Steel Machetes

History An early stone hammer The use of simple tools dates to about 2,400,000 BCE when various shaped stones were used to strike wood, bone, or other stones to break them apart and shape them.

Stones attached to sticks with strips of leather or animal sinew were being used as hammers by about 30,000 BCE during the middle of the Paleolithic Stone Age. Its archeological record means it is perhaps the oldest human tool known. Designs and variations The essential part of a hammer is the head, a compact solid mass that is able to deliver the blow to the intended target without itself deforming.

The opposite side may have a ball, as in the ball-peen hammer and the cow hammer. Some upholstery hammers have a magnetized appendage, to pick up tacks. In the hatchet the hammer head is secondary to the cutting edge of the tool. As the impact between steel hammer heads and the objects being hit can, and does, create sparks, which in some industries such as underground coal mining with methane gas, or in other hazardous environments containing flammable gases and vapours, can be dangerous and risk igniting the gases. In these environments, a variety of non-sparking metal tools are used, being principally, aluminium or beryllium copper-headed hammers. In recent years the handles have been made of durable plastic or rubber. The hammer varies at the top; some are larger than others giving a larger surface area to hit different sized nails and such. Popular hand-powered variations include: carpenter’s hammers (used for nailing), such as the framing hammer and the claw hammer upholstery hammer construction hammers, including the sledgehammer drilling hammer – a lightweight, short handled sledgehammer Ball-peen hammer, or mechanic’s hammer Soft-faced hammer cross-peen hammer, or Warrington hammer mallets, including the rubber hammer and dead blow hammer. Splitting maul stonemason’s hammer Geologist’s hammer or rock pick lump hammer, or club hammer gavel, used by judges and presiding authorities in general Tinner’s Hammer Claw hammer Framing hammer Geologist’s hammer Upholstery hammer Cross-peen hammer Ball-peen hammer Rubber mallet Wooden mallet Sledgehammer Stone tapping hammer Perforated hammer head of stone Long cross-face hammer (blacksmithing) Twist hammer (blacksmithing) Dog-head hammer (blacksmithing) Ball pane hammer Straight pane sledgehammer Bush hammer Mechanically-powered hammer Mechanically-powered hammers often look quite different from the hand tools, but nevertheless most of them work on the same principle. They include: jackhammer steam hammer trip hammer hammer drill, that combines a jackhammer-like mechanism with a drill In professional framing carpentry, the hammer has almost been completely replaced by the nail gun. In professional upholstery, its chief competitor is the staple gun. Tools used in conjunction with hammers Woodsplitting wedge – hit with a sledgehammer for splitting wood. Woodsplitting maul – can be hit with a sledgehammer for splitting wood. Masonry star drill Chisel Punch Anvil The physics of hammering Hammer as a force amplifier A hammer is basically a force amplifier that works by converting mechanical work into kinetic energy and back. In the swing that precedes each blow, a certain amount of kinetic energy gets stored in the hammer’s head, equal to the length D of the swing times the force f produced by the muscles of the arm and by gravity. When the hammer strikes, the head gets stopped by an opposite force coming from the target; which is equal and opposite to the force applied by the head to the target. If the target is a hard and heavy object, or if it is resting on some sort of anvil, the head can travel only a very short distance d before stopping. Since the stopping force F times that distance must be equal to the head’s kinetic energy, it follows that F will be much greater than the original driving force f roughly, by a factor D/d.

In this way, great strength is not needed to produce a force strong enough to bend steel, or crack the hardest stone. Effect of the head’s mass The amount of energy delivered to the target by the hammer-blow is equivalent to one half the mass of the head times the square of the head’s speed at the time of impact (). While the energy delivered to the target increases linearly with mass, it increases geometrically with the speed (see the effect of the handle, below). High tech titanium heads are lighter and allow for longer handles, thus increasing velocity and delivering more energy with less arm fatigue than that of a steel head hammer of the same weight. As hammers must be used in many circumstances, where the position of the person using them cannot be taken for granted, trade-offs are made for the sake of practicality. In areas where one has plenty of room, a long handle with a heavy head (like a sledge hammer) can deliver the maximum amount of energy to the target. It is not practical to use such a large hammer for all tasks, however, and thus the overall design has been modified repeatedly to achieve the optimum utility in a wide variety of situations. Effect of the handle The handle of the hammer helps in several ways. It keeps the user’s hands away from the point of impact. It provides a broad area that is better-suited for gripping by the hand. Most importantly, it allows the user to maximize the speed of the head on each blow.

