DT Flashcards
1
Q
Compressive strength definition
A
the capacity of a material to withstand loads
2
Q
Tensile strength definition
A
The ability of a material to stretch without breaking/snapping
3
Q
Toughness meaning
A
The ability of a material to absorb sudden shock without breaking or shattering
4
Q
torsion definition
A
Force of an object being twisted
5
Q
What’s a beam’s purpose?
A
supports a structure’s weight
6
Q
What force do struts act against?
A
Compression
7
Q
What force do ties act against?
A
Tension
8
Q
Frame structure definition
A
The fitting together of pieces (eg beams, ties and struts) to give a structure its strength
9
Q
What is a shell structure?
A
Structure that gains its strength by the way its shaped
10
Q
Measuring
A
Estimation, precision and creating designs ideas using CAD for accuracy
11
Q
Cutting and shaping
A
Selecting the correct tools and machinery for specific processes
12
Q
Fabrication
A
• Joining of materials
• gluing/assembling of materials and quality control at each stage
13
Q
Finishing
A
Accuracy of product in relation to form, function and user.
14
Q
Material properties definition
A
The characteristics of a material and how they help it function
15
Q
Wind power definition
A
• When wind movement is harnessed to generate electricity
• Eg on windy days, propellers in wind turbines spin a generator to generate electricity
16
Q
Solar power definition
A
Conversion of energy from sunlight to electricity eg solar panels
17
Q
Hydro power definition
A
• When the force of moving water is harnessed to generate electricity
• Eg as dams release water it spins a turbine connected to a generator to produce electricity
18
Q
Geothermal power definition
A
• When heat produced in the Earth’s core is harnessed to generate electricity
• Eg geothermal power plants use the steam’s heat to drive an electrical generator
19
Q
Biomass energy
A
• When organic matter is used as fuel to generate electricity
• Eg wood is burned to power central heating systems
20
Q
Reduce definition (6Rs)
A
To cut down on the amount of products and services you use
21
Q
Reuse definition (6Rs)
A
Taking a product and changing its purpose for something else
22
Q
Rethink definition (6Rs)
A
Designing in a way that considers people and the environment
23
Q
Repair definition (6Rs)
A
Fixing a product that doesn’t work properly
24
Q
Refuse definition (6Rs)
A
deciding not to use a material if it’s not needed or has a negative impact on the people or environment
25
What are the 6Rs?
Reduce, reuse, recycle, repair, rethink, refuse
26
Hard wood (loses/keeps their leaves)
Loses their leaves
27
Soft wood ________ their leaves
Keeps their leaves all year
28
Plank meaning
Long piece of wood
29
Moulding
when a material is shaped from a mould template
30
Methods of cutting and shaping wood
File, drill, sand, plane
31
Hardwood characteristics
• Weather resistant
• The water repels during rainfall
• From deciduous trees
32
Softwood characteristics
• Not weather resistant
• Absorbs the water during rainfall
• From conifer trees
33
CAD
• Computer Aided Design
• Computer software used to develop design ideas
34
CAM
• Computer Aided Manufacturing
• Computer - controlled machinery used to manufacture a product
35
Pros of CAD
• Increased accuracy compared to hand drawing
• Saves time (no prototype to build)
• Can be sent anywhere
36
Cons of CAD
• Training is needed which requires time and money
• Work can be lost if not saved
37
Types of coatings
• Wax
• Stain
• Varnish
• Oil (sinks into the surface)
• Paint (covers the surface)
38
Manufactured board examples
• Plywood
• MDF
• Chipboard
• Hardboard
• Veneer
39
Plywood definition
• Thin layers of wood veneer glued together at right angles
• Used in furniture and structure
40
MDF (medium density fibreboard)
• Small particles of wood that have been compressed with a random orientation for a solid finish
• Absorbs moisture therefore not suitable for outdoors
41
Examples of wood stock forms
Sheets, mouldings and planks
42
What stock forms does MDF come in?
mouldings and sheets
43
What impact does MDF have on the environment?
• Made from leftover wood fibres reducing waste and saving trees
• Isn’t biodegradable and would release poisonous chemicals if disposed of incorrectly
44
The 2 categories of plastic
Thermoplastic and thermoset
45
Difference between thermoplastics and thermosets
Thermoplastics can be heated whereas thermosets can’t due to its strong covalent bonds
46
Plastic’s source of origin
Crude oil
47
Stock forms of plastic
Sheets, extrusions, plastic polymers
48
Stock form definition
The form a material is sold in
49
Methods of cutting and shaping for plastic
Blow moulding • vacuum forming • injection moulding • heat cutting • laser cutting
50
Finishes for plastic
Matt or gloss however it doesn’t require a finish
51
Why do plastics not need a finish?
