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93-407: A frisbee (pronounced / ˈ f r ɪ z b iː / FRIZ -bee ), also called a flying disc or simply a disc , is a gliding toy or sporting item that is generally made of injection-molded plastic and roughly 20 to 25 centimetres (8 to 10 in) in diameter with a pronounced lip. It is used recreationally and competitively for throwing and catching, as in flying disc games . The shape of

186-404: A cavity perpendicular to the draw direction, to form overhanging part features. When the mould is opened, the slides are pulled away from the plastic part by using stationary “angle pins” on the stationary mould half. These pins enter a slot in the slides and cause the slides to move backward when the moving half of the mould opens. The part is then ejected and the mould closes. The closing action of

279-547: A certain velocity in flight. The term frisbee is often used generically to describe all flying discs , but Frisbee is a registered trademark of the Wham-O toy company. This protection results in organized sports such as ultimate or disc golf having to forgo use of the word "Frisbee". Frisbees were invented in the late 1930s by the American inventor Walter Frederick Morrison . Morrison and his future wife Lucile had fun tossing

372-784: A diameter of 10 inches (25 cm) or less and a weight of around 160 grams (5.6 oz), but this is subject to change according to the performer's need. The IFT guts competitions in Northern Michigan, the Canadian Open Frisbee Championships (1972), Toronto, Ontario, the Vancouver Open Frisbee Championships (1974), Vancouver, British Columbia, the Octad (1974), New Jersey, the American Flying Disc Open (1974), Rochester, New York, and

465-566: A different colour, is injection-moulded into those spaces. Pushbuttons and keys , for instance, made by this process have markings that cannot wear off, and remain legible with heavy use. Manufacturers go to great lengths to protect custom moulds due to their high average costs. The perfect temperature and humidity level is maintained to ensure the longest possible lifespan for each custom mould. Custom moulds, such as those used for rubber injection moulding, are stored in temperature and humidity controlled environments to prevent warping. Tool steel

558-523: A flexible polypropylene plastic by Southern California Plastics, the original molder. He discovered that he could produce his own disc more cheaply, and he designed a new model in 1955 called the Pluto Platter, the archetype of all modern flying discs. He sold the rights to Wham-O on January 23, 1957. In June 1957, Wham-O co-founders Richard Knerr and Arthur "Spud" Melin gave the disc the brand name "Frisbee" after learning that college students were calling

651-402: A flying disc in the opposing court. Dogs and their human flying disc throwers compete in events such as distance catching and somewhat choreographed freestyle catching. This is a precision and accuracy sport in which individual players throw a flying disc at a target pole hole. In 1926, In Bladworth, Saskatchewan, Canada, Ronald Gibson and a group of his Bladworth Elementary school chums played

744-575: A game using metal lids, they called "Tin Lid Golf". In 1976, the game of disc golf was standardized with targets called "pole holes" invented and developed by Wham-O's Ed Headrick. In 1974, freestyle competition was created and introduced by Ken Westerfield and Discraft 's Jim Kenner. Teams of two or three players are judged as they perform a routine that consists of a series of creative throwing and catching techniques set to music. A half-court disc game derived from ultimate, similar to hot box. The object

837-467: A hopper into a heated barrel with a reciprocating screw. Upon entrance to the barrel, the temperature increases and the Van der Waals forces that resist relative flow of individual chains are weakened as a result of increased space between molecules at higher thermal energy states. This process reduces its viscosity , which enables the polymer to flow with the driving force of the injection unit. The screw delivers

930-483: A host of materials mainly including metals (for which the process is called die-casting ), glasses , elastomers , confections , and most commonly thermoplastic and thermosetting polymers. Material for the part is fed into a heated barrel, mixed (using a helical screw), and injected into a mould cavity , where it cools and hardens to the configuration of the cavity. After a product is designed, usually by an industrial designer or an engineer , moulds are made by

1023-433: A large variation in dimensions from cycle-to-cycle. More commonly used now is scientific or decoupled moulding, a method pioneered by RJG Inc. In this the injection of the plastic is "decoupled" into stages to allow better control of part dimensions and more cycle-to-cycle (commonly called shot-to-shot in the industry) consistency. First the cavity is filled to approximately 98% full using velocity (speed) control. Although

