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Gate Mark
A sprue is a large diameter vertical channel through which liquid material is introduced into a mold. It connects the pouring basin to the runner. In many cases it controls the flow of material into the mold. During casting or molding, the material in the sprue will solidify and need to be removed from the finished part. It is usually tapered downwards to minimize turbulence and formation of air bubbles. Casting In casting, a sprue is the passage through which a molten material is introduced into a mold, and the term also refers to the excess material which solidifies in the sprue passage. Function Sprues can serve as filters, as heat sinks, and as feeders. Bronze, in particular, has a high shrinkage rate as it is cooling. A sprue is tapered with its bigger end at the top to receive the liquid metal, the smaller end is connected to the runner. Sprue design The design of the sprue gating and runner is also essential for casting. The design can incorporate either bottom or ver ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scale Model
A scale model is a physical model that is geometrically similar to an object (known as the ''prototype''). Scale models are generally smaller than large prototypes such as vehicles, buildings, or people; but may be larger than small prototypes such as anatomical structures or subatomic particles. Models built to the same scale as the prototype are called '' mockups''. Scale models are used as tools in engineering design and testing, promotion and sales, filmmaking special effects, military strategy, and hobbies such as rail transport modeling, wargaming and racing; and as toys. Model building is also pursued as a hobby for the sake of artisanship. Scale models are constructed of plastic, wood, or metal. They are usually painted with enamel, lacquer, or acrylics. Model prototypes include all types of vehicles (railroad trains, cars, trucks, military vehicles, aircraft, and spacecraft), buildings, people, and science fiction themes (spaceships and robots). Methods M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chvorinov's Rule
Chvorinov's rule is a physical relationship that relates the solidification time for a simple casting to the volume and surface area of the casting. It was first expressed by Czech engineer Nicolas Chvorinov in 1940. Description According to the rule, a casting with a larger surface area and smaller volume will cool more quickly than a casting with a smaller surface area and a larger volume under otherwise comparable conditions. The relationship can be mathematically expressed as: :t = B \left( \frac \right)^n Where is the solidification time, is the volume of the casting, is the surface area of the casting that contacts the mold, is a constant, and is the mold constant. This relationship can be expressed more simply as: :t = BM^n Where the modulus is the ratio of the casting's volume to its surface area: : M = \frac The mold constant depends on the properties of the metal, such as density, heat capacity, heat of fusion and superheat, and the mold, such as initial t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greeble
Greebles, also called greeblies (singular: greebly) or nurnies, are small relief details used to give visual complexity to a model. The act of decorating a model with greebles is known as greebling. While greebling originated as a technique in filmmaking, it is commonly used in model-making, toy design, and kitbashing. The term "greeblies" was coined by George Lucas in the 1970s to describe details on model ships used in the production of ''Star Wars (film), Star Wars''. Ron Thornton (visual effects designer), Ron Thornton is credited with coining the term "nurnies" to refer to CGI technical detail that his company Foundation Imaging produced for the ''Babylon 5'' series, while the model-making team of ''2001: A Space Odyssey (film), 2001: A Space Odyssey'' referred to them as "wiggets". In science-fiction model design, greebles are used to imply mechanical function without necessarily having any real purpose. They may also serve to create an illusion of scale. In the production ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Model Airplane
A model aircraft is a physical model of an existing or imagined aircraft, and is built typically for display, research, or amusement. Model aircraft are divided into two basic groups: flying and non-flying. Non-flying models are also termed static, display, or shelf models. Aircraft manufacturers and researchers make wind tunnel models for testing aerodynamic properties, for basic research, or for the development of new designs. Sometimes only part of the aircraft is modelled. Static models range from mass-produced toys in white metal or plastic to highly accurate and detailed models produced for museum display and requiring thousands of hours of work. Many are available in kits, typically made of injection-molded polystyrene or resin. Flying models range from simple toy gliders made of sheets of paper, balsa, card stock or foam polystyrene to powered scale models built up from balsa, bamboo sticks, plastic, (including both molded or sheet polystyrene, and styrofoam), me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antenna (radio)
In radio-frequency engineering, an antenna (American English) or aerial (British English) is an electronic device that converts an alternating current, alternating electric current into radio waves (transmitting), or radio waves into an electric current (receiving). It is the interface between radio waves Radio propagation, propagating through space and electric currents moving in metal Electrical conductor, conductors, used with a transmitter or receiver (radio), receiver. In transmission (telecommunications), transmission, a radio transmitter supplies an electric current to the antenna's Terminal (electronics), terminals, and the antenna radiates the energy from the current as electromagnetic radiation, electromagnetic waves (radio waves). In receiver (radio), reception, an antenna intercepts some of the power of a radio wave in order to produce an electric current at its terminals, that is applied to a receiver to be amplifier, amplified. Antennas are essential components ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Model Ship
