History of the Scales
Before the plastic model kit industry Hobbyists' scale models derive from those used by the firms which made the full-sized products. Originally, a "scale" was a physical measuring instrument, a notion which survives as concerns weight. First among scales are the rulers that are triangular in cross-section and called architect's scales or engineer's scales. The terminology used was of this manner: "scale size to full size", or the reverse. An architect's scale was used to make the first affordable models: doll houses and their furniture. Its popular scales for these miniatures were "one inch to the foot" and "one-half inch to the foot"; there is also "three-quarters inch to the foot".The proportion of the model to the prototype was originally called "size", as in "full-sized" or "half-sized", as used on a blueprint for making something that would fit on a workbench.Shipyards were the first to use the scales to make models of things larger than a house. The scales they used were expressed in a different manner: "one-foot-to-the-inch" through "six-feet-to-the-inch" were common. During the Second World War, battleship models were made "eight-foot-to-the-inch", in the later phrasing, "one-eighth-inch to the foot"; you will find these models used for training workers in maritime museums. The model ship would be referred to as "one-ninety-sixth size", or "1/96th", but rarely, as there were few scales commonly used; it couldn't possibly be "1/98th scale", for example.There were also rotary instruments in which one would line up marks on two dials to be able to translate measurements from units on the prototype to units on the model. After the production of kits to make plastic models became an industry, there were developed rulers marked in the model units and which are called scales.

Origins of the Plastic Model Kit
For aircraft recognition in the Second World War, the RAF selected making models to the scale of "one-sixth inch to the foot" (which was two British lines, a legal division of length which didn't make it to America, besides being a standard shipyard scale). Although some consumer models were sold pre-war in Britain to this scale, the airmens' models were pressed out of ground-up old rubber tires. This is of course the still-popular "one-seventy-second size".It wasn't predestined to succeed; there were competitors. The US Navy, in contrast, had metal models made to the proportion 1:432, which is "nine-feet-to-the-quarter-inch". At this scale, a model six feet away looked as the prototype would at about half a statute mile; and at seven feet, at about half a nautical mile.After the war, firms that moulded models from polystyrene entered the consumer marketplace, the American firm Revell notably offering a model of the Royal Coach around the time of the 1953 coronation. In the early years, firms offered models of aircraft and ships in "fit-the-box" size. A box that would make an impressive gift was specified, and a mould was crafted to make a model that wouldn't ludicrously slide around inside. Modellers could not compare models, nor switch parts from one kit to another. It was the British firm Airfix that brought the idea of the constant scale to the marketplace, and they picked the RAF's scale.In the 1960s, the company Monogram offered an aircraft actually labeled as ¼" scale, which may have been a common contraction in factories. They meant "one-quarter-inch to the foot", or "one-forty-eighth size". Shortly thereafter, hobbyists lost the ability to distinguish the two, and now the proportion is referred to as scale.

Model Aircraft
The premier scale for model aircraft vehicles is 1:72. Airliners are at 1:144, with a few at 1:288. A scale with more room for detail is 1:48. Other, arguably more luxurious, models are available at 1:32 and 1:24. A few First World War aircraft were offered at 1:28 by Aurora. Other scales which failed to catch on are 1:64, 1:96, and 1:128. Repressings of old moulds are often revived in these scales, however. There are also the most common carrier aircraft at the scales of their ships (see below). Although the Soviets did not supplant 1:48 with their scale 1:50, nor 1:32 with their scale 1:30, the Japanese tried to offer the scale 1:100. There is a major European project to bring about 1:150 to replace 1:144, just as they have small toy airliners in decimalized scales. And the French firm Heller SA, unlike any other in the world, offers models in the scale 1:125.

Model Rockets and Spacecraft
Model rocket kits began as a development of model aircraft kits, yet the scale of 1:72[V.close to 4mm.::1foot] never caught on. Scales 1:48 and 1:96 are used. There are some rockets of scales 1:128, 1:144, and 1:200, but Russian firms put their large rockets in 1:288. Heller is maintaining its idiosyncratic standard by offering some models in the scale of 1:125. Fantasy spacecraft, of course, can be of any scale, as they aren't going to be compared to anything on this planet.

