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Punch (tool)
A punch is a tool used to indent or create a hole through a hard surface. They usually consist of a hard metal rod with a narrow tip at one end and a broad flat "butt" at the other. When used, the narrower end is pointed against a target surface and the broad end is struck with a hammer or mallet, causing the blunt force of the blow to be transmitted through the rod body and focused more sharply onto a small area. Typically, woodworkers use a ball-peen hammer to strike a punch. Use Punches are used to drive fasteners such as nails and dowels, making a hole, or forming an indentation or impression of the tip on a work piece. Decorative punches may also be used to create a pattern or even form an image. Pin Metal pins and similar connectors are driven in or out of holes using a pin punch. For removal, first use a starter punch to loosen the pin, then use a pin punch to finish. Center A ''center punch'' is used to mark the center of a point. It is usually used t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Automatic Center Punch
An automatic center punch is a hand tool used to produce a dimple in a workpiece (for example, a piece of metal). It performs the same function as an ordinary center punch but without the need for a hammer. When pressed against the workpiece, it stores energy in a spring, eventually releasing it as an impulse that drives the punch, producing the dimple. The impulse provided to the point of the punch is quite repeatable, allowing for uniform impressions to be made. History The patent history of automatic punches indicates two principal goals for the development of the tool: repeatability of impact, and convenience of operation. Other desirable properties include low recoil when triggered, ease of adjustment, and reliability. A number of designs for automatic center punches have been developed since the late 19th century as improvements over punches requiring the use of a striking tool. The earliest types were not fully automatic, using a captive weight lifted by the user or a s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molding (process)
Molding (American English) or moulding ( British and Commonwealth English; see spelling differences) is the process of manufacturing by shaping liquid or pliable raw material using a rigid frame called a mold or matrix. This itself may have been made using a pattern or model of the final object. A mold or mould is a hollowed-out block that is filled with a liquid or pliable material such as plastic, glass, metal, or ceramic raw material. The liquid hardens or sets inside the mold, adopting its shape. A mold is a counterpart to a cast. The very common bi-valve molding process uses two molds, one for each half of the object. Articulated molds have multiple pieces that come together to form the complete mold, and then disassemble to release the finished casting; they are expensive, but necessary when the casting shape has complex overhangs. Piece-molding uses a number of different molds, each creating a section of a complicated object. This is generally only used for larg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mirror Writing
Mirror writing is formed by writing in the direction that is the reverse of the natural way for a given language, such that the result is the mirror image of normal writing: it appears normal when reflected in a mirror. It is sometimes used as an extremely primitive form of cipher. A common modern usage of mirror writing can be found on the front of ambulances, where the word "AMBULANCE" is often written in very large mirrored text, so that drivers see the word the right way around in their rear-view mirror. It is also on Fire engine, fire engines and Police car, police cars too. Some people are able to produce handwritten mirrored text. Notably, Leonardo da Vinci wrote most of his personal notes in this way. Mirror writing calligraphy was popular in the Ottoman Empire, where it often carried mystical associations. Ability to write mirrored text An informal Australian newspaper experiment identified 10 true mirror-writers in a readership of 65,000. A higher proportion of left- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spring Pin
A spring pin (also called tension pin or roll pin) is a mechanical fastener that secures the position of two or more parts of a machine relative to each other. Spring pins have a body diameter which is larger than the diameter of the hole they are intended for, and a chamfer on either one or both ends to facilitate starting the pin into the hole. The spring action of the pin allows it to compress as it assumes the diameter of the hole. The force exerted by the pin against the hole wall retains it in the hole, therefore a spring pin is considered a self retaining fastener. Spring pins may be used to retain a shaft as a journal in a plain bearing, as a type of key to fasten one shaft to another, or to precisely fasten flat faces of mating parts together through symmetric hole locations. Types There are two types of spring pins: ''slotted spring pins'' and ''coiled spring pins''. Coiled spring pins A coiled spring pin, also known as a ''spiral pin'', is a self retaining enginee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roll Pin Punches
