Most candidates were able to:
- define adhesive correctly;
- explain the given terms associated with adhesives.
However, they were unable to list the types of adhesives used in furniture making.
The expected response to question 7 is as given below:
- Adhesive: is a substance used to bond two surfaces.
- Types of Adhesive:
- animal adhesive;
- protein adhesive;
- resin adhesive;
- casein adhesive;
- contact adhesive;
- polyvinyl acetate;
- urea formaldehyde.
- (i) Pot life: is the length of time the glue remains useable after
mixing.
(ii) Assembly time: (open and closed)
- Open assembly is the time allowed between applying the glue and fixing of the members of the job together.
- Closed assembly is the period during which adjustment
are possible e.g. squaring and aligning members.
(iii) Setting time: is the time it takes the glue to reach maximum
strength after being applied to the job.
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