9.1 Hand Tools, Measuring Instruments, and Cutting Implements

9.1 Hand Tools, Measuring Instruments, and Cutting Implements

Exam Focus: The Shop Information (SI) subtest on the Computer Adaptive ASVAB evaluates your understanding of trade tools, mechanical devices, fabrication techniques, and workshop safety. In the computerized format, SI is administered as an independent 10-scored-question subtest with a 6-minute time limit (an average of 36 seconds per question, tied with Word Knowledge as the tightest pace on the battery). Because SI scores directly populate composite line scores for Mechanical Maintenance (MM), General Maintenance (GM), Combat Operations (CO), and Surveillance & Communications (SC), mastering tool taxonomy and mechanical principles is essential for securing technical military occupational specialties.

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Measuring, Layout & Precision Marking Instruments

Dimensional accuracy is the prerequisite for all structural fabrication and mechanical assembly. The ASVAB tests your ability to identify layout instruments, determine their resolution limits, and interpret precision measurement scales.

+----------------------------------------------------------------------------------------------------+
|                               MEASURING & LAYOUT INSTRUMENT TAXONOMY                               |
+----------------------+--------------------+--------------------------------------------------------+
| Tool Name            | Scale / Resolution | Primary Trade Application                              |
+----------------------+--------------------+--------------------------------------------------------+
| Steel Rule           | 1/64" or 0.5 mm    | Direct linear measurement and straightedge scribing    |
| Tape Measure         | 1/16" or 1 mm      | Long-distance layout; floating true-zero end hook      |
| Try Square           | Fixed 90°          | Checking 90° right angles on dressed lumber edges      |
| Framing Square       | 24" x 16" Body/Tong| Rafter scales, stair stringer layout, roof framing     |
| Combination Square   | 90°, 45°, Center   | Multi-angle layout, center finding, depth gauging      |
| Sliding T-Bevel      | Adjustable Angle   | Measuring, locking, and transferring arbitrary angles  |
| Vernier / Dial Calip | 0.001" (0.02 mm)   | Inside diameter, outside diameter, and hole depth      |
| Micrometer           | 0.0001" (0.002 mm) | Ultra-precision shaft diameter and plate thickness     |
| Plumb Bob            | Gravity Vertical   | Establishing true vertical alignment over distances    |
| Spirit Level         | Bubble Vials       | Verifying true horizontal (level) and vertical (plumb) |
+----------------------+--------------------+--------------------------------------------------------+

1. Squares & Angular Layout Tools

• Try Square: Built with a thin steel blade fixed permanently at a $90^\circ$ angle into a thick wooden or cast-metal handle (the stock). Used primarily in joinery and cabinetry to check squareness and mark perpendicular cut lines across narrow boards.
• Framing Square (Carpenter's Square): A large, flat, L-shaped steel or aluminum square consisting of a $24\text{ inch} \times 2\text{ inch}$ body and a $16\text{ inch} \times 1.5\text{ inch}$ tongue. It contains imprinted conversion tables, rafter length tables, and octagon scales used for structural framing, roof rafter calculation, and stair stringer layout.
• Combination Square: A 12-inch grooved steel blade fitted with three interchangeable sliding heads that lock with a knurled thumb nut:
  1. Square Head (Miter Head): Features reference faces at both $90^\circ$ and $45^\circ$; contains an integrated spirit bubble vial and a removable brass scratch scriber.
  2. Center Head: Features a $90^\circ$ V-shaped opening that bisects cylindrical stock, allowing a scriber to locate the exact center of round metal rods or wooden dowels.
  3. Protractor Head: Contains a revolving turret graduated from $0^\circ$ to $180^\circ$ in both directions to lay out and verify non-standard angles.
• Sliding T-Bevel: An adjustable steel blade that pivots inside a slotted handle and locks via a thumbscrew. It carries no degree markings; its function is to duplicate an existing angle from a workpiece or blueprint and transfer that angle to another component or machine table.