Roll may refer to: Physics and engineering * Rolling, a motion of two objects with respect to each-other such that the two stay in contact without sliding * Roll angle (or roll rotation), one of the 3 angular degrees of freedom of any stiff body (for example a vehicle), describing motion about the longitudinal axis ** Roll (aviation), one of the aircraft principal axes of rotation of an aircraft (angle of tilt to the left or right measured from the longitudinal axis) ** Roll (ship motion), one of the ship motions' principal axes of rotation of a ship (angle of tilt to the port or starboard measured from the longitudinal axis) * Rolling ''manoeuvre'', a manoeuvre of any stiff body (for example a vehicle) around its roll axis: ** Roll, an aerobatic maneuver with an airplane, usually referring to an aileron roll, but sometimes instead a barrel roll, rudder roll or slow roll ** Kayak roll, a maneuver used to right a capsized kayak ** Roll program, an aerodynamic maneuver performed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rivet
A rivet is a permanent mechanical fastener. Before being installed, a rivet consists of a smooth cylinder (geometry), cylindrical shaft with a head on one end. The end opposite the head is called the ''tail''. On installation, the deformed end is called the ''shop head'' or buck-tail. Because there is effectively a head on each end of an installed rivet, it can support Tension (physics), tension loads. However, it is much more capable of supporting Shear force, shear loads (loads perpendicular to the axis of the shaft). Fastenings used in traditional wooden boat building, such as copper nails and clinch bolts, work on the same principle as the rivet but were in use long before the term ''rivet'' was introduced and, where they are remembered, are usually classified among nails and bolts respectively. History Solid rivets are one of the oldest and most reliable types of fasteners, having been found in archeology, archaeological findings dating back to the Bronze Age. Rivet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drift Punch
In metalworking, a drift pin, drift pin punch, simply drift, is the name for a tool used for localizing a hammer blow. A drift is smaller in diameter than the hammer face, thus concentrating the force into a smaller area. A drift is also used where the surrounding surfaces need to be protected from the hammer blow. A drift is not used as a punch in the traditional sense of the term. Unlike most punches, force should never be applied to the tip of drift pin. Drifts are constructed from wood, light alloys, copper, or steel which are usually rods cut to size as for the job. Drifts can be used to remove dents from inaccessible places, for striking pins and keys out. Some drift pins are constructed with a taper, with the hammer acting on the large end of the taper. The tapered drift pin is used to align the two bolt holes in two separate components that are designed to mate. First the two components are maneuvered until the holes in each are in semi-alignment, such that the narr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taps And Dies
In the context of threading, taps and dies are the two classes of tools used to create screw threads. Many are cutting tools; others are forming tools. A tap is used to cut or form the female portion of the mating pair (e.g. a nut). A die is used to cut or form the male portion of the mating pair (e.g. a bolt). The process of cutting or forming threads using a tap is called ''tapping'', whereas the process using a die is called ''threading''. Both tools can be used to clean up a thread, which is called ''chasing''. However, using an ordinary tap or die to clean threads generally removes some material, which results in looser, weaker threads. Because of this, machinists generally clean threads with special taps and dies—called '' chasers''—made for that purpose. Chasers are made of softer materials and don't cut new threads. However they still fit tighter than actual fasteners, and are fluted like regular taps and dies so debris can escape. Car mechanics, for example, use ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Index Set
In mathematics, an index set is a set whose members label (or index) members of another set. For instance, if the elements of a set may be ''indexed'' or ''labeled'' by means of the elements of a set , then is an index set. The indexing consists of a surjective function from onto , and the indexed collection is typically called an ''indexed family'', often written as . Examples *An enumeration of a set gives an index set J \sub \N, where is the particular enumeration of . *Any countably infinite set can be (injectively) indexed by the set of natural numbers \N. *For r \in \R, the indicator function on is the function \mathbf_r\colon \R \to \ given by \mathbf_r (x) := \begin 0, & \mbox x \ne r \\ 1, & \mbox x = r. \end The set of all such indicator functions, \_, is an uncountable set indexed by \mathbb. Other uses In computational complexity theory and cryptography Cryptography, or cryptology (from "hidden, secret"; and ''graphein'', "to write", or ''-logy, -log ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Punch (transfer)
Punch commonly refers to: * Punch (combat), a strike made using the hand closed into a fist * Punch (drink), a wide assortment of drinks, non-alcoholic or alcoholic, generally containing fruit or fruit juice Punch may also refer to: Places * Punch, U.S. Virgin Islands * Poonch (other), often spelt as Punch, several places in India and Pakistan People * Punch (surname), a list of people with the name * Punch (nickname), a list of people with the nickname * Punch Masenamela (born 1986), South African footballer * Punch (rapper), 21st century American rapper Terrence Louis Henderson Jr. * Punch (singer), South Korean singer Bae Jin-young (born 1993) Arts, entertainment and media Fictional entities * Mr. Punch (also known as Pulcinella or Pulcinello), the principal puppet character in the traditional ''Punch and Judy'' puppet show * Mr. Punch, the masthead image and nominal editor of '' Punch'', largely borrowed from the puppet show * Mr. Punch, a fictional character in N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