Model Railways
An HO scale model railroadMain article: Rail transport modelling.
Model railways use the term "gauge", referring to the width of the tracks just as full-size railways do. Although railways were built to many gauges, generally it's the 'standard gauge', 4ft 8.5inch, that is referred to, as it is in this section. Meaning the distance between the inside vertical edge of opposing rails, gauges for model railways were originally in inches, but later they were standardized in metric units, even for companies which put models in traditional Architect's gauge proportions on such metric tracks. A range of scales were accepted by model railroaders for each gauge for mere convenience's sake.The most popular scale to go with a given gauge was often derived at by the following roundabout process. German artisans would take strips of metal of standard metric size to make things to blueprints whose dimensions were in inches: hence "4 mm to the foot" yields the 1:76.2 size of the "00 gauge". This British scale is anomalously used on the standard H0 gauge (16.5 mm) tracks, however, because early electric motor magnets were awkward in small 3.5mm/foot loco. models.The Germans have a more developed terminology, which can explain this a bit better. Baugrösse (English: "building size") is the alphanumeric designation, which has nothing to do with physical measuring. It's used for gauge, as in "No. 1 gauge", "HO gauge", or "Z gauge". Maßstab (English: "measure") is the proportion, with a colon, as in the corresponding terms "1:32", "1:87.1", and "1:220". Spurweite (English: "track width") is the distance between the tracks, or correspondingly "1¾-inch", "16.5 mm", and "6.5 mm", and again gauge is used for this in English. One might add to these the old use of the term scale, of "3/8 inch to the foot" and "3.5 mm to the foot" for the first two, while the last really isn't expressible in this manner. Early 1900s German mass-produced toys had a measured gauge from rail centre to rail centre of rolled tinplate rail, with much latitude between flange & rail.There are three different standards for the "0" Gauge, each of which uses tracks of 32 mm for the standard gauge. The American version continues a dollhouse scale of 1:48. It is sometimes called "quarter-gauge", as in "one-quarter-inch to the foot". The British version continued the pattern of subcontracting to Germans; so, at 7 mm to the foot, it works out to a scale of 1:43.5. Later, MOROP, the European authority of model railroad firms, declared that the "0" gauge (still 32 mm) must use the scale of 1:45. That is, in Europe the below-chassis dimensions have to be slightly towards 4ft. 6 inches, to allow wheel/tyre/splasher clearance for smaller than realistic curved sections."Live steam" railways, that you actually ride on, are built in many scales, such as 1-1/2", 1", and 3/4" to the foot. Common gauges are 7-1/2" (Western US) and 7-1/4" (Eastern US & rest of the world), 5", 4-3/4". Smaller Live Steam gauges do exist, but are hardly "rideable".

Model Cars
Although the British scale for "O" gauge was first used for model cars comprised of rectilinear and circular parts, it was the origin of the European scale for cast or injection moulded model cars. MOROP's specification will not alter the series of cars in 1:43 scale, as it has the widest distribution in the world.In America, a series of cars was developed from at first cast metal and later styrene models ("promos") offered at new-car dealerships to drum up interest. The firms AMT, Revell, and Monogram produced them in a scale derived from the Architect's scale: 1:24. Other firms used 1:25. Some cars are also made in 1:32 scale, and rolling toys are often made on the scale 1:64.

Model Robots
Japanese firms have marketed toys and models of what are often called mecha, nimble humanoid fighting robots. Model robots are marketed in scales 1:100 and 1:144, like model aircrafts, which seems strange to some westerners as they believe that they are best displayed in scenes crashing against houses, and thus should use natural model railway gauges instead. Still, as there are 1:144 model railways, in Japan itself this do not matter much; and numerous after market accessories for mecha models (as well as scratch building, which is what makes this hobby fun) render this "strange" scaling matter little.Usually, they do not require glue or paint (snapped together), though when they are used will greatly enhance the look of the model.Due to the fact that mechas are not real objects, and is humanoid, aside from aiming at realism, it may also aim for pure creativity, either on creating an entire new look of the model, or strike artistic poses. Thus, scratchbuilding for Gunpla is actually quite common.