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1116-492: A material hopper, an injection ram or screw-type plunger, and a heating unit. Also known as platens, they hold the moulds in which the components are shaped. Presses are rated by tonnage, which expresses the amount of clamping force that the machine can exert. This force keeps the mould closed during the injection process. Tonnage can vary from less than 5 tons to over 9,000 tons, with the higher figures used in comparatively few manufacturing operations. The total clamp force needed

1209-502: A mould-maker (or toolmaker) from metal , usually either steel or aluminium , and precision-machined to form the features of the desired part. Injection moulding is widely used for manufacturing a variety of parts, from the smallest components to entire body panels of cars. Advances in 3D printing technology, using photopolymers that do not melt during the injection moulding of some lower-temperature thermoplastics, can be used for some simple injection moulds. Injection moulding uses

1302-554: A new plastic layer to form around the first part. This is often referred to as overmoulding. This system can allow for production of one-piece tires and wheels. Moulds for highly precise and extremely small parts from micro injection molding requires extra care in the design stage, as material resins react differently compared to their full-sized counterparts where they must quickly fill these incredibly small spaces, which puts them under intense shear strains. Two-shot, double-shot or multi-shot moulds are designed to "overmould" within

1395-471: A popcorn can lid after a Thanksgiving Day dinner in 1937. They soon discovered a market for a light-duty flying disc when they were offered 25 cents (equivalent to $ 5 in 2023) for a cake pan that they were tossing back and forth on a beach near Los Angeles . In 2007, in an interview in The Virginian-Pilot newspaper, Morrison compared that with the 5 cents (equivalent to $ 1 in 2023) it cost at

1488-404: A single moulding cycle and must be processed on specialised injection moulding machines with two or more injection units. This process is actually an injection moulding process performed twice and therefore can allow only for a much smaller margin of error. In the first step, the base colour material is moulded into a basic shape, which contains spaces for the second shot. Then the second material,

1581-410: A small shot weight and fills gradually until the mould is 95 to 99% full. Once they achieve this, they apply a small amount of holding pressure and increase holding time until gate freeze off (solidification time) has occurred. Gate freeze off time can be determined by increasing the hold time, and then weighing the part. When the weight of the part does not change, the gate has frozen and no more material

1674-422: A solidified thermoset component. After the part has solidified, valves close to isolate the injection system and chemical precursors , and the mould opens to eject the moulded parts. Then, the mould closes and the process repeats. Pre-moulded or machined components can be inserted into the cavity while the mould is open, allowing the material injected in the next cycle to form and solidify around them. This process

1767-406: A special-purpose machine that has three parts: the injection unit, the mould and the clamp. Parts to be injection-moulded must be very carefully designed to facilitate the moulding process; the material used for the part, the desired shape and features of the part, the material of the mould, and the properties of the moulding machine must all be taken into account. The versatility of injection moulding

1860-418: A timely manner, chemical crosslinking may occur causing the screw and check valves to seize and potentially damaging the injection moulding machine. Injection moulding consists of the high pressure injection of the raw material into a mould, which shapes the polymer into the desired form. Moulds can be of a single cavity or multiple cavities. In multiple cavity moulds, each cavity can be identical and form

1953-476: Is 38–45 on the Rockwell-C scale . Hardened steel moulds are heat treated after machining; these are by far superior in terms of wear resistance and lifespan. Typical hardness ranges between 50 and 60 Rockwell-C (HRC). Aluminium moulds can cost substantially less, and when designed and machined with modern computerised equipment can be economical for moulding tens or even hundreds of thousands of parts. Beryllium copper

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2046-469: Is a function of the resin being used, and can be relatively predictable. To prevent spikes in pressure, the process normally uses a transfer position corresponding to a 95–98% full cavity where the screw shifts from a constant velocity to a constant pressure control. Often injection times are well under 1 second. Once the screw reaches the transfer position the packing pressure is applied, which completes mould filling and compensates for thermal shrinkage, which

2139-488: Is by David Wiggins Jr. with a distance of 338 metres (1,109 ft). Disc dog sports use relatively slow-flying discs made of more pliable material to better resist a dog's bite and prevent injury to the dog. Flying rings are also available which typically travel significantly farther than any traditional flying disc. Illuminated discs are made of phosphorescent plastic or contain chemiluminescent fluid or battery-powered LEDs for play after dark. Others whistle when they reach