The primary constraint on additional handle length is the lack of space in which to swing the hammer. This is why sledge hammers, largely used in open spaces, can have handles that are much longer than a standard carpenter’s hammer. The second most important constraint is more subtle. Even without considering the effects of fatigue, the longer the handle, the harder it is to guide the head of the hammer to its target at full speed. Most designs are a compromise between practicality and energy efficiency. Too long a handle: the hammer is inefficient because it delivers force to the wrong place, off-target. Too short a handle: the hammer is inefficient because it doesn’t deliver enough force, requiring more blows to complete a given task. Recently, modifications have also been made with respect to the effect of the hammer on the user.

A titanium head has about 3% recoil and can result in greater efficiency and less fatigue when compared to a steel head with about 27% recoil. Handles made of shock-absorbing materials or varying angles attempt to make it easier for the user to continue to wield this age-old device, even as nail guns and other powered drivers encroach on its traditional field of use. War hammers Main article: War hammer The concept of putting a handle on a weight to make it more convenient to use may well have led to the very first weapons ever invented.[citation needed] The club is basically a variant of a hammer. In the Middle Ages, the war hammer became popular when edged weapons could no longer easily penetrate some forms of armour.[citation needed] Symbolic hammers The hammer, being one of the most used tools by Homo sapiens, has been used very much in symbols and arms. In the Middle Ages it was used often in blacksmith guild logos, as well as in many family symbols. The most recognised symbol with a hammer in it is the Hammer and Sickle, which was the symbol of the former Soviet Union and is very interlinked with Communism/Socialism. The hammer in this symbol represents the industrial working class (and the sickle the agricultural working class). The hammer is used in some coat of arms in (former) socialist countries like East Germany.

