Third angle projection of a bracket


Figure 2.12 shows a third angle projection drawing of a small bracket. In this case, the plan view and the inverted plan view are projected from the front face. Note that the arrangements of the views are still in third angle projection but they are arranged differently from the views in Figure 2.11. Another example of third angle projection is seen in the truncated cone within the title box in Figure 2.12. Here, the cone is on its side and only two views are shown yet they are still in third angle projection. The reason the cone is shown within the box is that it is the standard symbol for third angle projection recommended in ISO 128" 1982. The standard recommends that this symbol be used within the title block of an engineering drawing rather than the words 'third angle projection' because ISO uses symbology to get away from a dependency on any particular language. Third angle projection has been used to describe engineering artefacts from the earliest of times. In the National Railway Museum in York, there is a drawing of George Stephenson's 'Rocket' steam locomotive, dated 1840. The original is in colour. This is a cross between an engineering drawing (as described above) and an artistic sketch. Shadows can be seen in both orthographic views. Presumably this was done to make the drawings as realistic as possible. This is an elegant drawing and nicely illustrates the need for 'engineered' drawings for the manufacture of the Rocket locomotive. Bailey and Glithero (2000) state, 'The Rocket is also important in representing one of the earliest achievements of mechanical engineering design'. In this context, the use of third angle projection is significant, bearing in mind that the Rocket was designed and manufactured during the transition period between the millwrightbased manufacturing practice of the craft era and the factory-based manufacturing practice of the industrial revolution. However, third angle projection was used much earlier than this. It was used by no less than James Watt in 1782 for drawing John Wilkinson's Old Forge engine in Bradley (Boulton and Watt Collection at Birmingham Reference Library). In 1781 Watt did all his own drawing but from 1790 onwards, he established a drawing office and he had one assistant, Mr John Southern. These drawings from the beginning of the industrial revolution are significant. They illustrate that two of the fathers of the industrial revolution chose to use third angle projection. It would seem that at the beginning of the 18th century third angle was preferred, yet a century later first angle projection (explained below) had become the preferred method in the UK. Indeed, the 1927 BSI drawing standard states that third angle projection is the preferred UK method and third angle projection is the preferred USA method. It is not clear why the UK changed from one to the other. However, what is clear is that it has changed back again because the favoured projection method in the UK is now third angle. 

Engineering Drawing for Manufacture
by Brian Griffiths
Publisher: Elsevier Science & Technology Books

Injection Blow Moulding

This process is a modification of the process and injection molding extrusi. In Extrusion blow molding, a tube is produced from the extruder and then clamped into the mold (mold) with a cavity larger than the tube diameter. Then the wind blows to fill the cavity. The process usually by blowing a blast of water with a pressure of 50-100 psi. In continuous operation extrusi process with a closed mold around the tube, both the top and bottom closed. Then after spending the cold products made ​​product by ejection. Pipes and tubes made ​​with a continuous blow molding, where the pipe or tube stretched and blown inside the mold. In the Injection Blow Molding, A short tube (parison) is generated. Dies are then opened and the parison is transferred into a blow molding die. Hot air is injected into the parison, with the spread and fill the cavity. The types of products are bottles and containers. In a multilayer blow molding is used coextruder tube or parison-parison to form a multi-layer structure. Examples of this type of structure is a multi-layer plastic food and beverage packaging. (bid / multiple sources)

Third angle projection

Figure 2.10 shows a small cornflake packet (courtesy of Kellogg's) that has been cut and folded back to produce a development of a set of six connected faces. Each one of these faces represents a true view of the original box. Each face (view) is folded out from an adjacent face (view). Folding the faces back and gluing could reassemble the packet. The development in Figure 2.10 is but one of a number of possible developments. For example, the top and bottom small faces could have been connected to (projected from) the back face (the 'bowl game' face) rather than as shown. Alternatively, the top and bottom faces could have been connected. Figure 2.11 (courtesy of Kellogg's) shows the same layout but with the views separated from each other such that it is no longer a development but a series of individual views of the faces. The various views have been labelled. The major face of the packet is the one with the title 'Corn Flakes'. This face is the important one because it is the one that would be placed facing outwards on a supermarket shelf. This view is termed the 'front view' and all the other views are projected from it. Note the obvious names of the other views. All the other five views are projected from the front face view as per the layout in Figure 2.10. This arrangement of views is called third angle orthographic projection. The reason why this is so is explained below. The third angle orthographic projection 'law' is that the view one sees from your viewing position is placed on the same side as you view it from. For example, the plan view is seen from above so it is placed above the front face because it is viewed from that direction. The right-side view is placed on the right-hand side of the front view. Similarly, the left-side view is placed to the left of the front view. In this case, the rear view is placed on the left of the left-side view but it could have also been placed to the right of the right-side view. Note that opposite views (of the packet) can only be projected from the same face because orthographic relationships must be maintained. For example, in Figure 2.11, the plan view and inverted plan view are both projected from the front view. They could just as easily have both been projected from the right-side view (say) but not one from the front face and one from the rightside view. It is doesn't matter which arrangement of views is used as long as the principle is followed that you place what you see at the position from which you are looking. 
Engineering Drawing for Manufacture
by Brian Griffiths
Publisher: Elsevier Science & Technology Books
 

Orthographic projection

In orthographic projection, the front face is always parallel to the picture frame and the projectors are perpendicular to the picture frame (see Figure 2.9). This means that one only ever sees the true front face that is a 2D view of the object. The receding faces are therefore not seen. This is the same as on an oblique projection but with the projectors perpendicular rather than at an angle. The other faces can also be viewed if the object is rotated through 90 degree .There will be six such orthographic views. These are stand-alone views but if the object is to be 'reassembled' from these six views there must be a law that defines how they are related. In engineering drawing there are two laws, these are first or third angle projection. In both cases, the views are the same; the only thing that differs is the position of the views with respect to each other. The most common type of projection is third angle projection.
Engineering Drawing for Manufacture by Brian Griffiths Publisher:
Elsevier Science &
Technology Books