2232-412: Is dealt with in the next section.}) Some extremely high production volume moulds (like those for bottle caps) can have over 128 cavities. In some cases, multiple cavity tooling moulds a series of different parts in the same tool. Some toolmakers call these moulds family moulds, as all the parts are related—e.g., plastic model kits. Some moulds allow previously moulded parts to be reinserted to allow

2325-459: Is described in the song "Friz Me the Frisby," as a Frisbee was passed among stooges in the audience. The scene was expressly intended as a way to introduce the game to the audience. In 1964, Ed Headrick was hired as Wham-O's general manager and vice president of marketing. Headrick redesigned the Pluto Platter by reworking the mold, mainly to remove the names of the planets, but fortuitously increasing

2418-452: Is determined by the projected area of the part being moulded. This projected area is multiplied by a clamp force of from 1.8 to 7.2 tons for each square centimetre of the projected areas. As a rule of thumb, 4 or 5 tons/in can be used for most products. If the plastic material is very stiff, it requires more injection pressure to fill the mould, and thus more clamp tonnage to hold the mould closed. The required force can also be determined by

2511-436: Is facilitated by this breadth of design considerations and possibilities. Injection moulding is used to create many things such as wire spools , packaging , bottle caps , automotive parts and components, toys, pocket combs , some musical instruments (and parts of them), one-piece chairs and small tables, storage containers, mechanical parts (including gears), and most other plastic products available today. Injection moulding

2604-401: Is immersed in paraffin oil (kerosene). A voltage applied between tool and mould causes spark erosion of the mould surface in the inverse shape of the electrode. The number of cavities incorporated into a mould directly correlate in moulding costs. Fewer cavities require far less tooling work, so limiting the number of cavities lowers initial manufacturing costs to build an injection mould. As

2697-443: Is injected into the part. Gate solidification time is important, as this determines cycle time and the quality and consistency of the product, which itself is an important issue in the economics of the production process. Holding pressure is increased until the parts are free of sinks and part weight has been achieved. Injection moulding is a complex technology with possible production problems. They can be caused either by defects in

2790-424: Is known as insert moulding and allows single parts to contain multiple materials. This process is often used to create plastic parts with protruding metal screws so they can be fastened and unfastened repeatedly. This technique can also be used for In-mould labelling and film lids may also be attached to moulded plastic containers. A parting line , sprue , gate marks, and ejector pin marks are usually present on

2883-430: Is maintained to compensate for material shrinkage. In the next step, the screw turns, feeding the next shot to the front screw. This causes the screw to retract as the next shot is prepared. Once the part is sufficiently cool, the mould opens and the part is ejected. Traditionally, the injection portion of the moulding process was done at one constant pressure to fill and pack the cavity. This method, however, allowed for

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2976-428: Is often used. Mild steel, aluminium, nickel or epoxy are suitable only for prototype or very short production runs. Modern hard aluminium (7075 and 2024 alloys) with proper mould design, can easily make moulds capable of 100,000 or more part life with proper mould maintenance. Moulds are built through two main methods: standard machining and EDM . Standard machining, in its conventional form, has historically been

3069-417: Is quite high for thermoplastics relative to many other materials. The packing pressure is applied until the gate (cavity entrance) solidifies. Due to its small size, the gate is normally the first place to solidify through its entire thickness. Once the gate solidifies, no more material can enter the cavity; accordingly, the screw reciprocates and acquires material for the next cycle while the material within

3162-449: Is repeated. For a two-shot mould, two separate materials are incorporated into one part. This type of injection moulding is used to add a soft touch to knobs, to give a product multiple colours, or to produce a part with multiple performance characteristics. For thermosets, typically two different chemical components are injected into the barrel. These components immediately begin irreversible chemical reactions that eventually crosslinks

3255-507: Is the disc golf disc, which is used in the sport of disc golf . Disc golf discs are similar in size and shape to ultimate discs, but have different weights and designs. The material often used to make golf discs is polypropylene . There are three main types of disc golf discs: drivers, mid-range discs, and putters. Each type is designed for a specific purpose, with drivers being used for long-distance throws, mid-range discs for more controlled shots, and putters for short and accurate throws into