                  COMBINATION SQUARE HEAD CONFIGURATIONS
     
      [ SQUARE / MITER HEAD ]         [ CENTER HEAD ]        [ PROTRACTOR HEAD ]
          |---|                            \     /                 .---.
     90°  |   |  45°                        \   /                /   |   \
    <-----'   '----->                        \ /                | 0° | 180°|
      [Vial] [Scriber]                     (Round Rod)           \   |   /
                                                ▲                  '---'
                                         Locates Center        0° to 180° Scale

2. Precision Measurement: Calipers & Micrometers

• Calipers:
  • Firm-Joint Calipers: Divided into inside calipers (legs curved outward to measure internal bores, hole diameters, and slots) and outside calipers (legs bowed inward to measure external shaft diameters and plate thickness). Measurements taken with firm-joint calipers must be transferred to a precision steel rule for reading.
  • Dial & Vernier Calipers: Slide instruments featuring external measuring jaws, internal measuring nibs, and a slender protruding depth probe. Dial calipers indicate whole inches on the main beam and thousandths ($0.001\text{ inch}$) on the rotating dial face.
• The Micrometer Screw Gauge: The highest-precision handheld measuring instrument on the ASVAB, measuring down to $0.0001\text{ inch}$ ($0.002\text{ mm}$).
  • Anatomy: Composed of a rigid semi-circular U-frame, a stationary anvil, a movable threaded spindle, a fixed graduated sleeve (barrel), a rotating graduated thimble, and a knurled ratchet stop.
  • Mechanical Principle: The internal spindle screw is precision-ground with a pitch of 40 threads per inch (TPI). One complete $360^\circ$ revolution of the thimble moves the spindle forward or backward by exactly $1/40\text{ inch} = 0.025\text{ inch}$.
  • Reading an Imperial Micrometer (Step-by-Step):
    1. Read the Sleeve Major Numbers: Numbered lines ($0, 1, 2, \dots, 9$) each represent $0.100\text{ inch}$.
    2. Read the Sleeve Subdivisions: Each small unnumbered hash mark between major numbers represents $0.025\text{ inch}$ ($1/40\text{ inch}$).
    3. Read the Thimble Graduations: The beveled edge of the thimble is divided into 25 equal marks ($0\text{ to }24$), where each line equals $0.001\text{ inch}$.
    4. Sum the Components: Total Dimension = Major Sleeve + Minor Sleeve + Thimble Reading.
    5. Ratchet Stop Usage: Always turn the ratchet stop at the end of the thimble until it clicks 2 to 3 times; this applies uniform measuring pressure and prevents overtightening the spindle against the workpiece.

                            OUTSIDE MICROMETER ANATOMY
                             
          Fixed Anvil       Movable Spindle       Graduated Sleeve   Graduated Thimble
            +-----+           +========+          +--------------+   +-------------+
            |     |           |        |          | 0  1  2  3   |---| 0 ---       |
            +-----+           +========+          +--------------+   | 20 ---      |
               |                  |                                  | 15 ---      |
        +------v------------------v------+                           +------v------+
        |                                |                                  |
        |       RIGID CAST U-FRAME       |                             Ratchet Stop
        |                                |                                  |
        +--------------------------------+                                  v
                                                                          [===]

Step-by-Step Micrometer Reading Example

• Observed Sleeve: Visible major number is $3$ ($0.300"$). Past the $3$, exactly two minor subdivision lines are exposed ($2 \times 0.025" = 0.050"$).
• Observed Thimble: The thimble line aligned with the sleeve horizontal index line is $17$ ($17 \times 0.001" = 0.017"$).
• Total Dimension: $\text{Total} = 0.300" + 0.050" + 0.017" = \mathbf{0.367\text{ inch}}$

3. Leveling & Marking Tools

• Spirit Level: Contains sealed glass or acrylic vials filled with alcohol or mineral spirits and an air bubble. When centered between the etched witness lines, the vial indicates true horizontal (level), true vertical (plumb), or $45^\circ$ angular slope.
• Plumb Bob: A pointed, heavy conical brass or steel weight suspended from a string. It utilizes the Earth's gravitational field to establish a true vertical reference line over structural heights where a spirit level is too short.
• Scratch Awl: A hardened, needle-pointed steel tool used to scribe fine, indelible layout lines directly into wood or sheet metal.
• Center Punch vs. Prick Punch:
  • Prick Punch: Features a narrow, sharp $30^\circ\text{ to }60^\circ$ conical point used for precise layout scribing and light point marking.
  • Center Punch: Features a blunt, heavy $90^\circ$ point struck with a ball-peen hammer to produce a deep conical indentation in metal. This dimple seats the tip of a twist drill bit, preventing the drill from wandering ("walking") across the workpiece upon startup.

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Striking Tools & Impact Mechanics

Hammers and mallets convert kinetic energy into mechanical work for driving fasteners, shaping materials, seating assemblies, and demolition. Striking tools must be carefully selected based on material hardness to avoid fracturing hardened tools or marring finished work.