Oblique projection

In oblique projection, the object is aligned such that one face (the front face) is parallel to the picture plane. The projection lines are still parallel but they are not perpendicular to the picture plane. This produces a view of the object that is 3D. The front face is a true view (see Figure 2.7). It has the advantage that features of the front face can be drawn exactly as they are, with no distortion. The receding faces can be drawn at any angle that is convenient for illustrating the shape of the object and its features. The front face will be a true view, and it is best to make this one the most complicated of the faces. This makes life easier! Most oblique projections are drawn at an angle of 45 ~ and at this angle the foreshortening is 50%. This is called a Cabinet projection. This is because of its use in the furniture industry. If the 45 ~ angle is used and there is no foreshortening it is called a Cavalier projection. The problem with Cavalier projection is that, because there is no foreshortening, it looks peculiar and distorted. Thus, Cabinet projection is the preferred method for constructing an oblique projection. An oblique drawing of the bearing bracket in Cabinet projection is shown in Figure 2.8. For convenience, the front view with circles was chosen as the true front view. This means that the circles are true circles and therefore easy to draw. The method of construction for oblique projection is similar to the method described above for isometric projection except that the angles are not 30 ~ but 45 ~ . Enclosing rectangles are again used and transposed onto the 45 ~ oblique planes using 50% foreshortening. Engineering Drawing for Manufacture by Brian Griffiths Publisher: Elsevier Science & Technology Books

Structural foam molding

Structural foam molding is a modified version injection where conventional molding plastic products consist of a dense outer surface of the skin that surrounds the inside (foam). This process is suitable for large-scale production, the product is relatively thick. Foam cores are produced from this process is suitable for bending applications. If the skin has the highest tensile strength and compressive stress, then the neutral axis of the work on the weaker parts of the inner foam. This process offers several advantages from the manufacturing process because it is able to produce products that are complex and have a low voltage so that the tendency for reduced bending or distorted. Then the clamping force is required of this process is lower than conventional injection molding process. This process is widely used for the production of large-sized plastic such as engine housings, chassis, computer housings, bin-bin storage, pallets and others. Polymers are often used for this process is the HOPE, PP, ABS and PC. Resins used in the Low Pressure is applied to this process consists of a small amount of blowing or foaming agent, this type of Chemical Blowing Agent (CBA) decomposition temperatures approaching the temperature of the resin. During the CBA process is decomposed in a large volume of gas as the beginning of a foaming process. Then injected into the cavity short shot. The skin is formed when the gas pressure near the surface of the collapse due to the mold surface. Furthermore, the gas spreads pressing short shot to complete filling cavity. After filling the gas continued to press with the uniform in all directions, pressing the dense skin on the mold surface, effectively also eliminate sink marks. Compared with the conventional injection process, voltage and much reduced shrinkage due to pressure on the cavity is relatively uniform. Before the ejection process must be ensured that the product starts cold and dense. Besides the advantages mentioned above there are a number of disadvantages when compared with conventional injection molding process, namely because the thickness of the walls are made then the cycle time achieved the longer, the consumption of the material also becomes more and more. For this type of process better position the gate at the thinnest part, is to facilitate filling the cavity thick sections. Unlike in conventional injection molding process on the premature solidification of a thin section of a thicker section and the gate does not occur. (Bid / multiple sources)

Isometric projection

In isometric projection, the projection plane forms three equal angles with the co-ordinate axis. Thus, considering the isometric cube in Figure 2.4, the three cube axes are foreshortened to the same amount, i.e. AB = AC = AD. Two things result from this, firstly, the angles a = b = 30 ~ and secondly, the rear (hidden) corner of the cube is coincident with the upper corner (corner D). Thus, if the hidden edges of the cube had been shown, there would be dotted lines going from D to F, D to C and D to B. The foreshortening in the three axes is such that AB = AC = AD = (2/3) o.5 = 0.816. Since isometric projections are pictorial projections and dimensions are not normally taken from them, size is not really important. Hence, it is easier to ignore the foreshortening and just draw the object full size. This makes the drawing less complicated but it does have the effect of apparently enlarging the object by a factor 1.22 (1 + 0.816). Bearing this in mind and the fact that both angles are 30 ~ it is not surprising that isometric projection is the most commonly used of the three types of axonometric projection. The method of constructing isometric projections is shown in the diagrams in Figures 2.5 and 2.6. An object is translated into isometric projection by employing enclosing shapes (typically squares and rectangles) around important features and along the three axes. Considering the isometric cube in Figure 2.4, the three sides are three squares that are 'distorted' into parallelograms, aligned with the three isometric axes. Internal features can be projected from these three parallelograms. The method of constructing an isometric projection of a flanged bearing block is shown in Figure 2.5. The left-hand drawing shows the construction details and the right-hand side shows the 'cleaned up' final isometric projection. An enclosing rectangular cube could be placed around the whole bearing block but this enclosing rectangular cube is not shown on the construction details diagram because of the complexity. Rather, the back face rectangle CDEF and the bottom face ABCF are shown. Based on these two rectangles, the construction method is as follows. Two shapes are drawn on the isometric back plane CDEE These are the base plate rectangle CPQF and the isometric circles within the enclosing square LMNO. Two circles are placed within this enclosing square. They represent the outer and inner diameters of the bearing at the back face. The method of constructing an isometric circle is shown in the example in Figure 2.6. Here a circle of diameter ab is enclosed by the square abcd. This isometric square is then translated onto each face of the isometric cube. The square abcd thus becomes a parallelogram abcd. The method of constructing the isometric circles within these squares is as follows. The isometric square is broken down further into a series of convenient shapes, in this case five small long-thin rectangles in each quadrant. These small rectangles are then translated on to the isometric cube. The intersection heights ef, gh, ij and kl are then projected onto the equivalent rectangles on the isometric projection. The dots corresponding to the points fhjl are the points on the isometric circles. These points can be then joined to produce isometric circles. The isometric circles can either be produced freehand or by using matching ellipses. Returning to the isometric bearing plate in Figure 2.5, the isometric circles representing the bearing outside and inside diameters are constructed within the isometric square LMNO. Two angled lines PR are drawn connecting the isometric circles to the base CPQE The rear shape of the bearing bracket is now complete within the enclosing rectangle CDEE Returning to the isometric projection drawing of the flanged bearing block in Figure 2.5. The inside and outside bearing diameters in the isometric form are now projected forward and parallel to the axis BC such that two new sets of isometric circles are constructed as shown. The isometric rectangle CPQF is then projected forward, parallel to BC that produces rectangle ABST, thus completing the bottom plate of the bracket. Finally, the web front face UVWX is constructed. This completes the various constructions of the isometric bearing bracket and the final isometric drawing on the right-hand side can be constructed and hidden detail removed. Any object can be constructed as an isometric drawing provided the above rules of enclosing rectangles and squares are followed which are then projected onto the three isometric planes. 
Engineering Drawing for Manufacture by Brian Griffiths 
Publisher: Elsevier Science & 
Technology Books

