Section B - specialist technical principles Flashcards
What do you call it when you cut down a tree?
Felling
What are the two types of seasoning wood?
Kiln drying - quicker, more expensive
Air drying - cheap, slow
Both bring moisture from 200% to 20%
What does planed all round mean?
The process of using a plane to smooth the edges and sides of a plank, usually removing around 2-3mm of wood.
Give a step by step guide on how MDF is made.
-offcuts come to factory
-machines shred and dry wood chips
-wood chips and sawdust is added to a mixture of glue, resin and water
-finally the mixture is heated, pressed and extruded to make the final sheet of material.
Why is timber seasoned?
To stop the wood from shrinking and warping over time.
Name the three different types of cuts for timbre?
Through and through, quarter cut and baulk cut
What are the pros and cons of a through and through cut?
Pros = cost effect, quick, general use
Cons = can warp and twist easily
What are the pros and cons of a quarter cut?
Pros = high quality cut , used in high quality furniture
Cons = complex and expensive , creates a lot of waste
What are the pros and cons of a baulk cut?
Pros = very simple, good for posts and Beams
Cons = creates a lot of waste
What is the benefit of using a housing joint?
As the pressure is dissipated into the walls
Give 3 examples of reinforced materials?
Carbon fibre, reinforced concrete and denim jeans
What is a composite material?
A material produced from 2 or more materials with different physical and chemical properties
What is a reinforced material
Give 3 examples of composite materials
Reinforced concrete, MDF and fibreglass
What is webbing?
A strong, narrrow, closely woven fabric designed for bearing weight and especially used in ropes and straps
Give 3 examples of webbing?
Seat belt, climbing and sandals
How is plywood made?
Layers of different types of wood are glued or compressed together but with the grain turned by 90 degrees
Why is the grain rotated 90 degrees in plywood?
As it reinforces the wood and gives it multidirectional strength
What does wasting mean?
Removing material
Name 4 different types of drill bit?
Flat head drill bit, twist bit, counter sink bit and forstner bit
What is a forstner drill bit used for?
Used to drill large, flat bottomed holes
What is a counter sink bit used for?
Used to make holes for the top of the screw to sit flush with materials.
What is a twist bit used for?
Drilling holes, and Create a pilot hole to stop wood from splitting.
Give an in-depth guide to turning (using the lathe)
- diagonal lines are drawn across the crosses, at the end of each piece of wood, to find the centres
-the waste wood is removed with a suitable plane. - a tenon saw is used to cut a diagonal groove at one end of the piece of wood. This is to help the drive centre prongs to grip the wood.
-the drive centre is hammered together into position with a wooden mallet, at the grooved end, using a mallet. - the wood is then set up in the lathe, ready for turning
-the tool rest should be quite close to the wood . before turning on the lathe, spin the wood to ensure it doesn’t catch on the tool rest. - a roughing gouge is used to remove the majority of wood when Turning. Then use a scraper, gouge or parting tool for a more accurate finish.
what does a router do?
it is used to shape peices of wood with perfectly finished edges and corners.
what does a digital vernier calliper do?
used to measure external and internal distances extremely accurately.
what is beading?
long small peices of wood available in a range of lengths and styles.
( used in skirting boards)
what is a dowel?
a long, cylidrical peice of wood available in a range of diameters and lengths.
what is a veneer?
thin, paper-like peice of wood. (commonly 1.5 mm thick) used to cover peices of wood on e.g. doors, tops, panels.
what is a wood tack?
commonly used in upholstery and once used to make shoes and saddles for horses. they are short and very sharp with a larger heasd than other nails.
what are block and rigid joints?
block joint- used to join peices together. often found in flat pack furniture however dont look very good.
rigid joint- added to increase stablility and limit movement in a joint. also look nicer than a block joint.
what is a cam fastener?
used in lockers, safety boxes, cabinets and drawers. also often found in flat pack furniture. they are small screw nuts that we fasten within the furniture.
name the 6 most common joining methods.
-dowel joint (connected with dowels)
-finger joint (interlocking like fingers)
-mitre joint (connects two peices at a right angle diagonally)
-housing joint (one peice fits inside another)
-mortise and tenon joint ( like a female to male plug)
-butt joint ( two peices connected at a right angle)
what are the 6 Rs?
reduce, reuse, refuse, repair, recycles, rethink
what are the three categories of timbre?
soft (pine) , hard (oak) and manfactured board (MDF)
name 7 ways timbre can be cut and shaped.
sawed, turned, sanded, rasped, planed, pillar drilled, hand drilled.
name 6 wood finishes and what their job is.
- acrylic paint - colours wood, creates a protective coating from knocks
-wax - waterproof wood, protection fungus and insect attack, enhances natural green
-oil - soaked into timber, protect from moisture, can be coloured with steam, enhances grain
-varnish - protect from moisture, can be coloured, gloss, satin or maths finish, yellows with age
-wood stain - permanently colours would, does not protect it, results vary depending on base wood and colour - wood preservative - protects word from fungal or insect attack and prevents rot and decay, needs wrap reapplication now and again
explain why tanalising is used to preserve words?
(pressure treated wood)- to improve life expectancy and to make timber more resistant to rot, fungus, mould, insect attack and general damp weather
What are the four different scales of production and what are they?
Bespoke - made specifically to fit the need and requirtements for a user.
Batch- when a quantity of identical goods is made at the same time
mass - making large quantities of standard products
continuous - making products in an uninterrupted flow in the manufacturing line and a consistent delivery of goods.
what is FSC and what are the pros and cons of it?
forset sterwardship council - pros: secures a long term source of paper, cons: more expensive
make wood questions
describe the process of steam bending.
1) let plywood rest in hot water for 10 mins
2) glue two peices of plywood together with grain at 90 degrees
3) tape peices of wood together to keep them in place.
4) put wood in a former and clamp over night.
what is a go/no go gauge?
used to check that a hole size is within tolerance.
