended solely for driving fasteners and should never be used as pry bars, wedges, or chisels. Using a screwdriver blade as a lever can bend the shank or snap the tip, creating a serious hazard.

Shop Information Strategy and Workshop Safety

The Shop Information subtest evaluates your knowledge of common tools, shop practices, and basic workshop terms. Shop Information is a separate subtest on the CAT-ASVAB and PiCAT; on the paper-and-pencil ASVAB, including the paper-and-pencil student version, shop questions are combined with auto questions in an Auto and Shop Information subtest. Testing formats vary by site; a MET site is a Military Entrance Test site. In all testing environments, hand tool questions demand quick, accurate identification of a tool's primary purpose and proper safety conventions. No calculator is permitted on the ASVAB, making conceptual understanding and memorization of workshop facts essential.

Understanding how your test is scored helps you focus your study efforts effectively. The Armed Forces Qualification Test (AFQT) score determines basic military enlistment eligibility and is derived solely from four academic subtests: Arithmetic Reasoning (AR), Mathematics Knowledge (MK), Word Knowledge (WK), and Paragraph Comprehension (PC). Shop Information does not count toward your AFQT score. Instead, Shop Information scores can contribute to branch-specific composite scores used in determining eligibility for certain military jobs; each branch sets its own requirements, which can change. Minimum qualifying scores and job qualifications are set independently by each military branch and can change over time.

For ASVAB preparation, learn basic workshop safety principles alongside tool names and uses. Always inspect striking and cutting tools before use; never use a punch or chisel with a mushroomed head, as the flared metal can break off and fly under a hammer blow. Never strike hardened steel with a claw hammer; when practical, pull a wrench rather than push it, and position yourself so a slip will not drive your hand into a sharp edge. Finally, ensure that cutting tools engage material properly, such as verifying that at least three consecutive hacksaw teeth rest on a workpiece, to preserve your tools and maintain a safe workspace.