Chapter 1 Materials & Components

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Materials & Components

Types of woods:

Hardwoods

Softwoods

Hardwoods:

Comes from deciduous trees (leaf-loosing trees).

Slow growing, making them denser.

Expensive

Examples:

Oak

Mahogany

Beech

Ash

Oak - Hardwood

Properties -

Hard, tough, durable, high-density

Uses -

High-quality furniture, garden benches, boat building, veneers

Advantages -

Finishes well

Disadvantages -

Contains an acid which corrodes steel

Problems:

Organic material and will decay over time.

In wetter conditions it will decay quicker.

Subject to condition such as dry rot and attack by pests which make it structurally weaker.

Subject to warping, bowing, cupping, splitting.

Wood contains knots which create weaknesses in the timber.

Properties:

Very fibrous

Small and compact fibres give the wood greater mechanical strength and hardness.

Dense

Softwoods:

Comes from coniferous trees (Cone bearing trees)

Sustainable

30 years for tree to reach full maturity

Examples:

Pine

Properties:

Structure is made from tube like cells making it less dense.

Prone to water damage.

Absorbs water very easily.

Mahogany - Hardwood

Properties -

Durable medium density

Uses -

Indoor furniture, interior woodwork, window frames, veneers

Advantages -

Finishes well, relatively easy to work with

Disadvantages -

Prone to warping, some tropical types can be a bit soft & fibrous.

Beech - Hardwood

Properties -

Hard, tough

Uses -

Workshop benches, children's toys, interior furniture, kitchen chopping boards & worktops

Advantages -

Turns well, finishes well

Disadvantages -

Prone to warping

Ash - Hardwood

Properties -

Tough, flexible, good elasticity

Uses -

Sports equipment, ladders, laminated furniture, tool handles

Advantages -

Flexible

Disadvantage -

Can become a bit splintered.

Pine - Softwood

Properties -

Lightweight

Uses -

Constructional woodwork (joists, roof trusses), floorboards, children's toys, garden decking

Advantages -

Nice colour & grain pattern, grows relatively quickly in comparison with hardwoods

Disadvantages -

Prone to warping, knots can fall & leave holes.

Manufactured boards:

Man-made

Waste wood is used to make MDF, chipboard

Others are veneers such as plywood.

Advantages -

Available in large sheets, so they can be used for large pieces of furniture without having to join pieces together, good dimensional stability (does not warp as much as natural timbers),

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