PARTS OF A ROOT

UNIT 4. WOOD

VOCABULARY

A
Ash:fresno


B
Birch: abedul
Beech: haya
Branch: rama
Bark: corteza
Broadleaf:hoja ancha

C
Chesnut: castaño
Cork: corcho

D
Deciduous tree: arbol de hoja caduca

E
Elm :olmo
Evergreen tree: hoja perenne

F
Fir:abeto

G
Growth rings: anillos de crecimiento

H
Heartwood: duramen (wood that has died)
Hardwood: Madera dura

L
Leaf: hoja
Leaves: hojas

N
Needle: acícula

O
Oak: roble

P
Pine: pino
Poplar: chopo

R
Roots raíces

S
Stem:tallo
Seed: semilla
Steel: acero
Sapwood: albura (living Wood)
Softwood: Madera blanda
Sap: savia

T
Timber: Madera de construcción
Tree: árbol
Trunk: tronco

W
Wood: madera
Wooden: de madera (A wooden chair)
Walnut: nogal

DEFINITION OF WOOD

Wood is a raw vegetal material. It comes from trunks of trees and branches. It is composed of:
- Cellulose fibres.
- Lignin

PROPERTIES OF WOOD

-Physical Properties:
- Hardness
- Density
- Electrical insulator
- Thermal insulator
- Porosity

-Ecological Properties:
- Renewable
- Biodegradable
- Recyclabe
- 

HARDWOODS AND SOFTWOODS

Hardwoods and Softwoods

There are two main groups of timber producing trees used commercially: softwoods and hardwoods.

Softwoods

Softwoods are coniferous trees. They are 'evergreen'.

Their general characteristics are:Straight, slender.

The crown is narrow.It has needle like leaves.The fruit is a cone.

Hardwoods

Hardwood trees are broadleaf and generally deciduous.
The general characteristics are:wide, round crown.

The leaves are broad.Its fruit may be: nut, berries, chestnuts.

PARTS OF THE TRUNK

PARTS OF A TREE

EXERCISE

CLICK ON  http://visual.merriam-webster.com/plants-gardening/plants.php


COPY THE NAME OF THESE EXAMPLES AND TRANSLATE INTO SPANISH

BROADLEAVED TREES I                

BROADLEADLEAVED TREES II      

CONIFERS                                        

WOOD- ACTIVITIES

COMPLETE THE FOLLOWING ACTIVITIES:

1. What are the two main substances that wood is composed of?

2. If we cut a tree, in the cross section we can see these different five parts. Write  and draw them.

3. - The .................. are the lines in pieces of wood.
    - A ...................... is the main part of the tree without branches after cutting it.
    - The ...................... is the part  that protects the tree from wind, rain, insects, etc.
    - A ....................... is a small branch.
    - The singular of leave is ..................


4. True or false?
         - Wood is denser than water.
         - Wood is a good thermal insulator.
         - Wood is a good electric conductor.
         - Wood is not a biodegradable material.

5. Write the seven steps to process wood (from cutting the tree to plane it).

6. Write three characteristics of hardwood and  three of softwood.

7. Write four examples of hardwood and four of softwood.

8. What are the four types of prefabricated wood products?
     

TYPES OF SIMPLE LEAVES

TYPES OF LEAVES

PARTS OF A LEAF

HOW TO PROCESS WOOD

The process starts with the extraction of the log (raw material) from the forest and ends with the production of planks.

STEPS

1. Cutting

2. Pruning

3. Transport

4. Removing the bark

5. Sawing

6. Drying

7. Planing

STRUCTURE OF A FLOWER

HARDWOOD Vs SOFTWOOD

	HARDWOOD	SOFTWOOD
DEFINITION	Comes from deciduous trees that drop their leaves every year.	Conifer trees have needles, normally do not lose them. Evergreen
EXAMPLES	Examples of hardwood are  teak, walnut, oak, ash, elm, poplar, birch, maple etc.	Examples of softwood trees are pine, spruce, cedar, fir, larch, etc.
COST	Hardwood is typically more expensive than softwood.	Softwood is typically less expensive compared to hardwood.
GROWTH	Hardwood has a slower growth rate.	Softwood has a faster rate of growth.
CHARACTERISTICS	Wide, round crown. Leaves are broad. Its fruit may be: nut, chesnut and berries.	Straight, slender. The crown is narrow. The leaf is a needle. The fruit is a  cone
COLOR	Dark	Light
STRUCTURE	Non - resinous and close grained	Resinous

TYPES OF COMPOUND LEAVES

JOINING PLASTICS

A.  TEMPORARY JOINTS

                    - Nut and bolt


                    - Standard screw


                    - Double ended screw



B.  PERMANENT JOINTS

                                                                                -  Adhesives

                 - Soldering

SHAPING AND FINISHING TECHNIQUES

                 We can use different tools and machines to finish the plastic objects that we have made.