+----------------------------------------------------------------------------------------------------+
|                                   STRIKING TOOL CLASSIFICATIONS                                    |
+----------------------+----------------------+------------------------------------------------------+
| Tool Name            | Distinctive Geometry | Primary Trade Function & Application                 |
+----------------------+----------------------+------------------------------------------------------+
| Curved Claw Hammer   | Curved split claw    | Driving common nails; maximum nail extraction force  |
| Straight Claw Hammer | Chisel-like rip claw | Framing, prying lumber, subfloor demolition          |
| Ball-Peen Hammer     | Flat face + ball end | Metalworking, striking cold chisels, peening rivets  |
| Dead-Blow Hammer     | Steel shot fill      | Zero rebound; 100% energy transfer; non-marring      |
| Rubber / Wood Mallet | Soft face (wood/elast| Assembling furniture joints, shaping thin sheet metal|
| Sledgehammer         | 2 to 20 lb steel head| Heavy demolition, driving foundation stakes and wedges|
+----------------------+----------------------+------------------------------------------------------+

1. Carpentry Claw Hammers

• Curved Claw Hammer: Features a smooth or textured striking face on one side and a deeply curved split claw on the opposing side. The curved contour functions as a first-class lever when fulcrumed against a wood surface, maximizing mechanical advantage for extracting bent nails.
• Straight (Rip) Claw Hammer: Features a flatter, wedge-shaped claw extending straight out from the hammer head. Designed for framing carpenters to wedge between structural studs, pry apart formwork, and rip up subflooring during demolition.

2. Metalworking Hammers & Mallets

• Ball-Peen Hammer (Machinist's Hammer): The essential metalworking striking tool. Features a hardened flat face with beveled edges designed for striking punches, cold chisels, and star drills, and a hemispherical ball peen on the reverse side. The ball peen is used for expanding solid rivet shanks ("peening"), stretching sheet metal, and tapping gasket profiles against engine mating surfaces.
• Dead-Blow Hammer: Built with a hollow composite or polyurethane head partially filled with loose steel shot or lead pellets. When the face strikes a workpiece, the internal shot shifts forward milliseconds after the primary impact, completely canceling the elastic rebound force. This delivers full kinetic momentum directly into the workpiece without bounce-back and without marring delicate machined surfaces.
• Wooden & Rawhide Mallets: Engineered to deliver soft, non-sparking, non-marring blows. Essential for striking wooden-handled wood chisels (which would shatter or mushroom under a steel hammer face) and tapping tight mortise-and-tenon furniture joints into place.

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Clamping, Holding & Workholding Tools

Secure workholding is fundamental to personal safety and manufacturing precision. A loose workpiece can spin, bind, or kick back into the operator.

+----------------------------------------------------------------------------------------------------+
|                                 WORKHOLDING & CLAMPING TAXONOMY                                    |
+----------------------+-----------------------+-----------------------------------------------------+
| Tool Name            | Mechanism / Feature   | Primary Trade Application                           |
+----------------------+-----------------------+-----------------------------------------------------+
| Bench Vise           | Cast iron; lead screw | Heavy workbench holding, bending, metal filing      |
| C-Clamp              | C-frame; swivel pad   | Localized high-pressure clamping in welding/metal   |
| Pipe / Bar Clamp     | Long rail; clutch disc| Edge-gluing wide wooden panels, cabinet carcasses   |
| Spring Clamp         | Pivoting spring jaws  | Rapid, light-pressure holding of trim and veneers   |
| Locking Pliers       | Over-center toggle    | Clamping seized hardware, acting as handheld vise   |
| Tongue-and-Groove    | Curved channel tracks | Gripping large-diameter plumbing pipes and fittings |
| Needle-Nose Pliers   | Long, slender jaws    | Bending electrical wire loops, tight cavity retrieval|
+----------------------+-----------------------+-----------------------------------------------------+

1. Vises & Clamps

• Bench Vise (Machinist's Vise): A heavy cast-iron or forged steel fixture bolted to the workbench. Consists of a stationary jaw, a movable jaw driven along a heavy Acme lead screw, and integrated serrated pipe jaws beneath the main flats. When clamping soft metals (copper, aluminum) or finished woodwork, magnetic soft jaw covers (made of brass, aluminum, or polyurethane) must be installed to prevent the hardened steel serrations from gouging the material.
• C-Clamp: Consists of a rigid C-shaped steel frame, a threaded steel screw spindle, and a swiveling shoe pad that conforms to angled surfaces. Provides extreme localized clamping pressure for welding fit-up and metal fabrication.
• Pipe Clamps & Bar Clamps: Feature a fixed stop head and an adjustable sliding tail stop mounted along a steel I-beam or length of threaded black iron pipe. Used in cabinet shops to clamp broad tabletops, cabinet cases, and long frame assemblies during glue cure.