Model Tanks and Wargaming
Just before the twentieth century, the British historian (and science fiction author and forgotten mainstream novelist) H. G. Wells published a book, Little Wars, on how to play at battles in miniature. His books use 54mm lead figures, particularly those manufactured by Britains. His fighting system revolved around the use of spring-loaded model guns which shot matchsticks. This use of physical mechanisms was echoed in the later games of Fred Jane, whose rules required throwing darts at ship silhouettes; his collection of data on the world's fleets was later published and became renowned. Dice have largely replaced this toy mayhem for consumers.For over a century, toy soldiers were made of white metal, a lead-based alloy, often in Architect's scale-based ratios in the English-speaking countries, and called tin soldiers. After the Second World War, such toys were on the market for children but now made of a safe plastic softer than styrene. American children called these "army men". Many sets were made in the new scale of 1:40. A few styrene model kits of land equipment were offered in this and in 1:48 and 1:32 scales. However, these were swept away by the number of kits in the scale of 1:35.Those who continued to develop miniature wargaming preferred smaller scale models, the soldiers still made of soft plastic. Airfix particularly wanted people to buy 1:76 scale soldiers and tanks to go with "00" gauge train equipment. Roco offered 1:87 scale styrene military vehicles to go with "H0" gauge model houses. However, although there isn't any 1:72 scale model railroad, more toy soldiers are now offered in this scale because it is the same as the popular aircraft scale. The number of fighting vehicles in this scale is also increasing, although the number of auxiliary vehicles available is far fewer than in 1:87 scale.Armies use smaller scales still. The US Army specifies models of the scale 1:285 for its "sand-table" wargaming. There are metal ground vehicles and helicopters in this scale, which is a near -rationalization of a notion of"one-quarter-inch-to-six-feet". The continental powers of NATO have developed the similar scale of 1:300, even though metric standardizers really don't like any divisors other than factors of 10, 5, and 2, so maps are not commonly offered in Europe in scales with a "3" in the denominator.Consumer wargaming has since expanded into fantasy realms, employing scales large enough to be painted in imaginative detail - so called "heroic" 28mm figures, (roughly 1:64, or S scale). Firms which produce these do so in so small production lots that they are necessarily made of white metal. And the quite successful British firm Games Workshop even offers plastic fantasy war machines, like Warhammer 40,000.

Model Buildings
Other than as an adjunct to model railroading or in forming dioramas with model war machines, this has not caught on as a hobby. So the expected standardized sizes from architectural practise have not developed. Hence Heller can offer a model of the Eiffel tower at the unique scale of 1:650, which couldn't be compared to anything.

Model Ships and Naval Wargaming
Just before the Second World War, the American naval historian (and science fiction author) Fletcher Pratt published a book on naval wargaming as could be done by civilians using ship models cut off at the waterline to be moved on the floors of basketball courts and similar locales. The scale he used was very strange (maybe 1:550), but as the hobby progressed, it was progressively replaced by the series 1:600, 1:1200, and 1:2400. These had the advantage of approximating the nautical mile as 120 inches, 60 inches, and 30 inches, respectively. As the knot is based on this mile and a 60-minute hour, this was quite handy.After the war, firms emerged to produce models from the same white metal used to make toy soldiers. One British firm offered a tremendously wide line of merchant ships and dockyard equipment in the scale 1:1200.A prestige scale for boats, comparable to that of 1:32 for fighter planes, is 1:72, producing huge models. For the smaller ships, kits are offered in the traditional shipyard scales of 1:96, 1:108, or 1:192. Airfix makes full-hull models in the scale which the Royal Navy has used to compare the relative sizes of ships: 1:600. Monogram makes some kits to half the scale of the US Army standard: 1:570.Some American and foreign firms have made models in a proportion from the Engineer's scale: "one-sixtieth-of-an-inch-to-the-foot", or 1:720.But the continental Europeans have an on-going project of getting rid of all conversions and measurements which they consider non-standard. As they saw how four Japanese model-making firms (Tamiya, Hasegawa, Aoshima, and Fujimi) formed a cartel to apportion out the project of putting out waterline kits of the whole fleet of Japanese warships of the Second World War on the market in a proportion that no firm from any other country did - 1:700, the Europeans are attempting to have the scale of 1:400 standardized for full-hull model ships, even though some Japanese firms have produced larger ships in the luxury scale of 1:350. And in scales more conducive to wargaming, Europeans are now marketing waterline kits in the scales 1:1250 and 1:2500 to supplant the British and American lines. The Chinese are joining them. Such trends toward standardization has not affected the Japanese firm Nichimaco, which still produces fit-in-the-box sizes from old molds, and 1:450