                 Principal techniques are cutting, perforating, trimming and filling.


a. CUTTING
                          - Cutter
                          - Scissors
                          - Steel bit
                          - Coping saw
                          - Power saw (Jig saw)
                          - Power press
                          - Hot metal thread trimmer

b. PERFORATING
                    
                          - Drill bit

c. TRIMMING AND FILLING

                          - File
                          - Rasp

FORMATION TECHNIQUES OF PLASTICS

1. EXTRUSION

2. LAMINATION

3. VACUUM FORMING Vacuum forming

4. MOLDING
            - Injection Molding    Injection molding

            - Blow Molding Blow molding

            - Compression Molding through compression

PLASTIC MATERIALS

Plastics

CLASSIFICATION OF PLASTICS

- THERMOPLASTICS

            When we heat them, they become soft, which allows them to be formed into different shapes.
            The heated and cooling process can be repeated many times.

                                 - PVC
                                 - PS
                                 - PE
                                 - PP
                                 - Methacrylate
                                 - Teflon
                                 - Cellophane
                                 - Polyamide (Nylon)


- THERMOSETTING  PLASTICS

             When heated, they become soft and can be shaped. When cooled, they cannot be remoulding by applying heat.

                               - Polyurethane
                               - Phenolic resins
                               - Melamine
                               - Polyester resins

- ELASTOMERS

                    Made by vulcanization: mixing sulphur and rubber, and heating to 160ºC.

                              - Natural Rubber
                              - Synthetic rubber
                              - Neoprene
                              - Silicone

FABRIC MATERIALS

Adam Knits

N

atural fibres are greatly elongated substances produced by plants and animals that can be spun into filaments, thread or rope. Woven, knitted, matted or bonded, they form fabrics that are essential to society.

Like agriculture, textiles have been a fundamental part of human life since the dawn of civilization. 

While the methods used to make fabrics have changed greatly since then, their functions have changed very little: today, most natural fibres are still used to make clothing and containers and to insulate, soften and decorate our living spaces. Increasingly, however, traditional textiles are being used for industrial purposes as well as in components of composite materials, in medical implants, and geo- and agro-textiles.

Plant fibres Plant fibres include seed hairs, such as cotton; stem (or bast) fibres, such as flax and hemp;leaf fibres, such as sisal; and husk fibres, such as coconut.	Animal fibres Animal fibres include wool,  hair and secretions,  such as silk.
Abaca - Coir - Cotton - Flax - Hemp - Jute - Sisal -	Alpaca wool - Angora wool - Camel hair - Cashmere - Mohair - Silk - Wool -

PLASTIC. CLASSIFICATION

There are two main types of plastics and these are named Thermoplastics and Thermosetting Plastics.

Thermoplastics are made up of lines of molecules with few cross linkages. This allows them to soften when heated and to be bent into a variety of shapes and forms. They become stiff and solid again when cold. This process can be repeated many times. The bond between the molecules is weak and become weaker when reheated, allowing reshaping. Thermoplastics tend to be composed of 'long chain monomers. They can be recycled.

Thermosetting Plastics are made up of lines of molecules which are heavily cross linked. It creates a rigid molecular structure. They may be heated the first time and shaped but they become permanently stiff and solid. They cannot be reshaped again. The molecules of these plastics are cross linked in three dimensions and this is why they cannot be reshaped or recycled

PLASTICS

                                    DEFINITION OF PLASTIC

Plastics are man-made materials. Plastics have taken the place of traditional materials like woods and metals.

Plastics differ from other materials largely because of the size of their molecules. Most materials have molecules made up of less than 300 atoms, plastics contain thousands of atoms. We call them Macromolecules.

Some plastics are derived from natural substances such as animals, insects and plants but most are man-made. These are named Synthetic Plastics. The first plastic based on a synthetic polymer was made from phenol and formaldehyde, with the first viable and cheap synthesis methods invented by Leo Hendrik Baekeland in 1909, the product being known as Bakelite.

Most synthetic plastics come from crude oil but coal and natural gas is also used. 

Monomers are chemical substances consisting of a single molecule. Thousands of these are linked together in a process called Polymerisation to form new compounds called Polymers. They are composed of organic condensation or addition polymers and may contain other substances to improve performance or economics. The vast majority of plastics are composed of polymers of carbon and hydrogen alone or with oxygen, nitrogen, chlorine or sulfur.

STONE AND CERAMIC MATERIALS

STONE: marble, granite, slate.
STONE BINDERS: plaster, cement, mortar, concrete.
CERAMICS: Baked clay, earthenware, heat resistant material, stoneware, porcelain.
GLASS
            - Shaping techniques: mould blowing, float glass making and lamination

FABRIC MATERIALS

Fabric materials can be natural or synthetic:

Natural:
- Vegetable origin: cotton, linen, hemp.
- Animal origin: wool, silk.
- Mineral origin: asbestos, metals.

Synthetic:
Nylon, polyester, rayon.