2. Pliers Taxonomy

• Slip-Joint Pliers: Feature an oval pivot slot that allows the center pin to shift between two positions, changing the jaw opening width to grip varying sizes of fasteners and round rods.
• Tongue-and-Groove Pliers (Channel-Lock / Water-Pump Pliers): Feature curved interlocking tongue-and-groove tracks that allow the parallel jaws to adjust across wide diameters. Designed specifically for plumbing pipe fittings and round conduits.
• Locking Pliers (Vise-Grips): Incorporate an adjustable over-center toggle linkage controlled by a knurled screw in the base of the handle. When squeezed shut, the jaws lock solidly onto the workpiece with tremendous mechanical force, functioning as a portable handheld vise. An internal release lever pops the linkage open.
• Diagonal Cutting Pliers (Dikes): Feature sharp, angled side-cutting jaws designed exclusively for flush-shearing electrical wires, zip-ties, cotter pins, and soft wire nails. They are not designed for gripping or turning nuts.
• Linesman's Pliers: Heavy-duty pliers with broad serrated gripping jaws and integrated side wire cutters. Used by electricians for twisting multi-conductor wire splices, pulling heavy cables through conduit, and cutting hard wire.

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Turning Tools, Wrenches & Screwdrivers

Turning tools apply rotational torque to tighten or loosen threaded fasteners. Selecting the correct size and drive profile prevents stripping fastener heads and rounding off hex corners.

+----------------------------------------------------------------------------------------------------+
|                                    WRENCH & SPANNER GEOMETRIES                                     |
+----------------------+----------------------+------------------------------------------------------+
| Wrench Type          | Jaw Configuration    | Operating Mechanics & Torque Capacity                |
+----------------------+----------------------+------------------------------------------------------+
| Open-End Wrench      | U-shaped 15° jaws    | Fast engagement on hex flats; enables 30° flip swing |
| Box-End Wrench       | Enclosed 6 or 12-pt  | Full perimeter contact; highest torque; no rounding  |
| Combination Wrench   | Open end + Box end   | Versatile dual-ended tool of identical nominal size  |
| Adjustable (Crescent)| Movable worm screw   | Variable size; MUST pull toward movable jaw          |
| Pipe Wrench (Stillson| Floating serrated jaw| Deep bite on round iron pipe; NEVER on hex fasteners |
| Socket Wrench/Ratchet| Square drive ratchet | Rapid multi-directional turning with modular sockets |
| Torque Wrench        | Calibrated indicator | Tightening fasteners to exact specified torque limits|
+----------------------+----------------------+------------------------------------------------------+

1. Wrenches & Spanners

• Open-End Wrench: Features open U-shaped jaws contacting two opposing flats of a hexagonal fastener. The jaw axis is angled at $15^\circ$ relative to the handle centerline. This design allows the mechanic to rotate a nut in restricted spaces by swinging the wrench through $30^\circ$, flipping the wrench over, and swinging another $30^\circ$.
• Box-End Wrench: Features a continuous closed ring with internal 6-point (hexagonal) or 12-point (double-hex) broaching that completely encircles the fastener head. 6-point box wrenches provide maximum contact area across the fastener flats to withstand heavy torque without slipping; 12-point box wrenches allow engagement every $30^\circ$ for tight-clearance operations.
• Combination Wrench: Features an open-end jaw on one side and a box-end ring of the identical dimensional size on the opposite side, combining speed with final high-torque tightening.
• Adjustable Crescent Wrench: Features a fixed jaw and a movable jaw adjusted via a knurled worm gear.
  • Critical Safety Rule: Always orient the wrench and apply pulling force toward the movable jaw side. This forces the robust fixed jaw to carry the bending load against the handle. Applying torque against the movable jaw overloads the worm track, splaying the jaws and stripping fastener corners.
• Pipe Wrench (Stillson Wrench): Built with heavy cast iron and deeply hardened, serrated floating jaws. The hook jaw pivots in its frame; as torque is applied, the jaws pivot and bite deeper into smooth cylindrical iron pipe.
  • Shop Exam Warning: Never use a pipe wrench on hexagonal bolts, nuts, or brass plumbing fittings. The sharp teeth will gouge, crush, and permanently destroy the fastener head.
• Socket Wrenches & Ratchets: Modular turning systems featuring square drive ratchets (standard square drive sizes: $1/4\text{ inch}$, $3/8\text{ inch}$, $1/2\text{ inch}$, and $3/4\text{ inch}$) driving detachable 6-point or 12-point sockets. Essential accessories include:
  • Breaker Bar: A long, solid steel non-ratcheting handle used to break loose seized or over-torqued fasteners where a ratcheting mechanism would break.
  • Extensions & Universal Joints: Extend socket reach into deep engine cavities and allow off-axis turning.
• Torque Wrenches: Precision fastening tools calibrated in foot-pounds ($\text{ft-lbs}$), inch-pounds ($\text{in-lbs}$), or Newton-meters ($\text{Nm}$):
  • Click-Type: A spring-loaded internal detent breaks over with an audible and tactile click when the dialed torque setting is reached.
  • Beam-Type: A long indicator pointer deflects against a stationary calibrated scale as the handle flexes under applied load.