Static Model Aircraft
Static model aircraft, those not intended to fly, are commonly built using plastic detail parts, photo etched brass, and wire, though other materials such as wood, metal, and paper are also often used. Some static models are scaled for use in wind tunnels, where the data acquired is used to aid the design of full scale aircraft.

Models
Can be bought already built and painted, as well as models that require construction, painting and gluing, or snap fit models (most of which come with decals or paint already applied)The collector can choose from plastic and diecast military and commercial helicopters and planes; and for the less skilled collector, snap together military and commercial planes. Snap models are becoming increasingly popular because of their ease of construction.Plastic model plane manufacturers include Revell who are generally recognized as the most popular manufacturer of plane models in the US, Airfix, whose name is synonymous with the hobby in the UK, Hobbycraft, DML, Frog, Matchbox, Minicraft and Hasegawa, Tamiya and Testors. The peak of the plastic modelling hobby was most probably the 1970s, and while it is still very popular today, at that time the hobby could support a considerable number of competing, large companies. During the 1980s, many of them were forced to radically downsize, restructure, merge, or go out of business. Some attribute this to the rise of computer games over the more traditional type of hobbies. Another consideration is that kits have generally required considerable skill and patience to achieve good results, and that ready-made or more quickly constructed models have taken over the market for those simply looking for a toy to play with.Plastic scale model aircraft kits usually come in standard scales such as 1/144, 1/72, 1/48 (also known as quarter-scale), and 1/32. This scale indicates the relationship between the size of the model and the size of the actual aircraft. For example, in 1/48 scale, 1 mm on the model represents 48 mm on the actual aircraft. One of the most expensive airplane models in the world, that of a Boeing 707 made in the 1/10 scale, is valued at US$18,000.Due to the prohibitive costs of producing molded plastic models, there are relatively few manufacturers of injection-molded plastic models. Smaller manufacturers primarily produce models of lesser-known subjects, or accessories to enhance mainstream kits. In order to avoid large costs, small manufacturers cut production costs by producing kits using lower-quality moldings, vacuformed plastic, or resin casting.Die-Cast model plane manufacturers include Dyna-Flytes (recognized as the first manufacturer of that type of model), Schabak, Gemini Jets and Herpa Wings.=Snap Fit plastic plane models include Wooster, Long Prosper (In South Africa, Long & Prosper), and Flight Miniatures of Cottonwood, Arizona.Vacuum formed kits are generally for the more skilled collector and are manufactured by small companies such as Koster Aero Enterprises. Specialized kits cast in resin are also available.

Scale Plane Models
Made from heavy paper or card stock. Several card model kit companies exist, smaller even than Vacuum formed manufacturers, among them being ModelArt, Halinski, Modelik, JSC and FlyModel. Many card models are also distributed through the internet, and several are offered this way free of charge. Card model kits are also not limited to just airplanes. Such kits are available for all types of vehicles, buildings, computers, firearms, even animals.Most of the world's airlines allow their fleet aircraft to be modelled as a form of publicity, some of the most notable being Delta Air Lines, Air France, British Airways, Aerolíneas Argentinas, Avianca, Aeroméxico, Fed Ex, Polar Air Cargo, Air New Zealand, Qantas, China Airlines, South African Airways, Finnair, and Royal Jordanian.

Flying Model Aircraft
Miniature 15 gram aircraft by Prof. Jean-Daniel NicoudFlying models are usually what is meant by the term aeromodelling.