The raw material for plastic products

The raw material for plastic products, petroleum, natural gas and coal as a carbon source. The starting material is now part of the pyrolysis recycling plants are used: The name of the plastic is a generic term for synthetic or natural product produced by the conversion of macromolecular materials. These macromolecules consist of individual, chemically linked to each other building blocks of molecules, called monomers. With a series of monomers are called polymers. In this case, a single polymer chain is formed of thousands of monomers. Plastics can be composed of linear molecules, branched or cross-linked. Linear and branched macromolecules that no network should be moved by using heat. The molecules can slide to one another, that is material to flow and form. Therefore, the polymer material known as thermoplastic. The longer the molecular chain of plastic material, the higher is its strength properties. Thermoplastic properties ranging from soft to hard, difficult or hard and brittle. For elastomers, the macromolecule is a weak network. They are at room temperature before the chain due to their high mobility in the rubber state. Elastomers are not meltable and insoluble. Plastic with a strong spatial cross-linked chains of molecules known as thermosets. They act hard and brittle at room temperature. They are insoluble and infusible, and elastomers. There's also called a thermoplastic elastomer (TPE), the rubber-like material that can melt, however. They are made of thermoplastic materials such as thread-like molecule. In the thermoplastic elastomer, a molecule such as a thread but has segments of individual molecules, which have a strong attraction for one another that they act like a network. There is one main difference between thermoplastics and thermosets and elastomers associated with the process. Thermoplastic melts, processed, and then cooled. Thermosets and elastomers are processed cold and then heated, resulting in (heal) crosslinking of plastic. When Duromerverarbeitung should always be reworked, because the parts can not be formed without form. In the case of thermoplastics, the difference is still between the thermoplastic amorphous and semi-crystalline. This refers to how the thread-like molecules that are stored after cooling. If they are present in the network is completely random, they are called amorphous thermoplastics. The properties of amorphous thermoplastics • can form regular structures because they do not close the packaging. • If you are in a condition such as wipes or cotton balls • in the state of transparent colorless • lower shrinkage than semi-crystalline thermoplastics. translate fr: KraussMaffei Kunstsofftechnick

Types of drawings

There are a number of different types of engineering drawings, each of which meets a particular purpose. There are typically nine types of drawing in common use, these are: 1. A design layout drawing (or design scheme) which represents in broad principles feasible solutions which meet the design requirements. 2. A detail drawing (or single part drawing) shows details of a single artefact and includes all the necessary information required for its manufacture, e.g. the form, dimensions, tolerances, material, finishes and treatments. 3. A tabular drawing shows an artefact or assembly typical of a series of similar things having a common family form but variable characteristics all of which can be presented in tabular form, e.g. a family of bolts. 4. An assembly drawing shows how the individual parts or subassemblies of an artefact are combined together to make the assembly. An item list should be included or referred to. An assembly drawing should not provide any manufacturing details but merely give details of how the individual parts are to be assembled together. 5. A combined drawing is a combination of detail drawings, assembly drawings and an item list. It represents the constituent details of the artefact parts, how they are manufactured, etc., as well as an assembly drawing and an accompanying item list. 6. An arrangement drawing can be with respect to a finished product or equipment. It shows the arrangement of assemblies and parts. It will include important functional as well as performance requirements features. An installation drawing is a particular variation of an arrangement drawing which provides the necessary details to affect installation of typically chemical equipment. 7. A diagram is a drawing depicting the function of a system, typically electrical, electronic, hydraulic or pneumatic that uses symbology. 8. An item list, sometimes called a parts list, is a list of the component parts required for an assembly. An item list will either be included on an assembly drawing or a separate drawing which the assembly drawing refers to. 9. A drawing list is used when a variety of parts make up an assembly and each separate part or artefact is detailed on a separate drawing. All the drawings and item lists will be crossreference on a drawing list. Figures 1.11 and 1.12 show an assembly drawing and a detailed drawing of a small hand vice. The assembly drawing is in orthographic third-angle projection. It shows the layout of the individual parts constituting the assembly. There are actually 14 individual parts in the assembly but several of these are common, such as the four insert screws and two-off hardened inserts such that the number of identifiable separate components numbers 10. On the drawing each of the 10 parts is numbered by a balloon reference system. The accompanying item list shows the part number, the number required and its description. Separate detailed drawings would have to be provided for non-standard parts. One such detailed drawing is shown in Figure 1.12, which is the detailed drawing of the movable jaw. This is shown in third-angle orthographic projection with all the dimensions sufficient for it to be manufactured. Tolerances have been left off for convenience. Engineering Drawing for Manufacture by Brian Griffiths Publisher: Elsevier Science & Technology Books

Product Development Organizations

In addition to crafting an effective development process, successful firms must organize their product development staffs effectively. In this section, we describe several types of organizations used for product development and offer guidelines for choosing among these options. Organizations Are Formed by Establishing Links among Individuals A product development organization is the scheme by which individual designers and developers are linked together into groups. The links among individuals may be formal or informal and include, among others, these types: • Reporting relationships: Reporting relationships give rise to the classic notion of supervisor and subordinate. These are the formal links most frequently shown on an organization chart. • Financial arrangements: Individuals are linked by being part of the same financial entity, such as that defined by a particular budget category or profit-and-loss statement. • Physical layout: Links are created between individuals when they share the same office, floor, building, or site. These links are often informal, arising from spontaneous encounters while at work. Any particular individual may be linked in several different ways to other individuals. For example, an engineer may be linked by a reporting relationship to another engineer in a different building, while being linked by physical layout to a marketing person sitting in the next office. The strongest organizational links are typically those involving performance evaluation, budgets, and other resource allocations.
References and Bibliography
Many current resources are available on the Internet via www.ulrich-eppinger.net Stage-gate product development processes have been dominant in manufacturing firms for the past 30 years. Cooper describes the modem stage-gate process and many of its enabling practices. Cooper, Robert G., Winning at New Products: Accelerating the Process from Idea to Launch, third edition, Perseus Books, Cambridge, MA, 2001.
 