3348-417: Is the most common modern method of manufacturing plastic parts; it is ideal for producing high volumes of the same object. Injection moulding uses a ram or screw-type plunger to force molten plastic or rubber material into a mould cavity; this solidifies into a shape that has conformed to the contour of the mould. It is most commonly used to process both thermoplastic and thermosetting polymers , with

3441-613: Is to advance the disc on the field of play by passing, and score points by throwing the flying disc to a teammate in a small scoring area. The game of guts was invented by the Healy Brothers in the 1950s and developed at the International Frisbee Tournament (IFT) in Eagle Harbor, Michigan . Two teams of one to five team members stand in parallel lines facing each other across a court and throw flying discs at members of

3534-423: Is used in areas of the mould that require fast heat removal or areas that see the most shear heat generated. The moulds can be manufactured either by CNC machining or by using electrical discharge machining processes. The mould consists of two primary components, the injection mould (A plate) and the ejector mould (B plate). These components are also referred to as moulder and mouldmaker . Plastic resin enters

3627-402: Is used to fill the mould cavity, compensate for shrinkage, and provide a cushion (approximately 10% of the total shot volume, which remains in the barrel and prevents the screw from bottoming out) to transfer pressure from the screw to the mould cavity. When enough material has gathered, the material is forced at high pressure and velocity into the part forming cavity. The exact amount of shrinkage

3720-482: The target . The rim for golf discs are sharper than ultimate frisbee, to reduce wind drag . Each type of golf disc has hundreds of variations, subject to a uniform requirement in the size of discs: the minimum diameter of a golf disc is 21  cm (8.3  in ). Freestyle discs are another variation of flying discs that are used in freestyle Frisbee competitions. These discs are usually smaller and lighter than other types of flying discs. Most freestyle discs have

3813-482: The 1940s because World War II created a huge demand for inexpensive, mass-produced products. In 1946, American inventor James Watson Hendry built the first screw injection machine, which allowed much more precise control over the speed of injection and the quality of articles produced. This machine also allowed material to be mixed before injection, so that coloured or recycled plastic could be added to virgin material and mixed thoroughly before being injected. In

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3906-495: The 1970s, Hendry went on to develop the first gas-assisted injection moulding process, which permitted the production of complex, hollow articles that cooled quickly. This greatly improved design flexibility as well as the strength and finish of manufactured parts while reducing production time, cost, weight and waste. By 1979, plastic production overtook steel production, and by 1990, aluminium moulds were widely used in injection moulding. Today, screw injection machines account for

3999-600: The Pluto Platter by that term, which was derived from the Connecticut-based pie manufacturer Frisbie Pie Company , a supplier of pies to Yale University , where students had started a campus craze tossing empty pie tins stamped with the company's logo—the way that Morrison and his wife had in 1937. In November 1957, the Frisbee was featured in what may be the first rock musical ever performed, Anything & Everything , written by Ted Nelson. The game of Frisbee (spelled Frisby)

4092-546: The Whirlo-Way, after the famous racehorse . He and business partner Warren Franscioni began producing the first plastic discs by 1948, after design modifications and experimentation with several prototypes. They renamed them the "Flyin-Saucer" in the wake of reported unidentified flying object sightings . "We worked fairs, demonstrating it," Morrison told the Virginian-Pilot . The two of them once overheard someone saying that

4185-486: The World Frisbee Championships (1974), Pasadena, California, are the earliest Frisbee competitions that presented the Frisbee as a new disc sport. Before these tournaments, the Frisbee was considered a toy and used for recreation. Double disc court was invented and introduced in 1974 by Jim Palmeri, a sport played with two flying discs and two teams of two players. Each team defends its court and tries to land

4278-400: The article using pins, sleeves, strippers, etc., may cause undesirable impressions or distortion, so care must be taken when designing the mould. The standard method of cooling is passing a coolant (usually water) through a series of holes drilled through the mould plates and connected by hoses to form a continuous pathway. The coolant absorbs heat from the mould (which has absorbed heat from