Free Flight
The essence of free flight model aircraft is that their flight path is pre-programmed, and once released, they are not directly controlled by the operator. When flown competitively, the usual aim is to launch the model into rising air, and to fly for the maximum time. To accomplish this, free flight models (except indoor models) tend to be designed for two very different flying modes: climbing rapidly and slowly circling with minimum fall rate. The climb can be under power, driven by momentum or under tow. Much of the challenge in designing and flying these is to maintain aerodynamic stability in both modes and to make a smooth transition.

Control line
A simple way of controlling a flying model aircraft. The aircraft is connected to the operator by a set of wires, which work the elevator of the model. This allows the model to be controlled in the pitch axis. It is constrained to fly on the surface of a hemisphere by the control wires.

Construction
Flying models have to be designed according to the same principles as full-sized aircraft, and therefore their construction is very different from most static models. Flying models borrow construction techniques from vintage full-sized aircraft (although models rarely use metal structures.) These might consist of forming the frame of the model using thin strips of light wood such as balsa, then covering it with fabric and subsequently doping the fabric to form a light and sturdy frame which is also airtight. For very light models, very thin paper can be substituted for fabric. Or, heat-curing plastic films ("heat shrink covering" or "solarfilm") can be ironed on - a hand-held iron causes the film to shrink and adhere to the frame. A hair dryer can also be used.

Powered Models
Powered models contain an onboard powerplant to propell the aircraft through the air.

Old and Cold
An old method of powering free flight models is Alphonse Pénaud's elastic motor, essentially a long rubber band that is wound up prior to flight. It is the most widely used powerplant for model aircraft, found on everything from children's toys to serious competition models. The elastic motor offers extreme simplicity and survivability, but suffers from limited running time, an exponential reduction of thrust over the motor's operational cycle, and it places substantial stress on the fuselage. Stored compressed gas (CO2), similar to filling a balloon and then releasing it, also powers simple models. A more sophisticated use of compressed CO2 is to power a piston expansion engine, which can turn a large, high pitch prop. These engines can incorporate speed controls and multiple cylinders, and are quite capable of powering ligthtweight scale radio control aircraft. Gasparin and Modella are two current makers of CO2 engines. Rubber and CO2 are known as "cold" power because they become cooler when running, rather than hotter as combustion engines and batteries. Thermodynamically, this means that both store negative entropy, rather than energy, and extract heat energy from the surrounding environment.

Steam, which is even older than rubber power, and like rubber, contributed much to Aviation history, is now rarely used.

Solid Modelling
Solid modelling (or modeling) is the unambiguous representation of the solid parts of an object, that is, models of solid objects suitable for computer processing. It is also known as volume modelling. Other modelling methods include surface models (used extensively in automotive and consumer product design as well as entertainment animation) and wire frame models (which can be ambiguous about solid volume).Primary uses of solid modelling are for CAD, engineering analysis, computer graphics and animation, rapid prototyping, medical testing, product visualization and visualization of scientific research.

Feature Based Modelling
Complex combinations of objects and operators are considered together as a unit which can be modified or duplicated. Order of operations is kept in a history tree, and parametric changes can propagate through the tree.

Model Car
A model car is a toy which represents an automobile, generally reproducing the shapes of actually produced vehicles, as a small scale model.Model car most frequently refers to scale miniatures of real production vehicles, designed as kits for the enthusiast to construct. They can be created in plastic, die-cast metal, resin, even wood. The best kits have incredible levels of detail, even in parts unseen when the finished model is on display. Major manufacturers are AMT, Revell, and Monogram, but many smaller companies abound.

History
The model kit car hobby began in the early 1950s, as an outgrowth of promotional models manufactured for automobile dealers. Youngsters would be given the scale models to play with while the parents and the salesman haggled. Collecting and trading these "promos" soon became a popular hobby.During the 1950s and 1960s, intrest in the hobby peaked, as many comanies started up to profit from the interest in the pormo cars. AMT, Revell and Monogram started up during this time, and it was considered a "golden age" for model kit cars.Interest in model cars began to wane in the mid-1970s as a result of builders growing older and moving on to other pursuits. By the early 1980s, model building had been largely replaced by video gaming as a favorite pastime of American youth.A resurgence was experience in the late 1980s, due to many who been involved in the hobby in past years rediscovering it. Monogram helped spark the revival with a series of replicas of NASCAR race cars, as did AMT with a kit of the 1966 Chevrolet Nova, which modelers had been requesting for years.