Plastic Manufacturing Process

The establishment of the injection process This process is the process by which plastic pellets melt with the heat and drain liquid into a closed mold. Then the material is cooled and solidified to form the product in accordance with their prints. Then the plastic that has formed is removed from cavitynya the ejection process. Detailed process sequence is as follows: a. Charging Granules of plastic material which is collected in the hopper by gravity will fall and fall into the injection cylinder. Within this cylindrical plastic granules are heated either by heating or heater because the process of a rotating screw. With terisinya nozzle by the spindle screw plastic material will be pushed backward, turning to a position that we have set in accordance with the volume of product to be in print. b. Mould Closing This step closes the plastic molds with moving plate moves toward the fixed plate. Pressure that occurs between the parts of the plastic mold is the maximum pressure plate moves to close the mold until the lock position. The process is called Clamping Force. The capacity of an injection machine is identified with a maximum pressure capability (Clamping Force). c. Forward Barrel [3] Is a step toward moving cylinder injection mold plastic to touch the mouth of the nozzle sprue with a certain pressure. This movement takes place after step and a general, hydraulic clamping. d. Cavity filling The next step is filling cavity. Ready formed plastic fluid driven by a screw (special threaded shaft) into the mold. In this stage the plastic has several phases, namely the filling, packing, and holding. e. Cooling After the mold cavities filled next step is to cool the liquid to solid plastic. This process is followed by a return they will screw into position. f. Mould open The next step is to open the mold. g. Ejection This step is the movement of drivers who are generally located in the middle of the plate to move and push the plastic mold ejector system. This is the last step of the cycle of the injection process. (Bid / multiple sources)

The AMF Development Process

AMF Bowling is a market-pull enterprise. AMF generally drives its development process with a market need and seeks out whatever technology is required to meet that need. Its competitive advantage arises from strong marketing channels, strong brand recognition, and a large installed base of equipment, not from any single proprietary technology. For this reason, the technology-push approach would not be appropriate. AMF products are assembled from components fabricated with relatively conventional processes such as molding, casting, and machining. So the AMF product is clearly not process intensive in the way a food product or a chemical is. Bowling equipment is rarely customized for a particular customer; most of the product development at AMF is aimed at new models of products, rather than at the customization of existing models. For this reason, the customization approach is also inappropriate. AMF chose to establish a development process similar to the generic process. The process proposed by the AMF engineering manager is illustrated in Exhibit 2-6. The representation of the development process used by AMF is a hybrid of those used in Exhibits 2-2 and 2-5, in that it shows the individual activities in the development process as well as the roles of the different development functions in those activities. Note that AMF defines the key functions in product development as marketing, engineering!design, manufacturing, quality assurance, purchasing, and customer service. Also note that there are three major milestones in the process: the project approval, the beginning of tooling fabrication, and the production release. Each of these milestones follows a major review. Although AMF established a standard process, its managers realized that this process would not necessarily be suitable in its entirety for all AMF products. For example, a few of AMF's new products are based on technology platforms. When platform products are developed, the team assumes the use of an existing technology platform during concept development. Nevertheless, the standard development process is the baseline from which a particular project plan begins.
References and Bibliography
Many current resources are available on the Internet via www.ulrich-eppinger.net Stage-gate product development processes have been dominant in manufacturing firms for the past 30 years. Cooper describes the modem stage-gate process and many of its enabling practices. Cooper, Robert G., Winning at New Products: Accelerating the Process from Idea to Launch, third edition, Perseus Books, Cambridge, MA, 2001.

additives

To improve one of the properties of a polymer, usually a polymer will be mixed with a material called additives. The function of these additives is to modify or improve certain properties in accordance with the wishes of the users, such as strength, color, water resistance, heat resistance, electrical resistance and others. Fillers are one of the additive to improve strength, hardness, abrasion resistance, dimensional stability. Plastisizers is additive to menambahn flexibility and lowers the level of soft polymers with glass transition temperaturenya. Molukuler Weight Additive has a low-power high interference. Secondary bond strength is reduced so as to make soft and flexible polymer. Commonly used in PVC, thin sheets, films, cylinders. Most polymers are affected by ultraviolet light (sunlight) and oxygen where it will weaken the influence of the main bonding polymers. Additive used is Carbon Black (soot). These additives absorb a high percentage of ultraviolet radiation. The trick is to add antioxidant polymers. The amount of color variation is needed in the plastic additives required Colorant (dye). This material is organic (Dyes) and inorganic (pigments). Selection of colorant depends on temperature and light in which the pigments dispersed in the polymer. Another additive is heat resistant to the flame retardants. These additives reduce the Flammability of these polymers. When the high temperature most polymers start to burn, burning Traffic depends on the composition of each polymer. Examples of these additives is Compound Chlorine, bromine and Phosphorus. Lubricants can be added to polymers to reduce friction during the manufacturing process. Other uses is to avoid the product sticking to the mold. Can also be a deterrent to the mutual attachment of polymers such as polymer-polymer thin film layer. (bid / multiple sources)

Product Development Process Flows

The product development process generally follows a structured flow of activity and information flow. This allows us to draw process flow diagrams illustrating the process, as shown in Exhibit 2-5. The generic process flow diagram depicts the process used to develop market-pull, technology-push, platform, process-intensive, customized, and high-risk products. Each product development phase (or stage) is followed by a review (or gate) to confirm that the phase is completed and to determine whether the project proceeds. Quick-build products enable a spiral product development process whereby detail design, prototyping, and test activities are repeated a number of times. The process flow diagram for development of complex systems shows the decomposition into parallel stages of work on the many subsystems and components. Once the product development process has been established within an organization, a process flow diagram is used to explain the process to everyone on the team. References and Bibliography Many current resources are available on the Internet via www.ulrich-eppinger.net Stage-gate product development processes have been dominant in manufacturing firms for the past 30 years. Cooper describes the modem stage-gate process and many of its enabling practices. Cooper, Robert G., Winning at New Products: Accelerating the Process from Idea to Launch, third edition, Perseus Books, Cambridge, MA, 2001.

