Processes And Techniques Flashcards
What is two-point perspective?
- Shows an object from the side with two vanishing points.
- Shows shapes receding into the distance
- Used to produce realistic drawings of an object.
Why is two-point perspective used?
- Gives the most realistic view of a product as it shows the item edge on, as we would see it.
- Communictaes overhead/suspended views well
- Represents how spatial configurations look in real life
Define lamination
The process of gluing together thin sheets or veneers to create a composite material.
Explain the composition of plywood and where it is use
Composition
- Most common form of laminate material is plywood
- Made from thin layers of wood called veneers
- Always has an odd number of veneers
- Veneers arranged with the grain at 90° to the layer above and below
- Bonded together with strong glues - usually epoxy resins.
Uses
- Indoor uses – cupboards and furniture
- Outdoor – boat building
List other laminates
- Block board
- Lamin board
How are laminates shaped?
4 Marks
- Strips of veneer are glued together and clamped in a former
- After glue drying, the material retains the shape of the former
- Used in products like chairs requiring sweeping curves
- Jigs are used to batch produce products through the lamination process - efficient for creating multiple items with consistent shapes
Explain why traditional wood joints are used and examples of them
- Strong, permanent and neat-looking
- Frame joints are right-angled, jointed frames common in furniture, boxes and many other types of assembly.
Examples
-Butt joint
- Dowelled joint
- Through housing
- Mortise and tenon
- Dovetail joint
- Comb joint
Explain why knock-fittings are used and give examples explaining where they are commonly used
- Found in flat pack furniture
- Assembled at home by customer
- Most KD fittings consist of corner blocks or bloc-joint fittings
- Usually made from a plastic such as nylon.Connecting Blocks
Examples
Connecting blocks
- Made from Polyethylene
- Used for joining sheet materials and attaching kitchen units to the
underside of the worktop for example
- Two-part blocks bolt together so enable dismantling
Furniture Connector Nuts and Bolts
- Cabinets, chairs, desks, shop equipment, tables
- For use with Joint Connector Nuts or Cross Dowels
- For use with self-assembly furniture -easily applied with an Allen key
CamLock Fitting
- Used to assemble flat pack furniture and kitchen cabinets
- Cam and Dowel parts used to pull together standard thickness board panels to give hidden fixings
Explain what a vinyl cutter is
- Computer aided manufacture (CAM) machine for cutting vinyl graphics
- Often used for graphics and company information on vehicles
- The material cut is sticky on one side, enabling it to be stuck to a surface with ease
Explain the process of vinyl cutting
5 points
- Blade has to be calibrated to correct depth, pressure, height
2.Graphics are designed on computer in a 2D format - File is sent to vinyl cutter, which moves a cutting blade on the surface of the vinyl to cut out shapes
- Waste vinyl is removed by hand
- Remaining vinyl graphics peeled from the backing material using transfer film
- Vinyl graphics are stuck to the desired surface such as a board or hard surface
Explain the positives of vinyl cutting and it’s applications
- Can be used on a wide range of materials -vinyl, paper, fabric, and even certain types of plastics - allows designers to create diverse prototypes + designs
- Precise and accurate - can create intricate and detailed designs with clean edges -ideal for creating prototypes + decorative elements
- Allows for a high degree of customization - offers unique and personalised solutions
- Relatively cost-effective - more affordable than 3D printing or CNC machining - accessible to designers with limited budgets
- Fast process - doesn’t require lengthy setup times or complex post-processing steps - speeds up product design and development process
- Minimal material waste - design is cut directly from the sheet - environmentally friendly option
Explain the negatives of vinyl cutting and it’s applications
- Material Limitations - cannot cut metals or certain types of plastics
- Limited Thickness - limited to relatively thin materials
- Can only create 2D designs
- Weeding and Transfer - After being cut, removing excess material (weeding) and transferring the design to its intended surface can be time consuming and requires skill + attention to detail
- Limited Color Options - limited to the available vinyl colors - doesn’t offer the same range as other printing or painting methods
- Maintenance - Regular maintenance to ensure they function correctly - blades need to be replaced + machine requires cleaning + calibration.