                              SCREWDRIVER DRIVE GEOMETRIES
                               
    [ SLOTTED / FLAT ]         [ PHILLIPS (+) ]          [ ROBERTSON (SQUARE) ]          [ TORX (STAR) ]
         +-----+                   +---+---+                    +-------+                     * *
         | === |                   |   |   |                    |       |                   *  |  *
         +-----+                   +---+---+                    +-------+                  * --+-- *
                                       |                                                      *
     Single flat blade         Cross-slot profile          Square recessed drive         6-point star recess
     Slips under load          Engineered to cam out       Zero slip; high torque        Maximum torque transfer

2. Screwdrivers & Drive Bits

• Slotted (Flathead): Features a flat wedge-shaped blade fitting a single straight slot. Prone to slipping out under moderate torque, potentially scratching workpieces or puncturing hands.
• Phillips: Features a cross-shaped ($+$) recess with tapered cruciform wings. Engineered originally for automated assembly lines to intentionally cam out (slip upward out of the recess) when a torque limit is reached to avoid shearing off fastener heads.
• Robertson (Square Drive): Features a tapered square recess. Offers outstanding bit retention and virtually eliminates cam-out under heavy driving loads.
• Torx (Star Drive): Features a 6-pointed star recess with vertical sidewalls. Provides maximum contact area and zero cam-out, allowing extreme torque transfer in automotive, aerospace, and deck construction applications.
• Hex / Allen Key: An L-shaped hexagonal steel bar used to turn socket-head cap screws and internal set screws.

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Cutting, Shearing & Shaping Hand Tools

Hand cutting tools sever material through mechanical shearing or chip removal. Understanding tooth geometry, tooth count, and cutting stroke direction is heavily tested on the ASVAB.

+----------------------------------------------------------------------------------------------------+
|                                    HANDSAW TAXONOMY & BLADE MECHANICS                              |
+----------------------+--------------------+-------------+------------------------------------------+
| Saw Type             | Grain Orientation  | TPI Range   | Tooth Geometry & Cutting Action          |
+----------------------+--------------------+-------------+------------------------------------------+
| Crosscut Saw         | Across wood grain  | 8 – 12 TPI  | Alternating beveled knife-like teeth     |
| Ripsaw               | Along (with) grain | 5 – 7 TPI   | Straight 90° chisel-like flat teeth      |
| Backsaw (Tenon Saw)  | Precision joinery  | 12 – 16 TPI | Fine teeth with rigid brass/steel spine  |
| Coping Saw           | Intricate curves   | 15 – 20 TPI | Thin flexible blade in deep steel C-frame|
| Hacksaw              | Metal, PVC, pipe   | 18 – 32 TPI | Rigid frame; teeth MUST point FORWARD    |
+----------------------+--------------------+-------------+------------------------------------------+