4371-419: The chemical precursors are minimised in the injection unit. The residence time can be reduced by minimising the barrel's volume capacity and by maximising the cycle times. These factors have led to the use of a thermally isolated, cold injection unit that injects the reacting chemicals into a thermally isolated hot mould, which increases the rate of chemical reactions and results in shorter time required to achieve

4464-453: The conventional process description above, there are several important moulding variations including, but not limited to: A more comprehensive list of injection moulding processes may be found here: [1] Like all industrial processes, injection molding can produce flawed parts, even in toys. In the field of injection moulding, troubleshooting is often performed by examining defective parts for specific defects and addressing these defects with

4557-410: The core and cavity of moulds further influences cost. Rubber injection moulding process produces a high yield of durable products, making it the most efficient and cost-effective method of moulding. Consistent vulcanisation processes involving precise temperature control significantly reduces all waste material. Usually, the plastic materials are formed in the shape of pellets or granules and sent from

4650-501: The cost of design, fabrication , processing , and quality monitoring. The skillful mould and part designer positions these aesthetic detriments in hidden areas if feasible. In 1846 the British inventor Charles Hancock, a relative of Thomas Hancock , patented an injection molding machine. American inventor John Wesley Hyatt , together with his brother Isaiah, patented one of the first injection moulding machines in 1872. This machine

4743-435: The design of the mould or the characteristics of the process itself. Trials are often performed before full production runs in an effort to predict defects and determine the appropriate specifications to use in the injection process. When filling a new or unfamiliar mould for the first time, where shot size for that mould is unknown, a technician/tool setter may perform a trial run before a full production run. They start with

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4836-424: The direction that the mould opens, unless parts of the mould are designed to move from between such overhangs when the mould opens using components called Lifters. Sides of the part that appear parallel with the direction of draw (the axis of the cored position (hole) or insert is parallel to the up and down movement of the mould as it opens and closes) are typically angled slightly, called draft, to ease release of

4929-546: The disc is an airfoil in cross-section which allows it to fly by reducing the drag and increasing lift as it moves through the air, compared to a flat plate. Spinning the disc imparts a stabilizing gyroscopic force, allowing it to be both aimed with accuracy and thrown for distance. A wide range is available of flying disc variants. Those for disc golf are usually smaller but denser compared to ultimate frisbee, and tailored for particular flight profiles to increase or decrease stability and distance. The longest recorded disc throw

5022-591: The father of Frisbee sports; he founded the International Frisbee Association and appointed Dan Roddick as its head. Roddick began establishing North American Series (NAS) tournament standards for various Frisbee sports, such as Freestyle , Guts , Double Disc Court , and overall events. Headrick later helped to develop the sport of disc golf, which was first played with Frisbees and later with more aerodynamic beveled-rim discs, by inventing standardized targets called "pole holes". When Headrick died, he

5115-406: The final part. None of these features are typically desired, but are unavoidable due to the nature of the process. Gate marks occur at the gate that joins the melt-delivery channels (sprue and runner) to the part forming cavity. Parting line and ejector pin marks result from minute misalignments, wear, gaseous vents, clearances for adjacent parts in relative motion, and/or dimensional differences of

5208-407: The first soluble forms of cellulose acetate in 1903, which was much less flammable than cellulose nitrate . It was eventually made available in a powder form from which it was readily injection moulded. Arthur Eichengrün developed the first injection moulding press in 1919. In 1939, Arthur Eichengrün patented the injection moulding of plasticised cellulose acetate. The industry expanded rapidly in

5301-404: The game is to advance the disc and score points by eventually passing the disc to a team member in the opposing team's end zone. Players may not run while holding the disc. Injection molded Injection moulding (U.S. spelling: injection molding ) is a manufacturing process for producing parts by injecting molten material into a mould, or mold . Injection moulding can be performed with

5394-493: The hot plastic) and keeps the mould at a proper temperature to solidify the plastic at the most efficient rate. To ease maintenance and venting, cavities and cores are divided into pieces, called inserts , and sub-assemblies, also called inserts , blocks , or chase blocks . By substituting interchangeable inserts, one mould may make several variations of the same part. More complex parts are formed using more complex moulds. These may have sections called slides, that move into