Thermosetting

When the long chain molecules in the polymer related to the opposite (cross-linked) in rule 3 dimensions, the structure becomes one big mclekul with strong covalent bonds. Because during the polymerization and the formation of a network equipped with a permanent structure and could not return to its origin (irreversible), it is called Thermosetting. Thermosetting polymer has a glass transition temperature is not specific. Thermosett polymerization process is generally divided into two phases. The first stage is to separate polymer molecules into linear chains. The second stage is the cross-linking occurs with heat and pressure in the molding process. Due to the nature of the bond, the strength and hardness of thermosett not like thermoplastic, which is not affected by temperature and deformation. One type is termosett Phenolic, which is the result of reactions between Phenol and formaldehyde. A common characteristic of thermosets is a better mechanical properties, heat resistance, chemical resistance, electrical resistance and better dimensional stability. But if the temperature rises high, thermosetting polymers will burn, and burn. Some examples of polymers termosett are as follows: a. Alkyds Is a mixture of alcohol and acid, has the advantage of an excellent electrical insulator, resistant crushed and dimensional stability and low water absorption. b. Aminos Is the urea and melamine has the advantage depends on its composition. Generally amino hard and dense, resistant to abrasion and scratch resistance. Used commonly in furniture, toilet seat, handle and box-box meals. c. Epoxy Mechanical and electrical properties have excellent dimensional stability, a strong adhesive and heat and chemical resistant. Its application is for electronic components that require mechanical strength and good insulation .. d. Phenolics Although fragile and brittle Another advantage is the dimension of a stable, high resistance to heat, water, electrical and chemical. Usually used for handles, panels, telephone, glue material to stone grinding, electronic components, connectors. e. Polyester Have good mechanical properties, heat resistance and chemical resistance. Usually used for a boat, chairs, automotive body. f. Polyamides Good mechanical properties, scratch resistance, low friction, excellent electrical properties. Usually used for seals, valves, piston rings, part-part aerospace, high voltage connectors and safety equipment. g. Silicones Properties are generally good electrical properties, heat resistance and chemical materials. Commonly used for gaskets, seals, waterproof materials. (Bid / multiple sources)

Complex Systems

Larger-scale products such as automobiles and airplanes are complex systems comprised of many interacting subsystems and components. When developing complex systems, modifications to the generic product development process address a number of system-level issues. The concept development phase considers the architecture of the entire system, and multiple architectures may be considered as competing concepts for the overall system. The system-level design phase becomes critical. During this phase, the system is decomposed into subsystems and these further into many components. Teams are assigned to develop each component. Additional teams are assigned the special challenge of integrating components into the subsystems and these into the overall system. Detail design of the components is a highly parallel process in which the many development teams work at once, usually separately. Managing the network of interactions across the components and subsystems is the task of system engineering specialists of many kinds. The testing and refinement phase includes not only system integration, but also extensive testing and validation at all levels. References and Bibliography Many current resources are available on the Internet via www.ulrich-eppinger.net Stage-gate product development processes have been dominant in manufacturing firms for the past 30 years. Cooper describes the modem stage-gate process and many of its enabling practices. Cooper, Robert G., Winning at New Products: Accelerating the Process from Idea to Launch, third edition, Perseus Books, Cambridge, MA, 2001.

Examples of thermoplastics and their characteristics

Examples several types of thermoplastic with the characteristics.
- Poly Vinyl Chlorid (PVC)
Material properties:
a. Hard PVC
Thermoplastic, hard, rigid, transparent, capable of welding and glueing. Resistant to oil, acids, language, alcohol, but less resistant to solvents such as acetone, benzol, esters, temperature resistant up to 80 ° C.
b. Soft PVC
Greatly influenced by the amount of material given the softness softener that occur from such skin becomes rubbery. Clay, crack resistant, capable of being used to a temperature of 80 ° C, while the resistance to chemical solution under the hard PVC.
- Poly Styrol (PS)
Thermoplastics, such as glass, easy to be colored, at room temperature is relatively hard and rigid. Odorless and flammable, resistant to water, acids, bases, alcohols, oils but soluble in benzol, gasoline, acetone, ether. Can be glued and welded.
- Poly Methyl Metha Crylat (PMMA)
Thermoplastic, hard, brittle, scratch resistant, looks like glass, translucent, wear resistant, lightweight, easy to be colored, odorless, resistant to mild acids, alkalis, gasoline and oil, but not resistant to solvents.
- Poly Ethilen (PE)
Thermoplastic, soft material, clay, capable of working up to -40 ° C, low water absorption, resistant to acids, bases, solvents, alcohol, gasoline, water, oil, but do not hold HcIO and flammable.




- Polyamide (PA)
The name of the market is Nylon, thermoplastic properties, ductile at 2% -3% humidity, hard, brittle and stiff in the dry state. Color yellowish, opaque and easily colored. Able welded and glued also able to work on - ^ 40 ° C - 110 ° C.
- Polycarbonate (PC)
Thermoplastics, such as glass, capable of bouncer, capable of machining high, the shape does not change until heated at a temperature of 135 ° C, non-flammable, resistant to acids software (not concentrated), oil, gasoline and alcohol, are not resistant to alkali and solvents.
- Silicone (Si)
Heat resistant, have physical and chemical properties are very good, waterproof, capable diginakan at -90 ° C - 250 ° C, insulation material, material loading compactor for high humid areas.
- Polyurethane (PUR)
Is Elastomere, elastic like rubber, rub-resistant, scratch resistant, can be used at a temperature of -30 ° C - 80 ° C, resistant to oil, fuel, not acid resistant, alkali, solvents, hot water and flammable.
- Epoxydeharze
Elastomere, until light golden yellow color, hard and easy to work with machinery, resistant to weather changes and can be used up to 110 ° C, high electrical pengisolir, hold the soft acid, alkaline alcohol, oil, solvents, soluble in acetone and the Flammable .