1. Wood Handsaws: Crosscut vs. Ripsaw

• Crosscut Saw: Engineered specifically to cut perpendicular to (across) the wood grain. The teeth are filed at alternating $60^\circ\text{ to }70^\circ$ bevel angles, creating a series of sharp, knife-like points on both sides of the blade that slice cleanly across the hollow grain fibers without tearing. Features higher Teeth Per Inch (8 to 12 TPI).
• Ripsaw: Engineered specifically to cut parallel to (with) the wood grain. The teeth are filed straight across at $90^\circ$ like a continuous bank of miniature wood chisels that chisel out wood shavings along the grain channels. Features lower Teeth Per Inch (5 to 7 TPI) with deep, wide gullets to eject large volumes of sawdust quickly.
• Kerf & Tooth Set: The kerf is the width of the cut made by the saw blade. The teeth of a saw blade are alternately bent outward to the left and right (tooth set) so that the kerf cut into the wood is wider than the blade plate itself. This prevents the wood from pinching and binding against the body of the blade during deep cuts.
• Backsaw (Tenon / Dovetail Saw): A fine-toothed rectangular saw with a heavy brass or steel reinforcing spine running along its top back edge. The spine prevents blade flexing, ensuring dead-flat, precision cuts for mortise-and-tenon joints, lap joints, and dovetails.
• Coping Saw: Features a lightweight, deep C-shaped steel frame that tensions an ultra-thin, narrow, flexible blade. The blade can be detached, passed through a drilled starter hole in a board, and retensioned to cut intricate interior scroll patterns and coped molding joints.

                         SAW TOOTH GEOMETRY COMPARISON
                          
      [ CROSSCUT SAW TEETH: 8-12 TPI ]              [ RIPSAW TEETH: 5-7 TPI ]
           /\      /\      /\                          |\       |\       |\
          /  \    /  \    /  \                         | \      | \      | \
         / /\ \  / /\ \  / /\ \                        |  \     |  \     |  \
        --'  '----'  '----'  '--                      +---+----+---+----+---+----+
        Alternating knife-edge bevels                  Straight 90° chisel-face teeth
        Slices across grain fibers cleanly             Chisels wood shavings along grain

2. Metal Cutting: The Hacksaw

• The Hacksaw is the universal hand tool for cutting structural steel angle, bar stock, conduit, and threaded rods.
• Blade Installation Direction (High-Yield ASVAB Rule): Hacksaw blades must ALWAYS be installed with the teeth pointing FORWARD (away from the handle). The hacksaw cuts ONLY on the forward push stroke. Applying heavy downward pressure during the return pull stroke ruins the blade teeth and causes chatter.
• Tooth Selection Rule (The 3-Tooth Rule): Hacksaw blades are rated at 18, 24, or 32 TPI. The fundamental rule of metal cutting dictates that at least 3 consecutive teeth must be in contact with the workpiece thickness at all times. If the metal is thinner than the span of 3 teeth, the material will drop into the gullet, stripping the teeth off the blade.

3. Chisels, Files & Hand Planes

• Wood Chisel: Hardened high-carbon steel tool with a single beveled cutting edge ground at $25^\circ\text{ to }30^\circ$. Used by hand or struck with a wooden/rubber mallet for cutting mortises, paring joints, and cleaning corners. (Never strike a wood chisel with a steel hammer).
• Cold Chisel: Made of tough, heat-treated alloy steel with a blunt double-beveled wedge edge ground at $60^\circ\text{ to }70^\circ$. Designed to be struck with a ball-peen hammer to cut cold (unheated) steel, shear off rusted rivet heads, or split frozen nuts.
• Files & Rasps:
  • Single-Cut File: Features single rows of parallel diagonal teeth; used for smooth finishing, lathe draw-filing, and sharpening tool edges.
  • Double-Cut File: Features two intersecting sets of diagonal teeth forming diamond-shaped cutting points; used for aggressive, rapid stock removal.
  • Bastard Cut: Refers to a medium coarseness grade. Coarseness ranking: Rough $\rightarrow$ Coarse $\rightarrow$ Bastard $\rightarrow$ Second-Cut $\rightarrow$ Smooth $\rightarrow$ Dead Smooth.
  • Operating Rule: Files cut only on the forward push stroke. Relieve pressure on the return stroke. Clean metal particles from clogged teeth using a wire file card.
• Hand Planes:
  • Jack Plane: Medium-length ($12\text{ to }15\text{ inch}$) general-purpose bench plane used for rapid stock removal and truing rough boards.
  • Block Plane: Compact ($6\text{ inch}$) plane with a low-angle blade ($12^\circ\text{ to }20^\circ$) bedded with the bevel facing upward; designed for one-handed trimming of end grain, chamfering edges, and fitting doors.
  • Jointer Plane: Longest hand plane ($20\text{ to }24\text{ inch}$); used to plane long, perfectly flat, straight edges on boards prior to edge-gluing.