Explain the process of injection moulding
Process
1. Plastic granules poured or fed into a hopper
2. A motor turns an Archimedean screw -pushes granules along the heater section which melts them into a liquid
3. The liquid forced into mould by hydraulic ram
4. The plastic water cooled
5. The mould then opens and the unit is removed - ejector pins
Explain the pros and cons of injection moulding
Pros
- Good for mass production
- Low unit costs for high volume
- Precision moulding
- Surface texture can be added to the mould
Cons
- High set up costs
- Expensive moulds to design and make
Explain the process of blow moulding
- Injection moulded pre-form is produced
- Preform is clamped in a mould - with hollow space in the shape of the end product
- Preform is heated and hot air blown into it
- Preform takes shape of the mould
- Plastic is cooled
- Mould is opened and the product ejected
Explain the pros + cons of blow moulding (preform)
Pros
- Intricate shapes
- Hollow shapes
- Thin walls reduce weight + cost
- Good for mass production
Cons
- High set up costs
- Expensive moulds to design and make
Explain the process of blow moulding (parison)
- Plastic fed in granular
form into a hopper - A large thread turned by a
motor feeds granules through heated section - Heated section melts granules - become liquid, then forced through a die to form a parison
- Extruded parison is fed between a split
mould
- Mould is closed
- Air is forced into mould which forces the plastic to the sides, giving shape of the
bottle
Mould is cooled then removed
Explain the process of vacuum forming
- Wooden or aluminium mould
is designed (with draft angle
and small air evacuation holes) - Thermoplastic sheet
clamped above the mould - Plastic heated from above
- Once polymer is soft, mould is raised and air is ‘sucked’ out
- Polymer cools and solidifies
- The mould is lowered and the
polymer formed is removed
Explain the pros + cons of vacuum forming
Pros
- Good for batch production
- Inexpensive
- Relatively easy to make the moulds
Cons
- Accurate mould design needed to prevent webbing
- Large amounts of waste material produced
Explain the process of extrusion moulding
- Similar to injection moulding
1. Granules of plastic poured into a hopper
2. A motor turns a thread - pushes granules along the heater section which melts them into a liquid
3. Molten polymer forced through a die - forms a long tube like shape
4. Extrusion is cooled and forms a solid shape
5. Shape of the die determines shape of the tube
Explain the pros + cons of extrusion moulding
Pros
- Continuous
- High production volumes
- Low cost per unit
Cons
- Limited complexity of parts
- Uniform cross-sectional shape
only
Explain the process of rotational moulding
- Mould opens and fills
with powdered polyethylene or
polypropylene, then closed - Moulds are usually
manufactured from aluminium using CNC machines - Mould heated to 300°C
- At the same time the mould
rotates so that the powder is
forced against the wall of the
mould - Cool air is blown around the
mould by large fans -mould cools slowly + solidifies - Finished product is removed
Explain the pros + cons of rotational moulding
Pros
- Price of equipment +tooling is less than vacuum forming + blow moulding
- No seams
- Uniform wall thickness
- Metal inserts can be added to the mould
Cons
- Lower volume production
- Labour intensive
Define milling
The process of cutting away metal by feeding a
piece of work past a rotating cutter
What is the difference between routing and milling?
Similar process but routing is usually associated with wood, composites and plastics.
What do vertical milling machines shape?
- metals such as mild steel, cast steel and aluminium
- can also be used with Perspex and nylon
Advantages and disadvantages of milling
Advantages
- full size milling machines are powerful + very
accurate/precise
Disadvantages
- cutting tools are very expensive
- are broken easily if the machine operator tries to
take too deep a cut in one go
How should a miller/router used
- should be used + set up to cut away only a small amount of material each time
- the cutter passes over surface of the metal
- wide selection of cutting tools available
- made from high speed steel
What do these specific drill bits do?
1. Flat bits
2. Forstner bits
3. Auger bits
4. Countersink bits
5. Hole saw
6. Tank cutters
- deep holes in wood
- flat bottom holes in wood
- deep holes using a brace
- angled sides for screws
- large diameter holes
- circular cutters for metal
What equipment is used for turning and what are their basic processes?
- either a metalwork centre lathe or a woodturning lathe
Processes - facing off (the smoothing of an end of a piece of material)
- turning down (reducing the diameter of a piece of material)
How are lathes used?
- the work on a lathe turns
- on a metalworking lathe the cutting tools are securely fixed
- on a woodworking lathe the cutting tools are held in the
hand and rested on a tool rest - on a metalwork lathe,work is held in a chuck
- on a woodworking lathe the material is usually secured
to a faceplate or turned between centres
What is centre drilling
When a lathe is used to drill a hole
in the end of a rod or bar
How does centre drilling work?
- the work rotates in the chuck with the drill help securely in the tailstock
- If a large hole is required, a boring tool may be used - similar to the cutting tool used to turn
down outside of a metal bar, but used
internally to enlarge holes - coolant used on metalwork lathe to keep cutting tool and material cool whilst machining
How are screw heads made?
Can be cut using a centre lathe - cut from a from
a bar to produce the correct thread profile
What is knurling?
A manufacturing process typically conducted on a lathe where a pattern of straight, angled or crossed lines is cut or rolled into the material
What is parting off?
The operation of cutting a piece off by slicing a groove all the
way through material with a special parting
tool