5487-404: The injection and clamping cycles; however, aluminium moulds are cost-effective in low-volume applications, as mould fabrication costs and time are considerably reduced. Many steel moulds are designed to process well over a million parts during their lifetime and can cost hundreds of thousands of dollars to fabricate. When thermoplastics are moulded, typically pelletised raw material is fed through

5580-670: The license and distribution rights to the Frisbie Pie Co. He re-launched the company in November 2016 in Bridgeport, Connecticut and began distributing pies throughout the region in early 2017. They sell pies based on the original Frisbie Pie Company recipe. In Back to the Future Part III , Marty McFly ( Michael J. Fox ) while time-travelling to the Wild West, finds amusement in seeing

5673-411: The material into a single connected network of molecules. As the chemical reaction occurs, the two fluid components permanently transform into a viscoelastic solid. Solidification in the injection barrel and screw can be problematic and have financial repercussions; therefore, minimising the thermoset curing within the barrel is vital. This typically means that the residence time and temperature of

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5766-488: The material used and the size of the part. Larger parts require higher clamping force. Mould or die are the common terms used to describe the tool used to produce plastic parts in moulding. Since moulds have been expensive to manufacture, they were usually only used in mass production where thousands of parts were being produced. Typical moulds are constructed from hardened steel , pre-hardened steel, aluminium, and/or beryllium-copper alloy. The choice of material for

5859-548: The melting surfaces contacting the injected polymer. Dimensional differences can be attributed to non-uniform, pressure-induced deformation during injection, machining tolerances , and non-uniform thermal expansion and contraction of mould components, which experience rapid cycling during the injection, packing, cooling, and ejection phases of the process. Mould components are often designed with materials of various coefficients of thermal expansion. These factors cannot be simultaneously accounted for without astronomical increases in

5952-407: The method of building injection moulds. With technological developments, CNC machining became the predominant means of making more complex moulds with more accurate mould details in less time than traditional methods. The electrical discharge machining (EDM) or spark erosion process has become widely used in mould making. As well as allowing the formation of shapes that are difficult to machine,

6045-412: The mold is not only based on cost considerations, but also has a lot to do with the product life cycle . In general, steel moulds cost more to construct, but their longer lifespan offsets the higher initial cost over a higher number of parts made before wearing out. Pre-hardened steel moulds are less wear-resistant and are used for lower volume requirements or larger components; their typical steel hardness

6138-493: The mould causes the slides to move forward along the angle pins. A mould can produce several copies of the same parts in a single "shot". The number of "impressions" in the mould of that part is often incorrectly referred to as cavitation. A tool with one impression is often called a single impression (cavity) mould. A mould with two or more cavities of the same parts is usually called a multiple impression (cavity) mould. (Not to be confused with "Multi- shot moulding" {which

6231-399: The mould cavity through a gate and runner system. The mould remains cold so the plastic solidifies almost as soon as the mould is filled. The sequence of events during the injection mould of a plastic part is called the injection moulding cycle. The cycle begins when the mould closes, followed by the injection of the polymer into the mould cavity. Once the cavity is filled, a holding pressure

6324-404: The mould cools so that it can be ejected and be dimensionally stable. This cooling duration is dramatically reduced by the use of cooling lines circulating water or oil from an external temperature controller. Once the required temperature has been achieved, the mould opens and an array of pins, sleeves, strippers, etc. are driven forward to demould the article. Then, the mould closes and the process

6417-522: The mould through a sprue or gate in the injection mould; the sprue bushing is to seal tightly against the nozzle of the injection barrel of the moulding machine and to allow molten plastic to flow from the barrel into the mould, also known as the cavity. The sprue bushing directs the molten plastic to the cavity images through channels that are machined into the faces of the A and B plates. These channels allow plastic to run along them, so they are referred to as runners. The molten plastic flows through

6510-483: The moulds, or more often by the moulding process itself. Frisbie Pie Company Frisbie supplied pies to many Connecticut retailers and restaurants, including the Middlebury College campus in nearby Vermont. Middlebury students discovered that the pie tins, inverted, had an airfoil shape, which enabled them to be thrown, with practice, in various trajectories . In 1957, the Wham-O toy company, had

