3. Manufacture boards
Man made woods or manufactured boards have
become important as a substitute for solid wood
over the past number of years.
The main advantages are
– Help conserve tropical forests
– They are economic alternative
– They come in large sizes with uniform
thickness
– They are stable
4. Manufactured boards
Making boards and sheets from
wood or wood products
– Veneers
– Sawdust
– Wood fibres
– Wood strips
– Wood flakes
5. Plywood
Thin strips of wood
glued together like a
sandwich
Glue is positioned
between each layer
In plywood each
layer is positioned at
90º
There are always an
uneven number of
sheets used
6. Plywood
Rotary cutting of
the veneer
Make-up of plywood
– Veneers at 90° to each other
– Odd number of layers (5/7)
7. Plywood
Advantages
– Very strong
– Stable does not warp or shrink
– Does not split easily when nailed
– Smooth uniform finish
Disadvantages
– Unattractive edge must be covered with a
veneer, moulding or a slip of wood
8. Types of plywood
WBP
– Water and Boil Proof
– Exterior grade
Marine plywood
– Boat building
– Exposed situations, roofs
9. Blockboard
Strips of softwood glued
together and faced with
veneers
Does not split easily
Can screw into the edge
Wide sheets (8’ X 4’)
10. Blockboards
Advantage
– Very strong due to different directions of
veneer
– Resistance to attack from water, heat,
chemical, fungi and insect attack
– Comes in large sizes
– Blockboard comes in large thickness
Disadvantages
– Edges need to be covered
– Surface can be easily damaged
11. Pineboard/lamwood
Made from thin softwood
strips, glued together
Makes a wide board in
softwood
Uniform thickness (12 – 25mm)
Boards tend to cup
Useful for projects
Hardwood examples can be
obtained
12. Oriented Strand board - OSB
Looks similar to
chipboard but has similar
characteristics to plywood
Wooden strands or flakes
from tree log are bonded
together under heat and
pressure by glue
Strands are aligned in 2
outer layers and an inner
core is position at 90º to
outer layers giving board
strength
14. Chipboard
Made by mixing
wood chips and
glue
This mixture is
then pressed and
pressed to form a
sheet
Plastic or veneer is
then placed over it
Used in furniture
construction
15. Chipboard
Wood chips are glued
Pressed into sheets
Often faced with wood veneer
or plastic laminate
Edges of the board need to be
covered
17. Chipboard + OSB
Advantages
– Can be veneered
– Cheap
– Uniform thickness
– Makes use of waste wood
Disadvantages
– Rough surface if not finished with a veneer
– Chipboard is weak
– Water and moisture make the sheets swell
18. MDF (Medium density fibreboard)
Very popular board material
Often faced with veneer or
plastic laminate
Made with fine wood fibres
in three layers
Need to drill into face
before nails or screws are
inserted
Fine dust is harmful
19. Medium Density Fibreboard MDF
Similar colour to
hardboard but it is much
stronger
Manufactured from fibres
mixed with synthetic resin
binder
No water is used so
pressing temperatures are
lower than for hardboard
Both sides have a smooth
finish, or boards can have
a veneer
22. Hardboard
Hardboard is made up from wood pulp
Water is added to the pulp
The mixture is then pressed under high
temperatures and the water is removed
Sheets are smooth on one side and textured on
the other
3-9mm thick
23. Hardboard
• Available in thin sheets
• One face smooth, one
textured
• Often faced with plastic
laminate
• Back of cabinets, base of
drawers
• Only used indoors
25. Name the following manufactured boards
− Pineboard
− Chipboard
26. Three layers of wood are being glued to make plywood.
Draw a sketch to show the direction in each layer.
27. The edges of chipboard look poor. Draw a sketch to show
how the edges are covered.
28. State some advantages of manufactured boards
−
−
−
−
−
−
−
−
Large sheet sizes
Cover large areas easily
Uniform thickness
Stable – no shrinkage
Do not warp
Use woods efficiently
Little waste
Often veneered over – helps to
save the rainforests
29. What do the letters WBP stand for?
Water
Boil
Proof