In Norse Mythology, Thor, the god of thunder and lightning, wields a hammer named Mjolnir. Many artifacts of decorative hammers have been found, leading modern practitioners of this religion to often wear reproductions as a sign of their faith. References ^ Semaw, S., M. J. Rogers, J. Quade, P. R. Renne, R. F. Butler, M. Domnguez-Rodrigo, D. Stout, W. S. Hart, T. Pickering, and S. W. Simpson. 2003. 2.6-Million-year-old stone tools and associated bones from OGS-6 and OGS-7, Gona, Afar, Ethiopia. Journal of Human Evolution 45:169-177. ^ 2.5-million-year-old stone tools from Gona, Ethiopia S. Semaw*, P. Renne, J. W. K. Harris*, C. S. Feibel*, R. L. Bernor, N. Fesseha & K. Mowbray* Nature 385, 333-336 (23 January 1997) | doi:10.1038/385333a0; Accepted 25 November 1996 External links Look up hammer in Wiktionary, the free dictionary. Hammer types images and descriptions. The Hammer Museum v  d  e Types of tools Cutting tools Blade  Bolt cutter  Broach  Ceramic tile cutter  Chisel  Coping saw  Countersink  Diamond blade  Diamond tool  Drill bit  Endmill  File  Fretsaw  Froe  Glass cutter  Grater  Hacksaw  Hand saw  Knife  Milling cutter  Miter saw  Pipecutter  Plane  Razor  Reamer  Saw  Scalpel  Scissors  Slasher  Surform  Switchblade  Tap and die  Tool bit  Utility knife  Water jet cutter  Wire cutter  Wire stripper Garden tools Adze  Axe  Billhook  Bow saw  Cultivator  Earth auger  Edger  Garden fork  Garden hose  Garden trowel  Hedge trimmer  Hoe  Hori hori  Irrigation sprinkler  Lawn aerator  Lawn mower  Lawn sweeper  Leaf blower  Loppers  Machete  Mattock  Pickaxe  Pitchfork  Plough (plow)  Post hole digger  Pruning shears (secateurs)  Rake  Roller  Rotary tiller  Scythe  Sickle  Spade  Splitting maul  String trimmer Hand tools Block plane  BNC inserter/remover  Brace  Bradawl  Breaker bar  Broom  Brush  Card scraper  Caulking gun  Clamp  Crimping pliers  Crowbar  Fish tape  Hammer  Hawk  Hex key  Locking pliers  Mallet  Miter box  Nut driver  Pipe wrench  Pliers  Punch  Punch down tool  Putty knife  Ratchet  Scratch awl  Screwdriver  Sledgehammer   Sponge  Squeegee  Staple gun  Stitching awl  Torque wrench  Trowel  Upholstery hammer  Wrench (spanner) Machine tools Broaching machine  Drill press  Gear shaper  Grinding machine  Hobbing machine  Jig borer  Lathe  Metalworking lathe  Milling machine  Planer  Screw machine  Shaper  Turret lathe Power tools Angle grinder  Band saw  Belt sander  Blow torch  Chainsaw  Chop saw  Circular saw  Concrete saw  Crusher  Cutting torch  Die grinder  Drill  Glue gun  Grinding machine  Heat gun  Impact wrench  Jigsaw  Jointer  Nail gun  Radial arm saw  Random orbital sander  Reciprocating saw  Rotary tool  Router table  Sander  Scroll saw  Soldering gun  Soldering iron  Steam box  Table saw  Thickness planer  Welding  Wood router  Wood shaper Measuring & Alignment tools Caliper  Jig  Micrometer  Pencil  Plumb-bob  Ruler  Sliding T bevel  Spirit level  Square  Tape measure Other Antique tools  Halligan bar  Kelly tool  Ladder  Thau claw  Toolbox  Vise  Workbench v  d  e Metalworking   Tools Cutting machines Water jet cutter  Band saw  Cold saw  Laser  Miter saw  Plasma Cutting tools Broach  Burr  Chisel  Counterbore  Countersink  End mill  File  Guillotine shear  Hand scraper  Milling cutter  Nibbler  Reamer  Throatless shear  Tipped tool  Tool bit Forming tools Brake  Die  English Wheel  Flypress  Hydraulic press  Machine press  Punch press  Stamping press Hand tools Clamp  Combination square  Drift pin  File card  Hacksaw  Hammer  Hand scraper  Machinist square  Magnetic base  Needlegun scaler  Pipe and tube bender  Pliers  Punch  Saw piercing  Scriber  Tap and die  Tongs  Vise  Workbench  Wrench Machine tooling Angle plate  Chuck  Collet  Jig  Fixture  Indexing head  Lathe center  Machine taper  Magnetic base  Mandrel  Rotary table  Wiggler Measuring instruments Bore gauge  Caliper  Comparator  Dial indicator  Engineer’s blue  Feeler  Center gauge and fishtail gauge  Gauge block  Gauge  Go-NoGo  Machinist square  Marking blue  Marking gauge  Marking out  Micrometer  Radius gauge  Scale  Sine bar  Spirit level  Straightedge  Surface plate  Tape measure  Thread pitch  Height gauge  Vernier scale  Wiggler Smithing tools Anvil  Forge  Fuller  Hardy hole  Hardy tools  Pritchel  Slack tub  Steam hammer  Swage block  Trip hammer Casting  Fabrication  Forming  Jewellery  Machining  Metallurgy  Smithing  Tools & Terminology  Welding Categories: Hammers | Blunt weapons | Mechanical hand tools | Metalworking hand tools | Woodworking hand tools | Hand toolsHidden categories: Articles needing additional references from December 2009 | All articles needing additional references | All articles with unsourced statements | Articles with unsourced statements from February 2007 | Articles with unsourced statements from May 2008

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I don’t want to cover just the expensive uber-cool blades. We’ll go everywhere. Here I discuss the great value that the Cold Steel 12″ Bowie knife represents. Even at just $20 it’s a contender in the survival/combat knife category. Having good steel, a descent sheath, good handle, and reasonable weight you should own at least two. Just remember to get it sharpened properly first! ADD: The 12″ Bowie may lack some hacking capability (in the woods) due to its lighter blade too. Didn’t mention that.