6603-427: The number of cavities play a vital role in moulding costs, so does the complexity of the part's design. Complexity can be incorporated into many factors such as surface finishing, tolerance requirements, internal or external threads, fine detailing or the number of undercuts that may be incorporated. Further details, such as undercuts, or any feature that needs additional tooling, increases mould cost. Surface finish of

6696-543: The opposing team. A patented game scoring points by throwing and deflecting the flying disc and hitting or entering the goal. The game ends when a team scores exactly 21 points or "chogs" the disc for an instant win. The most widely played disc game began in the late 1960s with Joel Silver and Jared Kass. In the 1970s, it developed as an organized sport with the creation of the Ultimate Players Association by Dan Roddick, Tom Kennedy and Irv Kalb. The object of

6789-548: The pair were using wires to make the discs hover, so they developed a sales pitch: "The Flyin' Saucer is free, but the invisible wire is $ 1.00." (equivalent to $ 13 in 2023) "That's where we learned we could sell these things," he said, because people were enthusiastic about them. Morrison and Franscioni ended their partnership in early 1950, and Morrison formed his own company in 1954 called American Trends to buy and sell "Flyin Saucers" (no hyphen after 1953), which were being made of

6882-426: The part from the mould. Insufficient draft can cause deformation or damage. The draft required for mould release is primarily dependent on the depth of the cavity; the deeper the cavity, the more draft necessary. Shrinkage must also be taken into account when determining the draft required. If the skin is too thin, then the moulded part tends to shrink onto the cores that form while cooling and cling to those cores, or

6975-408: The part may warp, twist, blister or crack when the cavity is pulled away. A mould is usually designed so that the moulded part reliably remains on the ejector (B) side of the mould when it opens, and draws the runner and the sprue out of the (A) side along with the parts. The part then falls freely when ejected from the (B) side. Tunnel gates, also known as submarine or mould gates, are located below

7068-415: The parting line or mould surface. An opening is machined into the surface of the mould on the parting line. The moulded part is cut (by the mould) from the runner system on ejection from the mould. Ejector pins, also known as knockout pins, are circular pins placed in either half of the mould (usually the ejector half), which push the finished moulded product, or runner system out of a mould. The ejection of

7161-486: The pressure should be sufficient to allow for the desired speed, pressure limitations during this stage are undesirable. Once the cavity is 98% full, the machine switches from velocity control to pressure control , where the cavity is "packed out" at a constant pressure, where sufficient velocity to reach desired pressures is required. This lets workers control part dimensions to within thousandths of an inch or better. Although most injection moulding processes are covered by

7254-420: The process allows pre-hardened moulds to be shaped so that no heat treatment is required. Changes to a hardened mould by conventional drilling and milling normally require annealing to soften the mould, followed by heat treatment to harden it again. EDM is a simple process in which a shaped electrode, usually made of copper or graphite, is very slowly lowered onto the mould surface over a period of many hours, which

7347-412: The raw material forward, mixes and homogenises the thermal and viscous distributions of the polymer, and reduces the required heating time by mechanically shearing the material and adding a significant amount of frictional heating to the polymer. The material feeds forward through a check valve and collects at the front of the screw into a volume known as a shot . A shot is the volume of material that

7440-409: The raw material manufacturers in paper bags. With injection moulding, pre-dried granular plastic is fed by a forced ram from a hopper into a heated barrel. As the granules are slowly moved forward by a screw-type plunger, the plastic is forced into a heated chamber, where it is melted. As the plunger advances, the melted plastic is forced through a nozzle that rests against the mould, allowing it to enter

7533-477: The rights to a plastic flying disc design, called the "Pluto Platter". To capitalize on the craze over the pie tins, known colloquially as "Frisbies", they took the same name for their toy, changing the spelling to " Frisbee " to avoid trademark infringement. The Bridgeport pie factory closed in 1958; Frisbie brand pies were bought out by Table Talk Pies . In 2016, Dan O’Connor, a Fairfield, Connecticut resident, Frisbee player, collector and historian, acquired

7626-416: The rim thickness and mass in the process, creating a more controllable disc that could be thrown more accurately. Wham-O changed their marketing strategy to promote Frisbee use as a new sport, and sales increased. In 1964, the first professional model went on sale. Headrick patented its design; it featured raised ridges (the "Rings of Headrick") that were claimed to stabilize flight. Headrick became known as