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  • Quick-Build Products

    For the development of some products, such as software and many electronics products, building and testing prototype models has become such a rapid process that the design-build-test cycle can be repeated many times. In fact, teams can take advantage of rapid iteration to achieve a more flexible and responsive product development process, sometimes called a spiral product development process. Following concept development in this process, the system-level design phase entails decomposition of the product into high-, medium-, and low-priority features. This is followed by several cycles of design, build, integrate, and test activities, beginning with the highest-priority items. This process takes advantage of the fast prototyping cycle by using the result of each cycle to learn how to modify the priorities for the next cycle. Customers may even be involved in the testing process after one or more cycles. When time or budget runs out, usually all of the high- and medium-priority features have been incorporated into the evolving product, and the low-priority features may be omitted until the next product generation.
    References and Bibliography
    Many current resources are available on the Internet via www.ulrich-eppinger.net
    Stage-gate product development processes have been dominant in manufacturing firms for the past 30 years. Cooper describes the modem stage-gate process and many of its enabling practices.
    Cooper, Robert G., Winning at New Products: Accelerating the Process from Idea to Launch, third edition, Perseus Books, Cambridge, MA, 2001.
     

    Thermoplastic materials

    Two main categories of Thermoplastic materials are amorphous and Crystaline. While some materials classified in other categories and some of the material is a combination of both. Polymers like Polymethylmethacrylate, Polycarbonate and Polystyrene is an amorphous polymer chains, ie with a random molecular chain structure and become actively engaged in a wide temperature range. This means that the material is not called liquid but more accurate to say softened. And this material begins to soften so heating is carried out. Increasingly soft as the heat absorbed, until finally absorbing a lot of heat and eventually called the "melting".




    Amorphous polymers do not have a specific melting point. At low temperatures they are hard, dense, brittle and luster, at high temperatures such as rubber or leather. Temperature when the transition occurs is called the Glass-Transition Temperature (Tg), also called Point glass or glass temperature.

    In Crystaline material, regular molecular chain structure and become active only after the material is heated to its melting point. This means that these materials do not pass through a phase softened, but remained solid until heated at certain temperature and instantly melted material.



    Differences property amorphous and Crystaline


    Amorphous

    * Net

    * Low Shrinkage

    * Softened

    * The high mashed

    * Lack of chemical resistant


    Crystaline

    * Opaque

    * Depreciation high

    * Melt

    * Low Power mashed

    * Hold chemicals



    Examples of materials based on molecular structure


    Amorphous

    * ABS

    * Acrylic

    * Polyamide

    * Polyacrylate

    * Polycarbonate

    * Polystyrene

    * Polyurethane


    Crystaline

    * Acetal

    * Nylon

    * Polyester (PBT)

    * Polyethylene

    * Polyethyleneterephthalate (PET)

    * Polypropylene

    * Polyvinylcloride (PVC)



    To improve the ductile properties of amorphous glass below its transition temperature we can mix it with some elastomers. This is known as an elastomer polymers dimodofikasi into rubber. Some examples of the elastomer is Acrylates, Butyls, Fluorosilicon, Fuorocarbons Polysulfids polyurethane.

    The ability of plastics to return to his native structure after heating and then softened or melted in other words, reversible process called Thermoplastic. If we raise the temperature above the Tg of his skin then first became such as rubber along with the addition of temperature. finally at a temperature above its melting point at Crystaline become viscous fluid with a viscosity decreases with further increase in temperature. In the liquid phase resembles a plastic ice cream can be formed. Because of its recyclable plastic can then be formed up to several times, but repetition of heating and cooling causes the reduction in the quality of the plastic.

    When Thermoplastic deformed or are interested, this process is called orientation. Like the metal polymer becomes anisotropic. Specimens become more powerful and solid in the direction of pull than the transverse direction. Another important thing is the ability of water-absorbing polymer. Water makes the plastic becomes more plastic. With the addition of moisture, Glasstransition Temperature, voltage and modulus of elasticity will be lower. Dimensional changes also occur due to moisture environment.


    (Bid / multiple sources)

    High-Risk Products

    The product development process addresses many types of risk. These include technical
    risk (Will the product function properly?), market risk (Will customers like what the team
    develops?), and budget and schedule risk (Can the team complete the project on time an
    within budget?). High-risk products are those that entail unusually large uncertainties related
    to the technology or market so that there is substantial technical or market risk. The generic product development process is modified to face high-risk situations by taking steps to address the largest risks in the early stages of product development. This usually requires completing some design and test activities earlier in the process. For example, when there is great uncertainty regarding customer acceptance of a new product, concept testing using renderings or user-interface prototypes may be done very early in the process in order to reduce the market uncertainty and risk. If there is high uncertainty related to technical performance of the product, it makes sense to build working models of the key features and to test these earlier in the process. Multiple solution paths may be explored in parallel to ensure that one of the solutions succeeds. Design reviews must assess levels of risk on a regular basis, with the expectation that risks are being reduced over time and not being postponed.


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  • References and Bibliography
    Many current resources are available on the Internet via www.ulrich-eppinger.net
    Stage-gate product development processes have been dominant in manufacturing firms for the past 30 years. Cooper describes the modem stage-gate process and many of its enabling practices.
    Cooper, Robert G., Winning at New Products: Accelerating the Process from Idea to Launch, third edition, Perseus Books, Cambridge, MA, 2001.


    for STEP BY STEP GUIDE solidwork simple tutorial please visit.........
    www.solidworksimpletutorial.blogspot.com

    ---or---

  • www.solidwork-simple-tutorial.com



  • basic theory of plastic

    Plastic is an organic material formed from macromolecules and processed through a chemical process or through the synthesis of other materials. The word itself comes from the plastic plastikos (Greek) which means it can be formed. Plastics can be formed, cast or merged with another with relative ease. Plastic itself commercially daiam various forms of sheets, plates, film, rolls, and tube granulat with various cross-sectional shape. Polymer word was first used in 1866. Previous polymers made from natural organic material of animals and plants. With a variety of chemical reactions in the modified cellulose acetate cellulose, is used to for the manufacture of photographic film, sheet packaging, and textile fibers. Cellulose nitrate is also converted into cellulose for plastics, explosives, rayon and varnished. The first synthetic polymers which man is phenol-formaldehyde, a type of thermoset that was developed in 1906 called bakelit rian (the commercial name, LH Backeland, 1863-1944)


    The development of modern plastics technology began in 1920, when the raw materials needed to manufacture the polymer material is then extracted from the tin and petroleum. Ethylene is the first example of such nentah materials, and the forming polyethylene block. Ethylene is a product of the reaction between acetylen with hydrogen, while acetylen is the result of reaction between coke and methane. Similarly, polypropylene, Polyvinylchlonde, Polymethyl methacrylate, polycarbonate and others made the same way. These materials are known as synthetic organic polymer. Although in Polyethylene only Carbon and Hydrogen atoms are involved, other polymers can be combined with chlorine, Florin, sulfur, silicon, nitrogen and oxygen. The result is to make the other advantages of each polymer.

