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- List eight steps involved in bonding a plastic laminate to piece of plywood that has been cut to size using contact adhesive.
- Figure 8 shows the cross-section of a log.
Name the parts labelled P, Q, R and S.
State the purpose of each of the following in relation to seasoning:
(i) stickers;
(ii) steam;
(iii) fans;
(iv) vents.
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Most candidates were able to:
label the given parts of the cross-section of a log;
state the purpose of each of the given terms in relation to seasoning.
However, they were unable to list the steps involved in bonding a plastic laminate to a piece of plywood.
The expected response to question 3 is as given below:
Bonding a plastic laminate to a piece of plywood
- Prepare the surface of the plywood by removing any irregularity probably by toothing or sand surfaces dean.
- Apply the contact adhesive to the plywood surface.
- Apply the contact adhesive to the under surface of the plastic laminate.
- Allow contact adhesive to dry.
- To ensure that the sheet is placed in the correct position, place either a pin or nail or strips of wood on the plywood surface at one end or side.
- Carefully lower the plastic sheet onto the plywood surface.
- Apply pressure from the centre towards the end and side to avoid trapping bubble of air.
- Trim the edges.
The parts labelled, P, Q, R and S.
P - Pith/medulla Q - Bark/Cortex R-Cambium
S- Annual rings/Growth rings.
The purpose of each of the following in relation to seasoning.
- Stickers
- Are used to allow for free movement of air in the stack.
- Are used to allow the air to circulate.
- Steam
- To reduce excessive drying tendency.
- To reduce the wood drying too quickly/fast.
- Fans - To spread or circulate steam and warm air.
Vents - To allow movement of steam.
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