7719-409: The runner and enters one or more specialised gates and into the cavity geometry to form the desired part. The amount of resin required to fill the sprue, runner and cavities of a mould comprises a "shot". Trapped air in the mould can escape through air vents that are ground into the parting line of the mould, or around ejector pins and slides that are slightly smaller than the holes retaining them. If

7812-441: The same parts or can be unique and form multiple different geometries during a single cycle. Moulds are generally made from tool steels , but stainless steels and aluminium moulds are suitable for certain applications. Aluminium moulds are typically ill-suited for high volume production or parts with narrow dimensional tolerances, as they have inferior mechanical properties and are more prone to wear, damage, and deformation during

7905-411: The sport of Ultimate . Ultimate discs are made of durable plastic (often polyethylene ) and are designed to be thrown for maximum distance and accuracy. Ultimate has a unique standard with a diameter of 10.75 inches (27.3  cm ) and a weight of 175 grams (6.2  oz ). For competitive uses, WFDF or other official organizations set disc standards to ensure quality. Another type of flying disc

7998-803: The strength and function required for the final part, as well as the cost, but also each material has different parameters for moulding that must be taken into account. Other considerations when choosing an injection moulding material include flexural modulus of elasticity, or the degree to which a material can be bent without damage, as well as heat deflection and water absorption. Common polymers like epoxy and phenolic are examples of thermosetting plastics while nylon , polyethylene , and polystyrene are thermoplastic. Until comparatively recently, plastic springs were not possible, but advances in polymer properties make them now quite practical. Applications include buckles for anchoring and disconnecting outdoor-equipment webbing. Injection moulding machines consist of

8091-493: The time: "That got the wheels turning, because you could buy a cake pan for five cents, and if people on the beach were willing to pay a quarter for it, well—there was a business." The Morrisons continued their business until World War II , when Walter served in the Army Air Force flying P-47s , and then was a prisoner of war. After the war, Morrison sketched a design for an aerodynamically improved flying disc that he called

8184-410: The total number of available materials for injection moulding has increased at a rate of 750 per year; there were approximately 18,000 materials available when that trend began. Available materials include alloys or blends of previously developed materials, so product designers can choose the material with the best set of properties from a vast selection. Major criteria for selection of a material are

8277-415: The trapped air is not allowed to escape, it is compressed by the pressure of the incoming material and squeezed into the corners of the cavity, where it prevents filling and can also cause other defects. The air can even become so compressed that it ignites and burns the surrounding plastic material. To allow for removal of the moulded part from the mould, the mould features must not overhang one another in

8370-458: The vast majority of all injection machines. The plastic injection moulding industry has evolved over the years from producing combs and buttons to producing a vast array of products for many industries including automotive, medical, aerospace, consumer products, toys, plumbing , packaging, and construction. Most polymers, sometimes referred to as resins, may be used, including all thermoplastics, some thermosets, and some elastomers. Since 1995,

8463-420: The volume used of the former being considerably higher. Thermoplastics are prevalent due to characteristics that make them highly suitable for injection moulding, such as ease of recycling, versatility for a wide variety of applications, and ability to soften and flow on heating. Thermoplastics also have an element of safety over thermosets; if a thermosetting polymer is not ejected from the injection barrel in

8556-751: Was cremated, and his ashes were molded into memorial discs and given to family and close friends and sold to benefit The Ed Headrick Memorial Museum. In 1998, the Frisbee was inducted into the National Toy Hall of Fame . In addition, many championships have sprung up around the world and the sport has become very popular, with nine-time champion Miguel Larrañaga from Spain being the leading exponent of frisbee throwing. Flying discs , or known as Frisbee, have variations produced for different purposes to optimize variations between branches of disc sports. The three main categories are: ultimate disc, golf disc, and freestyle disc. Ultimate discs are designed to be used in

8649-466: Was relatively simple compared to machines in use today: it worked like a large hypodermic needle , using a plunger to inject plastic through a heated cylinder into a mould. The industry progressed slowly over the years, producing products such as collar stays , buttons, and hair combs(generally though, plastics, in its modern definition, are a more recent development c.  1950s ). The German chemists Arthur Eichengrün and Theodore Becker invented

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