Japanese Model Kit Manufacturers
Tamiya, Fujimi and Hasegawa, among them - also stepped up their presences in the U.S. market during the 1980s and 1990s. While many of their car kits have limited appeal to American modelers raised on "Detroit iron," the quality of their products is perhaps the finest in the industry.Some toys which mimic production vehicles qualify as model cars. These are generally sold complete, needing no construction by the consumer.

Radio Control Model Cars
A radio controlled car is a powered model car driven from a distance by a hand-held radio transmitter which sends its control information to the car's onboard radio receiver. Building, driving, and modifying radio-controlled car kits is a hobby enjoyed by enthusiasts of all ages.

Types of Cars
Radio controlled (or R/C) cars can be categorized in two ways, electric powered and gas powered. Electric cars use small but powerful electric motors and rechargeable nickel-cadmium, nickel metal hydride, or lithium polymer cells to power them. Some radio controlled cars use small internal combustion engines fuelled by a special mixture of nitromethane, methanol, and oil (either castor oil or synthetic oil), which are referred to as "gas" cars. Recently, exceptionally large models have been introduced that are powered by small gasoline engines. Electric cars are generally considered easier for the novice to work with than fuel-driven models, but can be equally as complex at the higher budget and skill levels.In both of these categories, both on-road and off-road vehicles are available. Off-road models, which are built with fully-functional off-road suspensions, can be used on various types of terrain. In comparison, on-road cars, which generally have a limited or non-existent suspension, are strictly limited to smooth, paved surfaces.

Mecha
In some works of science fiction, mecha (singular or plural, less frequently meka) or mechs (singular: mech) (sometimes referred to as giant robots) are piloted or remote-controlled limbed vehicles. The key difference between mecha and robots (in the English usage of these terms) is that a mecha has a pilot or controller. The term is derived from the Japanese abbreviation for the English term "mechanical", although English speakers have repurposed the term to mean only the vehicles described above. The original Japanese term of mecha has the broader denotation of all mechanical objects, including cars, guns, computers, and other objects without pilots or limbs.Mecha are generally war machines, sometimes mass-produced, and are seen as a component of a whole military body and do not act alone in their conflicts, although it is common that only mecha fight mecha, much in the same way tanks and fighter planes do, even in large scale battles.A large, bipedal machine is not the most flexible of designs, and aside from occasional use in things like heavy construction work, mecha are most often built for combat purposes. As such, their status varies widely between different settings, from one type of unit among others to the undisputed rulers of the battlefield.The distinction between smaller mecha and their smaller cousins (and likely progenitors), the powered armor suits, is blurred; according to one definition, a mecha is piloted while a powered armor is worn. Anything large enough to have a cockpit where the pilot is seated is generally considered a mecha.The first occurrence of mecha in fiction is thought to be the novel The War of the Worlds by H. G. Wells where the Martians use tripod walkers very similar to mecha.Rarely, mecha has been used in a fantasy convention, most notably in The Vision of Escaflowne and Maze animes. In those cases, the mecha designs are usually based on some alternative steampunk technology or 'lost' science-fiction technology from ancient times.

Model Rocket
Model rocketry is a hobby similar to model airplanes. In the contemporary U.S., there are two distinct types of rocket hobbyist.

Amateur Rocketry
Amateur rocketry hobbyists experiment with fuels and make their own rocket motors, often launching rockets hundreds of miles out to sea. Amateur rockets can be dangerous because noncommercial rocket motors fail more often than commercial rocket motors. Amateur rocketry was an especially popular hobby in the late 1950s, following the launch of Sputnik. An appalling accident rate led individuals such as G. Harry Stine and Vernon Estes to make model rocketry a safe and widespread hobby. The National Association of Rocketry Safety Code is provided with most rocket kits and engines.