Unit 8 - Working with Wood complete

Question 1

Danish oil

Answer 1

• used to replace the natural oils found in wood
• Danish oil is a mix of varnish and oils, so when the oils replenish the wood, the varnish creates a protective barrier
• it is food safe once completely dried
• can be used to prime the wood before painting

Question 2

Teak oil

Answer 2

• a blend of oils and varnishes
• can be used outside as it provides UV protection
• often used for garden furniture
• must be applied after adhesives as the high oil content prevents glue from being used

Question 3

Laminating

Answer 3

• veneers or plywood layers are used to produce a curved profile
• can be shaped using a two-part mould, wrapped in parcel tape to hold the veneers in place as they dry
• alternatively, pressure can be used in a vacuum bag, where the laminate is placed in a one part mould and encased in the bag
• a pump creates a vacuum seal and the pressure helps to shape the wood

Question 4

Steam bending

Answer 4

• steam is used to soften the wood
• steam circulates the wood, adding more water to the wood cells and softening
• once the wood has been steamed enough, it is removed and shaped using a jig or a mould

Question 5

Turning on a lathe

Answer 5

• a lathe holds and spins the workpiece to help produce an even profile
• wood can be cut, wasted, sanded or finished using a lathe

Question 6

Turning between a centre

Answer 6

• holds both ends of the wood
• allows for increased stability for longer and thinner pieces of wood
• used to make table and chair legs

Question 7

Using a chuck and a faceplate

Answer 7

• helps to hold larger work more securely
• both the chuck and faceplate support the wood from one side
• the wood is either clamped into the chuck or screwed into the faceplate
• the chuck grips the wood, with either a three jaw lock or a combination (depending on the shape of the wood)
• the faceplate screws into the wood through a paper separator which allows for easier removal

Question 8

Performance characteristics

Answer 8

grain pattern and direction
surface defects
warpage and shrinkage
splitting
joining
forming
machining qualities
resistance to decay and moisture
toxicity

Question 9

Seasoning

Answer 9

• removes moisture from the wood through air or kiln drying
  improved properties
• stronger and more stable
• less likely to decay or corrode
• can absorb preservative better

Question 10

Coach bolts

Answer 10

• Coach bolts can be identified by the square section under the domed head
• requires a pre-drilled hole
• the square section embeds itself into the wood and prevents the joint from being removed
• it is virtually impossible to remove the joint from the domed head and requires tools to fully remove
• used for children’s toys

Question 11

Knock down fittings - 3 types

Answer 11

Modesty blocks
CAM fittings
Coach bolts

Question 12

Pressure treatment

Answer 12

6 mark answer
1. an antimicrobial copper-based preservative is used to preserve the wood for longer and prevent decay
2. the timber is placed into a chamber
3. a vacuum is used to remove the air from the wood cells
4. the chamber is then filled with the anti-microbial preservative
5. hydraulic pressure forces the preservative into the wood before a second vacuum removes any excess preservative
6. finally, a low pressure draws the preservative fully into the wood before it is left to dry and removed from the chamber

Question 13

Milling

Answer 13

• used for CNC manufacturing
• allows for mass production with consistency and quality control across products
• milling moves the components up and down, working laterally
• the rotating cutting tools are often made from strong metals such as tungsten carbide, which makes them suitable for cutting almost all materials

Question 14

Routing

Answer 14

• uses versatile cutting tools
• a router can be used to machine profiles and cut out slots and holes
• router bits can be used to create a profile, with sculpted blades to remove materials and a follower wheel ensures the bit won’t go too deep

Question 15

Acrylic varnish

Answer 15

• milky white when applied but dries clear and quickly
• non-toxic (no VOCs) and essentially odourless
• durable but not particularly resistant to solvents
• often used on top of paints for an additional layer of protection

Question 16

Wax

Answer 16

• easy to apply
• natural/unnoticeable finish
• provides limited protection and must be reapplied often, requiring several coats
• waxes are generally food-safe and non-toxic

Question 17

Colour wash

Answer 17

• provides a rustic, almost vintage appearance
• solely used for aesthetic purposes but provides no protection
• applied to the materials surface before being wiped off so that the woods natural grain remains exposed

Question 18

Stains

Answer 18

• colours the wood but leaves the wood grain exposed
• solely provides an aesthetic finish, and provides no protection
• available in an wide array of colours

Question 19

Water-based paints

Answer 19

• provide an opaque finish compared to varnishes or oils
• low levels of VOCs
• easy to use and clean up, however less protective than a varnish would be
• large variety of colours available
• often used alongside a primer and a base coat (since paint is not protective enough on its own)

Question 20

Polyurethane varnish

Answer 20

• polyurethane varnish is particularly durable and resistant to heat, water and chemicals
• often used on flooring
• can become yellow due to UV exposure so it is not the most visually pleasing finish
• lustrous finish
• solvent based varnishes contain high levels of VOCs compared to water-based varnishes, which are far more environmentally friendly

Question 21

Nuts and bolts

Answer 21

• can be used as a temporary or permanent joint
• can be used to join dissimilar materials
• available with a variety of heads and styles for different projects

Question 22

Wood screws

Answer 22

• can be used to join dissimilar materials
• made from mild steel and coated with a non-corrosive metal
• available in a variety of styles (countersunk, twin drive and self-tapping)
• easy to install with a drill but may require a pilot and clearance hole to prevent splintering

Question 23

Stock forms of wood

Answer 23

PAR - Planed all round
PSE - planed square edge
edges are squared with a planer thicknesser
Rough-sawn - sold in the same way it has been cut
Manufactured board

Question 24

Modesty blocks

Answer 24

• used for edge-to-edge joints such as connecting panels
• and whilst they are easy to use, they are not particularly aesthetically pleasing, so they would not be used in a place where they are obvious (hidden fitting)

Question 25

CAM fittings

Answer 25

- requires pre-drilled holes and preparation of wood - however, once the hole has been cut, the joint can be assembled easily with a screw-driver and therefore does not require complex machinery

Question 26

Barrel nut and bolt

Answer 26

- excellent strength - can be easily tightened with an Allen key - made from two components - the bolt that goes through the wood and the nut which stabilised the joint