Ship models or model ships are scale models of ships. They can range in size from 1/6000 scale wargaming miniatures to large vessels capable of holding people. Ship modeling is a craft as old as shipbuilding itself, stretching back to ancient times when water transport was first developed. History Ancient Mediterranean Ancient ship and boat models have been discovered throughout the Mediterranean, especially from ancient Greece, Egypt, and Phoenicia. These models provide archaeologists with valuable information regarding seafaring technology and the sociological and economic importance of seafaring. In spite of how helpful ancient boat and ship models are to archaeologists, they are not always easily or correctly interpreted due to artists’ mistakes, ambiguity in the model design, and wear and tear over the centuries. Ships "were among the most technologically complex mechanisms of the ancient world." Ships made far-flung travel and trade more comfortable and economi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Model Maker
A Model maker is a professional Craftsperson who creates a three-dimensional representation of a design or concept. Most products in use and in development today first take form as a model. This "model" may be an exacting duplicate (prototype) of the future design or a simple mock-up of the general shape or concept. Many prototype models are used for testing physical properties of the design, others for usability and marketing studies. Mock-ups are generally used as part of the design process to help convey each new iteration. Some model makers specialize in "scale models" that allow an easier grasp of the whole design or for portability of the model to a trade show or an architect or client's office. Other scale models are used in museum displays and in the movie special effects industry. Model makers work in many environments from private studio/shops to corporate design and engineering facilities to research laboratories. The model maker must be highly skilled in the use of man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Razor Saw
A backsaw is any hand saw which has a stiffening rib on the edge opposite the cutting edge, enabling better control and more precise cutting than with other types of saws. Backsaws are normally used in woodworking for precise work, such as cutting dovetails, mitres, or tenons in cabinetry and joinery. Because of the stiffening rib, backsaws are limited in the depth to which they can cut. Backsaws usually have relatively closely spaced teeth, often with little or no set. Types of backsaws Backsaws include the tenon saw, the dovetail saw, and the (United Kingdom) sash saw 1. Tenon and dovetail saws usually have a pistol grip style handle which may be open or closed at the bottom. Different types of backsaw include: * Mitre saw – often referred to as a large backsaw (20–30 inches or 60–90 cm) used either in a wooden or metal mitre box or in a metal frame which allowed cutting mitres of any specified angle. Note that not all mitre saws are backsaws, and the electri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Craft Knife
A utility knife is any type of knife used for general manual work purposes.Peterson, Harold L., ''Daggers and Fighting Knives of the Western World'', London: Herbert Jenkins Ltd., , p. 1 Such knives were originally fixed-blade knives with durable cutting edges suitable for rough work such as cutting cordage, cutting/scraping hides, butchering animals, cleaning fish scales, reshaping timber, and other tasks. Craft knives are small utility knives used as precision-oriented tools for finer, more delicate tasks such as carving and papercutting. Today, the term "utility knife" also includes small folding-, retractable- and/or replaceable-blade knives suited for use in the general workplace or in the construction industry. The latter type is sometimes generically called a Stanley knife, after a prominent brand designed by the American tool manufacturing company Stanley Black & Decker. There is also a utility knife for kitchen use, which is sized between a chef's knife and pari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Die (manufacturing)
A die is a specialized machine tool used in manufacturing industries to cut and/or Forming (metalworking), form material to a desired shape or profile. ''Stamping (metalworking), Stamping dies'' are used with a machine press, press, as opposed to ''Draw plate, drawing dies'' (used in the manufacture of wire) and ''Die casting, casting dies'' (used in Molding (process), molding) which are not. Like molds, dies are generally customized to the item they are used to create. Products made with dies range from simple paper clips to complex pieces used in advanced technology. Continuous production, Continuous-feed laser cutting may displace the analogous die-based process in the automotive industry, among others. Die stamping Blanking and piercing are two Shearing (manufacturing), die cutting operations, and Bending (metalworking), bending is an example of a die forming operation. Die forming Forming operations work by deforming materials like sheet metal or plastic using force (Compre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Casting
Casting is a manufacturing process in which a liquid material is usually poured into a mold, which contains a hollow cavity of the desired shape, and then allowed to solidify. The solidified part is also known as a casting, which is ejected or broken out of the mold to complete the process. Casting materials are usually metals or various time setting materials that cure after mixing two or more components together; examples are epoxy, concrete, plaster and clay. Casting is most often used for making complex shapes that would be otherwise difficult or uneconomical to make by other methods. Heavy equipment like machine tool beds, ships' propellers, etc. can be cast easily in the required size, rather than fabricating by joining several small pieces. Casting is a 7,000-year-old process. The oldest surviving casting is a copper frog from 3200 BC. History Throughout history, metal casting has been used to make tools, weapons, and religious objects. Metal casting history and develo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