They don’t rot or corrode
52
Mechanism meaning
When components work together to make a product function
53
What are the 4 types of mechanisms?
CAMs, linkages, levers and gears & pulleys
54
Linear movement
Movement in a line going in one direction
55
Oscillating movement
swinging motion going backwards and forwards
56
Rotary movement
Going round and round in circles
57
Reciprocating movement
Going up and down / in and out
58
What 2 movements are involved between the cam profile and follower?
Rotary is converted into reciprocating
59
Types of cam profiles
Drop (snail), heart, pear and eccentric (circular)
60
Plastic’s impact on environment
• Difficult to dispose of and can release poisonous chemicals
• Manufactured from crude oil (greenhouse gas emissions released)
61
How does a linkage mechanism work?
Combination of levers connect to move an object or change direction of a force eg bikes
62
Mechanical Advantage
When the force of a mechanism is multiplied to make things easier for the user
63
characteristics of a 1st class lever
The fulcrum (pivot) is in the middle of the effort and load (eg see saw)
64
characteristics of a 2nd class lever
the load is in between the fulcrum and effort (eg wheel barrow)
65
characteristics of a 3rd class lever
the effort is in between the fulcrum and load (eg fishing rod and baseball bat)
66
Effort meaning
Force or energy applied
67
Pivot meaning
Point of rotation
68
Load meaning
Object that is being moved
69
How do gears work
Its teeth interlock with other gears to rotate and change the speed or power of an object
70
Tolerance meaning
Clearances in mechanisms to allow movement with minimal friction
71
Clearance meaning
small gaps between moving parts that allow for smooth movement
72
extrusion meaning
When a material is forced through a small opening to shape it
73
Smart material meaning
Materials with the ability to change their properties depending on a change in their surroundings.
74
Examples of smart materials
• Photochromic paint (which changes colour when exposed to light)
• Reactive glass (changes transparency when current flows through)
• Shape memory alloy (programmed to remember original shape and made from nickel and titanium)
75
Veneer meaning
A thin decorative covering of fine wood applied to a coarser wood
76
Adhesive meaning
A substance which bonds the surfaces of materials together (eg glue)
77
Malleable
Describes materials that are able to bend or shape easily
78
Why is nature studied as a way to develop new materials?
• How nature adapts to its environment provides a source of inspiration for designers to mimic its functionality • (Eg The way birds fly inspired design of aircrafts)
79
Why are smart materials used in the fashion industry?
To inspire new trends and lead the market increasing amount of profit
80
What are components?
They’re universal and tend to be bought as it’s designed by specialists • Used to assemble and install fixtures and fittings
81
What are fixtures and fittings?
**Fixtures** - Items attached or fixed to property
**Fittings** - Not attached to property and can easily be removed
82
Examples of fixtures and fittings
**Fixtures** - Sinks, ovens and radiators
**Fittings** - Pictures and furniture
83
What are nails?
Small, pointed metal fasteners used to join materials together by friction
84
What are screws?
Metal fasteners that use rotational force to tear into a material and hold materials together
85
What are nuts and bolts?
Components that lock together along a threaded shaft
• They’re precise and have minimum tolerance
• (Semi permanent fasteners)
86
What are knockdown fittings?
• A type of fitting that can be put together easily by using basic tools • (Often used in flat-pack furniture)
87
What are permanent fasteners ?
• Components that permanently join 2 materials together and can’t be removed once installed
• Eg Nails permanently attach a frame to wall
88
What are semi permanent fasteners?
Components that hold objects together but aren’t permanently fixed (Eg Nuts and bolts)
89
Batch production meaning
When a certain amount of identical products are produced (eg clothing)
90
Mass Production
When a large amount of products are produced at a time (in order to meet demand eg phones)
91
Continuous production
Production that occurs every day non-stop (eg newspapers)
92
JIT (Just In Time) Production
Made in response to an order instead of being produced beforehand (to reduce money lost eg Ferraris)
93
Prototype / First Generation Model meaning
An early sample or model of a product built to test a concept
94
Describe the benefits of a Production Line
• Workers specialise in one aspect (increasing efficiency)
• Increases the speed and production rate
• Reduces waste
95
Jigs function
They hold something in place in the process of production to increase accuracy
96
QC meaning
• Stands for Quality Control
• Procedures or tests carried out during manufacturing to check for quality
97
Tessellation meaning
Repeated pattern of geometric shapes with an exact fit
98
Nesting meaning
fitting irregular shapes as close together as possible to minimise waste
99
Template meaning
A mould or pattern used as a guide to make something
100
What is CAD CAM?