    The reason people use plastic materials as a basic material goods / tools are:
    - Easily carried or formed
    - Do not conduct electricity
    - Able to pull a fairly high
    - Low specific gravity
    - Etc.

    When compared to metal, plastic has advantages and disadvantages as follows;
    1. Profit
    a. Mild
    b. Economical in progress
    c. Corrosion-resistant
    d. Vibration damping
    e. Low heat dissipation
    f. Surface / better display. Can be recycled (except type termosett). Complex formation can be manufactured

    2. Loss
    a. Low strength
    b. Low thermal resistance
    c. Dimensions are not Stable
    d. Easy to change nature.
    e. Difficult repairs.
    f. More suitable for mass production
    g. For some types of polymers are still expensive.
    ( bid / multiple sources )



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  • Process-Intensive Products

    Examples of process-intensive products include semiconductors, foods, chemicals, and
    paper. For these products, the production process places strict constraints on the properties of the product, so that the product design cannot be separated, even at the concept phase, from the production process design. In many cases, process-intensive products are produced in very high volumes and are bulk, as opposed to discrete, goods.
    In some situations, a new product and new process are developed simultaneously. For
    example, creating a new shape of breakfast cereal or snack food will require both product and process development activities. In other cases, a specific existing process for making the product is chosen in advance, and the product design is constrained by the capabilities of this process. This might be true of a new paper product to be made in a particular paper mill or a new semiconductor device to be made in an existing wafer fabrication facility.

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  • References and Bibliography
    Many current resources are available on the Internet via www.ulrich-eppinger.net
    Stage-gate product development processes have been dominant in manufacturing firms for the past 30 years. Cooper describes the modem stage-gate process and many of its enabling practices.
    Cooper, Robert G., Winning at New Products: Accelerating the Process from Idea to Launch, third edition, Perseus Books, Cambridge, MA, 2001.


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    www.autocadsimpletutorial.blogspot.com

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  • www.autocad-simple-tutorial.com



  • French's model of the design process

    The process begins with an initial statement of a need, and the first design activity is analysis of the problem. French suggests that the analysis of the problem is a small but important part of the overall process. The output is a statement of the problem, and this can have three elements:
    • a statement of the design problem proper
    • limitations placed upon the solution, e.g. codes of practice, statutory  requirements, customers' standards, date of completion, etc.
    • the criterion of excellence to be worked to.






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  • Engineering Design Methods
    Strategies for Product Design
    THIRD EDITION
    Nigel Cross
    The Open University, Mi/ton Keynes, UK
    JOHN WILEY & SONS, LTD
    Chichester- New York. Weinheim • Brisbane. Singapore. Toronto

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  • Platform Products

    A platform product is built around a preexisting technological subsystem (a technology platform). Examples of such platforms include the tape transport mechanism in the Sony Walkman, the Apple Macintosh operating system, and the instant film used in Polaroid cameras. Huge investments were made in developing these platforms, and therefore every attempt is made to incorporate them into several different products. In some sense, platformproducts are very similar to  technology -push products in that the team begins the  development effort with an assumption that the product concept will embody a particular technology. The primary difference is that a technology platform has already demonstrated  its usefulness in the marketplace in meeting customer needs. The firm can in many cases assume that the technology will also be useful in related markets. Products built on technology platforms are much simpler to develop than if the technology were developed from scratch. For this reason, and because of the possible sharing of costs across several products, a firm may be able to offer a platform product in markets that could not justify the development of a unique technology.



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  • References and Bibliography
    Many current resources are available on the Internet via www.ulrich-eppinger.net
    Stage-gate product development processes have been dominant in manufacturing firms for the past 30 years. Cooper describes the modem stage-gate process and many of its enabling practices.
    Cooper, Robert G., Winning at New Products: Accelerating the Process from Idea to Launch, third edition, Perseus Books, Cambridge, MA, 2001.




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    www.solidworksimpletutorial.blogspot.com

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  • The Design Process Descriptive Models

    There have been many attempts to draw up maps or models of the design process. Some of these models simply describe the sequences of activities that typically occur in designing; other models attempt to prescribe a better or more appropriate pattern of activities.
    Descriptive models of the design process usually identify the significance of generating a solution concept early in the process, thus reflecting the solution-focused nature of design thinking. This initial solution conjecture is then subjected to analysis, evaluation,refinement and development. Sometimes, of course, the analysis and evaluation show up fundamental flaws in the initial conjecture and it has to be abandoned, a new concept generated and the cycle started again. The process is heuristic: using previous experience, general guidelines and rules of thumb that lead in what the designer hopes to be the right direction, but with no absolute guarantee of success.
    In Chapter 1 I developed a simple descriptive model of the design process, based on the essential activities that the designer performs. The end-point of the process is the communication of a design, ready for manufacture. Prior to this, the design proposal is subject to evaluation against the goals, constraints and criteria of the design brief. The proposal itself arises from the generation of a concept by the designer, usually after some initial exploration of the ill-defined problem space. Putting these four activity types in their natural sequence, we have a simple four-stage model of the design process consisting of: exploration, generation, evaluation and communication.
    This simple four-stage model is shown diagrammatically in Figure 9. Assuming that the evaluation stage does not always lead directly onto the communication of a final design, but that sometimes a new and more satisfactory concept has to be chosen, an iterative feedback loop is shown from the evaluation stage to the
    generation stage.
    Models of the design process are often drawn in this flowdiagram form, with the development of the design proceeding from one stage to the next, but with feedback loops showing the iterative returns to earlier stages which are frequently necessary.
    For example, French (1985) has developed a more detailed model of the design process, shown in Figure 10, based on the following activities: analysis of problem; conceptual design; embodiment of schemes; detailing. In the diagram, the circles represent stages reached, or outputs, and the rectangles represent activities, or work in progress.




