1. WOOD SUPPLY Seasoning wood
A Freshly cut tree is 80% water. Timber must be dried to below 18% this is called seasoning
Seasoning wood
Air seasoning stacks the planks outside.

2. WOOD SUPPLY Kiln seasoning : Stacks the planks in a room.
1st Pumps in steam
then warm dry air around them.
This dry's the wood to the required level in a couple of weeks
Advantages: kills insect eggs in the timber, only takes a few weeks rather than two years, the final product will not warp in use

3. Distortions in wood due to shrinkage and swelling
Seasoned timber has increased strength, resistance to decay and stability meaning it is less likely to warp
TWIST
CUP

4. Knots in wood: Knots appear where a branch grew out of the wood.
Knots can make that part of the timber harder to cut
Knots can also fall out leaving holes
Knots can be visually appealing and can be treated
Page 280 in text book

5. Wood grain:
Read the section “grain structure and density” page 280 and make notes

6. WOOD SUPPLY Wood can be purchased in different states.
Rough Sawn. This is straight from the saw mill and has a rough surface from the large saw teeth.
PAR. This means Planned All Round. The wood has been put through a planning machine. It is smooth on all sides and is accurate to a certain size and has a slightly rounded edge.
They only need to know PER and PSE
PSE. This means planed square edge, where all 4 surfaces are planed with the edges left square
PBS. This means Planned Both Sides. The wood has been planned on both faces to make it smooth and parallel but the edges are left rough sawn.

7. WOOD SUPPLY Stock sizes
Timber is available in a variety of stock forms : Regular sections
Designers can use the standard sizes when designing products

8. WOOD SUPPLY Stock sizes
Timber is available in a variety of stock forms : Mouldings
Saves time but relatively expensive
Examples: skirting boards and decorative edging

9. WOOD SUPPLY Stock sizes
Timber is available in a variety of stock forms : Dowels
Used in model making to furniture construction. Can be used to join pieces of wood – dowel joint

10. WOOD SUPPLY Stock sizes
Timber is available in a variety of stock forms : Sheets
Mainly manufactured boards are supplied in this way but you can get sheets of veneers that are thin layers of wood “peeled” from a tree trunk
Don’t show all the veneer peeling video but shows the idea– very noisy

11. HOMEWORK
Use the internet to research the different sizes of timber that are available at a DIY store.
1. Record 4 different stock sizes and get their images
2. Explore what moulding they have available and find some images and prices to put in your research.
3. Find out what manufactured board sizes are available and record with images three different manufactured board sizes
4. Explain what the difference is between imperial sizes and metric sizes