Using a computer to make a drawing which will be interpreted by a machine eg laser cutters
101
What is a 3D printer?
• A method of constructing 3D objects using CAD where layers are built up
• Also referred to as additive manufacturing
102
What is a CNC router?
• It’s an acronym for Computer Numerate Control
• A spinning drill that works on 3 axes (x,y,z) and cuts into a material
103
What is planned obsolescence?
• Designing products to break quickly or become obsolete (out of date) to encourage the sales of new products
• Eg mobile phones or vehicles
104
Market pull definition
When the market encourages firms to produce new technology to meet demands eg camera development
105
Technology push meaning
When technology advances enough to develop new products before consumers demand for it (eg smartphones)
106
Ergonomics meaning
• The study of how products are designed to minimise effort and discomfort
• eg how a person rests on the back of a chair
107
Anthropometrics meaning
• How a product suits a person’s size using body measurements
• eg key sizes on a keyboard
108
Examples of ergonomic and anthropometric design
• Fender’s electric guitar has curves on both of its sides to fit around user’s stomach or their legs
• Tuning pegs are all on one side therefore it’s easier to access
• Sportswear are lightweight, breathable and don’t restrict body movement
109
Importance of designers using ergonomic and anthropometric data
• The product becomes suitable for how the user functions (maximising productivity)
• Attracts the market as the product has a personalised design (which would increase revenue)
110
What does green represent in safety signs?
• They direct and lead people to safety. • Eg fire exits
111
What does blue represent in safety signs?
• They are mandatory signs
• Usually give information
• Eg wear goggles
112
What does red represent in safety signs?
• They are mandatory signs usually meaning ‘no’
• Eg no entry
113
What does yellow represent in safety signs?
• They are warning signs and alert us to danger
• Eg radioactive chemicals
114
How does a pulley mechanism work?
• A wheel on a fixed axle with a groove in it to guide the rope
• The rope is attached to the load
• The pulley changes the direction or the amount of the force needed to lift the load
115
Explain input - process - output
**Input:**
• The force applied on the mechanism
• Eg turning a crank ; pressing a button
**Process:**
• Physical interactions within the mechanism converting the input to output
• Eg cams rotate causing the followers to move
**Output:**
• The resulting force / movement produced by the mechanism
• Eg lifting a weight using a pulley
116
What are the 4 motions?
• Linear
• Oscillating
• Rotary
• Reciprocating
117
Examples of hardwood
• Beech
• Oak
• Teak
118
Examples of softwood
• Pine
• Spruce
• Fir
119
Examples of plastic
• Polypropylene (PP)
• Nylon
• High density polyethylene (HDPE)
• Low density polyethylene (LDPE)
120
Hardness meaning
The ability of a material to resist scratching, wear and tear, and indentation
121
Laser cutting CAM process
• Takes info from the computer
• Follows x and y coordinates
• Burns the material instead of cutting it
• Red lines informs the machine to go slow
• Black lines informs the machine to go fast and etch through the material
122
Two categories of metal
Ferrous and Non - ferrous
123
Ferrous meaning
Metal that contains iron and therefore can rust/oxidise
124
Non - ferrous meaning
Metal that doesn’t contain iron so won’t rust
125
Metal source of origin
Rocks/Ores
126
Stock forms of metal
• Sheets
• Girders
• Tubes
• Bars
• Nuggets
• Beams
127
Methods of cutting and shaping metal
• Water - jet cutting
• Plasma cutting
• Laser cutting
• Drilling
• Filing
• Sawing
128
What is an alloy?
A mixture of metals to improve chemical properties
129
Examples of alloys
• Brass - An alloy of copper and zinc
• Steel - An alloy of iron and carbon
130
Finishes that can be applied to metals
• Paint dip coating
• Paint powder coating (using static charge)
• Electroplating
• Greasing
• Oiling
131
Metal’s impacts on the environment
• Metal cycling preservers natural resources and reduces the emission of greenhouse gases
• Metal extraction however may require deforestation which erodes the soil and decreases levels of biodiversity
• Scrap metals can release toxic chemicals and contaminate the ground