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  • Engineering Design Methods
    Strategies for Product Design
    THIRD EDITION
    Nigel Cross
    The Open University, Mi/ton Keynes, UK
    JOHN WILEY & SONS, LTD
    Chichester- New York. Weinheim • Brisbane. Singapore. Toronto

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  • Adapting the Generic Product Development Process

    The development process described by Exhibits 2-2 and 2-3 is generic, and particular processes will differ in accordance with a firm's unique context. The generic process is most like the process used in a market-pull situation: a firm begins product development with a market opportunity and then uses whatever available technologies are required to satisfY the market need (i.e., the market "pulls" the development decisions). In addition to the marketpull process outlined in Exhibits 2-2 and 2-3, several variants are common and correspond to the following: technology-push products, platform products, process-intensive products,
    customized products, high-risk products, quick-build products, and complex systems. Each of these situations is described below. The characteristics of these situations and the resulting deviations from the generic process are summarized in Exhibit 2-4.

    Technology-Push Products
    In developing technology-push products, the firm begins with a new proprietary technology and looks for an appropriate market in which to apply this technology (that is, the technology "pushes" development). Gore-Tex, an expanded Teflon sheet manufactured by W L. Gore Associates, is a striking example of technology push. The company has developed dozens of products incorporating Gore-Tex, including artificial veins for vascular surgery, insulation for high-performance electric cables, fabric for outerwear, dental floss,
    and liners for bagpipe bags.
    Many successful technology-push products involve basic materials or basic process technologies. This may be because basic materials and processes are deployed in thousands of applications, and there is therefore a high likelihood that new and unusual characteristics of materials and processes can be matched with an appropriate application.

    The generic product development process can be used with minor modifications for technology-push products. The technology-push process begins with the planning phase, in which the given technology is matched with a market opportunity. Once this matching has occurred, the remainder of the generic development process can be followed.
    The team includes an assumption in the mission statement that the particular technology will be embodied in the product concepts considered by the team. Although many extremely successful products have arisen from technology-push development, this approach can be perilous. The product is unlikely to succeed unless (1) the assumed technology offers a clear competitive advantage in meeting customer needs, and (2) suitable alternative technologies are unavailable or very difficult for competitors to utilize. Project risk can possibly be minimized by simultaneously considering the merit of a broader set of concepts which do not necessarily incorporate the new technology. In this way the team verifies that the product concept embodying the new technology is superior to the alternatives.








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  • References and Bibliography
    Many current resources are available on the Internet via www.ulrich-eppinger.net
    Stage-gate product development processes have been dominant in manufacturing firms for the past 30 years. Cooper describes the modem stage-gate process and many of its enabling practices.
    Cooper, Robert G., Winning at New Products: Accelerating the Process from Idea to Launch, third edition, Perseus Books, Cambridge, MA, 2001.


    for STEP BY STEP GUIDE autocad simple tutorial please visit.........
    www.autocadsimpletutorial.blogspot.com

    ---or---






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  • Learning to Design

    An appropriate use of the 'solution-focused' approach to design is something that seems to develop with experience. Experienced designers are able to draw on their knowledge of previous exemplars in their field of design, and they also seem to have learned the value of rapid problem-exploration through solutionconjecture. In comparison, novice designers can often become bogged down in attempts to understand the problem before they start generating solutions. For them, gathering data about the
    problem is sometimes just a substitute activity for actually doing any design work.

    However, novice designers are also frequently found to become fixated on particular solution concepts. Early solution concepts are often found to be less than satisfactory, as problem exploration continues. Novice designers (and sometimes more experienced ones) can be loath to discard the concept and return to a search for a better alternative. Instead, they try laboriously to design-out the imperfections in the concept, producing slight improvements until something workable but perhaps far from ideal is attained. Sometimes it can be much more productive to start afresh with a new design concept.

    Another difference between novices and experts is that novices will often pursue a depth-first approach to a problem: sequentially identifying and exploring sub-solutions in depth, and amassing a number of partial sub-solutions that then somehow have to be amalgamated and reconciled, in a bottom-up process. Experts
    usually pursue predominantly breadth-first and top-down strategies, as recorded in the example of the expert designer's decision tree in Figure 6 (Chapter 1). Experienced designers, like any skilled professionals, can make designing seem easy and intuitive. Because skilled design in practice therefore often appears to proceed in a rather ad hoc and unsystematic way, some people claim that learning a systematic process does not actually help student designers. However, a study by Radcliffe and Lee (1989) did show that a systematic
    approach can be helpful to students. They found that the use of more efficient design processes (following closer to an ideal sequence) correlated positively with both the quantity and the quality of the students' design results. Other studies have tended to confirm this.
    From studies of a number of engineering designers, of varying degrees of experience and with varying exposures to education in systematic design processes, Fricke (1996) found that designers following a 'flexible-methodical procedure' tended to produce good solutions. These designers worked reasonably efficiently and followed a fairly logical procedure, whether or not they had been educated in a systematic approach. In comparison, designers either with a too-rigid adherence to a systematic procedure (behaving 'unreasonably' methodically), or with very unsystematic approaches, produced mediocre or poor design solutions. 
    Successful designers (ones producing better quality solutions) tended to be those who:
    • clarified requirements, by asking sets of related questions which focused on the problem structure
    • actively searched for information, and critically checked given requirements
    • summarised information on the problem formulation into requirements and partially prioritised them
    • did not suppress first solution ideas; they held on to them, but returned to clarifying the problem rather than pursuing initial solution concepts in depth
    • detached themselves during conceptual design stages from fixation on early solution concepts
    • produced variants but limited the production and kept an overview by periodically assessing and evaluating in order to reduce the number of possible variants.
    The key to successful design therefore seems to be the effective management of the dual exploration of both the 'problem space' and the 'solution space'.
    Designing is a form of skilled behaviour. Learning any skill usually relies on controlled practice and the development of techniques. The performance of a skilled practitioner appears to flow seamlessly, adapting the performance to the circumstances without faltering. However, learning is not the same as performing,
    and underneath skilled performance lies mastery of technique and procedure.









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  • Engineering Design Methods
    Strategies for Product Design
    THIRD EDITION
    Nigel Cross
    The Open University, Mi/ton Keynes, UK
    JOHN WILEY & SONS, LTD
    Chichester- New York. Weinheim • Brisbane. Singapore. Toronto