Year 10 Manufacturing (Resistant Materials)

Lesson 12 Week 12 Wood Finishes (Clock Project)

Programmes of Study Teachers Rational Lesson1 (Situation and Brief) Practical Skills Design Skills Theory and Knowledge
Lesson 2
Orthographic Drawings
Brainstorming, Cognitive Charts
and Attribute Analysis
Lesson 4
Plastics. Properties, Uses and Common Forms.
Hardwoods and Softwoods Properties, Uses and Common Forms
Ferrous and Non-Ferrous Metals, Properties and Common forms
Drawing Styles and Modelling

lesson 9

Industrial Processes - Woods Finishes

Wood Preservatives
The use of preservatives protect woods that are to be used externally from fungus and insects as well as the elements. the garden shed above has been coated in creosote which is a well known preservative.
The creosote soaks into the wood and gives a brown finish. Garden fences can also be finished in this way.

The treatment is permanent but does need to be re-applied each year. The creosote on this shed has been applied using a brush. It could have been applied using a spray.

Soaking the timber in the preservative or forcing the preservative into the timber under pressure gives the greatest penetration.

The two external doors above are made from different woods and are treated in different ways. The door on the left is made of pine and the door on the right from oak.

Paint is suitable for internal and external use. There are many types of paints available but most external paint is oil based. The wood needs to be sanded down, primed, undercoated and painted with a number of coats of gloss, egg-shell or matt paint. The wood needs to be rubbed down between each coat with wire wool or a fine abrasive paper. The door on the left has been painted.

Plastic Finishes
The door on the right has been varnished with a polyurethane varnish. The finish may be matt, gloss or eggshell. The varnish shows the grain and natural colour of the wood. The varnish produces a waterproof, transparent finish and can be used internally or externally.

The pine cabinet on the left has been waxed. The wax produces a dull finish and as varnish shows the natural grain of the wood. It can be made by shredding beeswax into turpentine. In between each coat of wax the wood needs to be rubbed down with fine wire wool. The end finish needs to be polished with a rag.

The bench on the right has been coated with oil. The bench has been made from a hardwood called teak and is finished with teak oil. It produces a natural finish. it is possible to use linseed oil but olive oil is used for wood that come into contact with food. The surface does need regular recoating.