Timbers- Sources and Origins Flashcards
Trees are a………………
Primary Source
How much of the land is covered in forests
30%
Where do softwoods mainly come from
Cool northern parts of Europe, Canada and Russia
Where are hardwoods grown
Central Europe, West Africa and Central + South America
What is FSC
International organisation dedicated to promoting responsible management of world forests
What do FSC ensure
Forests are replanted once trees have been cut down , so an ethical and environmentally way
How long does softwood take to grow
30 years
How long do hardwood take to grow
80-100 years
Once felled the logs are transported to the………………where they are converted into usable planks
Saw mill
What is a baulk cut
Simples form of conversion
Trunk is cut into a square
This removes the bark and opens up the trunk
Lot of waste
What is a baulk cut used for
Beams in framed buildings
What are through and through cuts
Most popular form of conversion Involves cutting trunk into planks Simple and cost effective Can lead to wrapping and twisting Commonly used for softwoods
What is through and through cuts used for
General joinery purposes
What is a taginental cut
trunk is cut tagintelialy to the circular trunk
Produces an attractive gran pattern
Wood less likely to wrap or twist
Can be used for both HW and SW
What are tangental cuts used for
Furniture or where the grain is important
What is a quarter cut
Complex mix of conversion produces a lot of waste Expensive Big impact on environment Trunk is cut radial from the centre Generally used for expensive hardwoods
What are quarter cuts used for
High quality furniture
Newly converted timber contains a lot of………..and is known as green timber
Moisture
What does high water in timber mean
Wood difficult to saw or plane
Heavier to transport
Wrap and twist and split if left in this state. Also vunvrable to rotting and insect attack
How do you reduce the moisture content in timbers
Seasoning
What is air seasoning
Aim to reduce the moisture of the wood by letting air flow around it in a controlled way
Cost effective but takes a considerably longer time than kiln seasoning, it can take a year to season a 25mm thick plank of wood
How does air seasoning work
Planks are carefully stacked inside a building that has a roof but open on all sides
The roof will keep off the rain and snow but the open sids allow the air to circulate around the boards
The planks are separated by stickers and the stack of board is kept pff the floor by being placed on brick piers
As the air flows around the stack it will very slowly dry out the planks
What is kiln seasoning
Reduce the moisture content of the wood by gradually reducing the moisture content of steam that is fed into the kiln
How does kiln seasoning work
A stack of timber is mounted onto a trolley that is wheeled into a kiln
The kiln is fully enclosed and has steam fed into it
As the moisture content of the steam is reduced it dries the timber
This is significantly quicker than air seasoning
it is controllable but has a higher financial and environmental cost
Manufactured boards are……available
Readily
How are plywood and chipboard formed
Plywood and chipboard by glueing wood layers or wood fibres together
Often use waste wood
Plywood - gluing 3 or more veneers of wood together at 90 degree angles from the previous alter to increase strength
Chipboard- gluing wood chips together
How is MDF made
Competing wood particles and gluing them together
What is Aeroply wood
MDF - type that comes in thinner sheets
What does Brio use to manufacture their children’s toys
Beech
What is chipboard used for
Flat pack furniture for it’s density perfect for CNC machining due to it’s lack of grain and it can have a decorated veneer added from protection from moisture as chipboard is impermeable
Why is Brio made out of beech
Tight grain - can withstand getting dropped or chewed
Takes paint well
Tough
Durable
Wood is………..which means it can absorb moisture which can affect it in various ways
Hygroscopic
What can wood that is drying out do
Wrap Twist Bow Cup If the drying out process is not managed
Wood that is venerable to moisture will be prone to….
Rot
What is the best material for marking out wood
Soft lead pencil - nit score the surface
the steel rule is more………and less likely to snap or break
Durable
What is a try-square
Will produce an accurate 90˚ angle line and will improve the accuracy of your work when marking out
Want is a hand saw used for
Cutting thick pieces of wood or large sheets
Cuts generally quickly but produces an coarse, rough edge
Not as accurate as a tenon saw
What is a tenon saw used for
Commonly used saw in the workshop
Accurate straight lines
Smooth cut
What is the coping saw used for
Cutting curves in wood
Cuts fine cuts but not easy to control and the blades are fin so easily broken, but the saw design mans that they can be easily replaced too.
What is a surform or a rasp
Similar to a file but has much coarser teeth
What is a wood plane
Slice thin shavings of wood
All panning should be done in the same direction as the grain of the surface will tear.
What are the Jack planes used for
Used to flatten woods and smooth the edges
A fornser buit will produce a ………., ……..hole with a ……..bottom
large
Clean
Flat
Hole saw will produce a……hole but the finished hole will not be as clean and it will cut all the way through the material
Large
What are temporary joints
Joints that can be taken part such as screws nuts and bolts
What are permanent joints
Joints such as glued joints
What is a carcase joint
e.g butt joint - easy to produce but not praticualy strong
What are stool joints
These should be used to connect a leg rail such as stools, tables and chairs
What is frame construction
Used to produce panels, door frames and window frames
Mortise and tendon joint might be used for greater strength
What is PVA
Most popular wood working glue
Good amount of slip time and gives a very strong bond
Takes 24h to dry fully
What is contact adhesive
provides an almost instant joint
Spread thinly over a wood
Not as strong as PVA
Irritant and highly flammable
What are timber going components
Increase the strength of a structure or add functionality of a product
What are wood screws used for
Join two pieces of timber together
Can be removed easily to dismantle parts
What are wood screws usually made of
Steel coated in Zinc to prevent corrosion
Hinges are used where a part needs to move in a…..
Arc
What is a Butt hinge
Most widely used
Jewellery boxes
Used on doors but usually recessed into the wooden surface
Needs to be precisely aligned
What is a Concealed Hinge
Used in kitchen and cabinet doors
Usually sprung so it can self close
Easy to adjust to help alignment of doors
What is a Piano Hinge
Like a Butt Hinge but comes in one long length which can be cut to size
Used on lids such as a piano
What is a Flush Hinge
Fitted between a door and a frame like a Butt Hinge but not usually recessed
Easier to fit
Looks less attractive
What is a knock down fitting
Those that can be put together easily with a few basic tools
Often supplied with flat pack furniture
What is a corner block
Simple way to join two boards together at 90˚
The block fits into the corner and 3 screws are drilled in
Easy to use but less attractive because they are very visible
What is a Cam Lock
Stronger and more attractive way of joining a cabinet together
A leg is fitted into a hole at the end of the shelf
A cam is fitted into a larger hole and drilled into the surface of the shelf
As the cam is rotated, it grips and holds the cabinet against the shelf
What is a Scan fitting
A way of joining two parts at 90˚
An aluminium barrel is fitted into a pre drilled hole in the side of the frame
Allan key then used
What is a corner plate
Quick way to join a table leg to a frame
The plate is screwed not the two parts and pulls tight
What shapes are timber generally supplied in
Planks
Boards
Strips
Squares
Timber generally comes……………..straight from the saw mill but sometimes they are given a smooth surface
Rough sawn
What is Planned All Round (PAR)
All the sides and edges are planned square, straight and level leaving a smooth finish
What is Planned Both Sides (PBS)
Both sides are planed but not the edges they are left rough sawn
What is Planed Square Edge (PSE)
Only one edge is planed accurately
What is Rough Sawn
The wood has a rough surface provided by a circular ban saw although they are generally straight and level
Planed timber is more………….
Expensive
