Section B Flashcards
what are the 4 stages of converting logs to planks
1 - felling
2 - debarking
3 - cutting
4 - seasoning (water needs to be below 20%)
what does planed all round (PAR) mean
using a plane to smooth all the sides of a plank
how are manufactured timbers made
offcuts and chips are sent to factory, shredded then dried, resin added, heated pressed and rolled into sheets
what is tension
pulling two ends of an object in opposite directions
what is compression
pushing the two ends of an object together
what is bending
arcing two ends of an object toward each other
what is torsion
twisting each end of an object in opposite directions
what is shear
when an object has pressure on it from different directions
what is a reinforced material
a material designed to resist forces
why are plywood layers put at 90 degrees to each other
to make the wood have multidirectional strength
how is plywood bent
the layers are stuck together and the edges are taped, the layers are sandwiched in a former and then clamped together for 24hrs so the glue sets
what is the difference between a tenon saw, a coping saw and a rip saw
tenon has large flat metal sheet for blade, to cut timber, straight cuts
coping has thin blade, for complex cuts because it can be turned while cutting
rip saw is big and not just wood
what is wasting (wood)
removing material to shape it
what are the 4 types of drill bit
flat head drill bit - big holes
twist bit - drills nice holes
counter sink - to allow the head of a screw to sit flush with the wood
forstner drill bit - drill a flat bottomed hole
steps for using lathe
1 - draw diagonal lines on wood to find centre and using compass add small hole in centre
2 - wood is cut with plane to be octagonal
3 - using tenon saw cut diagonal groove in other end of wood
4 - hammer wood into place in lathe
5 - rest gouge on tool rest
6 - turn on lathe
what are the main 6 stock forms for wood
plank, sheet, beading (skirting board), dowel, cladding, veneer
what are the 6 standard woodworking components
screw, nail, wood tack, dowel, hinge, joint
what is a dowel joint pros and cons
where both pieces of wood have holes in them where a dowel is put so they attach
pros - cheap, no screws/nails
cons - weak
what is a finger joint pros and cons
where both bits of wood have alternating ‘fingers’ that lock together at a right angle
pros - very strong
cons - visible seam
what is a mitre joint pros and cons
both bits of wood are cut with a 45 degree angle which is then glued together
pros - conceals corners well
cons - very weak
what is a housing joint pros and cons
where one bit of wood slots into a gap in the other
pros - simple, durable
cons - difficult to undo, needs to be precise
what is a mortise and tenon joint pros and cons
where one bit of wood has a bit sticking out the end which slots into a hole in the other one
pros - extremely strong, durable
cons - hard to construct
what is a butt joint pros and cons
the ends are stuck together
pros - easy, cheap
cons - not strong at all
what are the three categories of timber
hardwood, softwood, manufactured board
why are surface finishes and treatments applied to timber
to improve appearance and prevent water damage, and bring out grain in some cases
what are the 4 scales of production
bespoke - only made once
batch - group made at same time
mass produced - many copies made quickly
continuous - mass produced for long period of time
what is FSC
forest stewardship council, sources wood from sustainable forest by planting tree each time one is cut down
what is steam bending
1 - heat up timber so it is flexible
2 - place timber into mould and bend it
3 - leave for a while, then put in kiln to keep shape
what is quality control
checking the quality of a product and tolerances
