WOOD
• WOOD IS MADE UP OF FIBERS AND CELLULOSE.
• ANGIOSPERMS AND GYMNOSPERMS.
• GYMNOSPERMS – CONIFEROUS,EVERGREENS
CONE BEARING,
NEEDLELIKE LEAVES
SOFT WOOD
HIGHEST TREES;85-110 MTS
PINE,CYPRESS,FIR,SPRUCE
650 SPECIES
Spruce
fir
fir
pine tree
ANGIOSPERMS
• LEAFY TREES AND LEAVES ARE WIDER
• HEAVIER THAN GYMNOSPERMS
• KNOWN AS HARD WOODS
• 1,500 VARIETY OF TREES THAT ARE FOR
COMMERCIAL USE.
Different types of wood
teak
Honduras
Mahogany
Spanish
cedar
Ash
Aromatic
cedar
Walnut
Cherry
Birch
Maple
Red Oak
MAHOGANY
HICKORY WOOD
DEFECTS
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TWISTED FIBER
ONDULATED WOOD
CURVATURES IN THE TRUNK
CRACKS OR FISSURES
SPLITS
DEAD LAYERS BETWEEN RINGS OF ALIVE WOOD
Wood diseases
DISEASES OCCUR WHEN:
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CUTS
FUNGI
MISTLE-TOE ; A PARASITIC PLANT
LARVAE
ENVIRONMENTAL FACTORS
• Like all living things, trees are susceptible to disease. A
tree needs a good supply of light, water, carbon dioxide
and nutrients from the environment for optimum growth.
A lack of one or more of these may lead to reduced
growth and put the tree under stress. If a tree is
stressed then it may not have the energy required to
manufacture important defenses and can become
vulnerable to disease.
• If a diseased tree eventually dies it can sometimes be
difficult to diagnose the original cause because problems
are often complex and cumulative. For example, a tree
could be weakened by drought and then become the
victim of a fungal attack; environmental factors such as
temperature, storm wounds or pollution may play a part;
or sometimes more than one disease may be present.
• Tree disease can stem from fungal, bacterial or viral
sources.
WOOD DISEASES
OAK DECLINE
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Oak decline is a syndrome in which bacteria, along with insect infestation or
weather damage, interact to bring about a serious decline in tree condition.
There are two kinds of decline: acute and chronic.
Acute oak decline affects mature oaks and bacteria causes stem bleeding
where dark, sticky fluid oozes from cracks in the tree trunk.
Chronic oak decline may take many years to kill a tree. Symptoms include
deterioration of the foliage; leaves may be smaller than normal, pale or
yellowish. In some cases the foliage may be thinly spread over the entire
crown and death of twigs and branches follow.
Amillaria Root Rot
• The disease attacks hardwoods and softwoods and kills
shrubs, vines, and forbs It commercially destructive, a
major cause of oak decline. The Armillaria can kill trees that
are already weakened by competition, other pests, or
climatic factors. It can also infect healthy trees, either
killing them outright or predisposing them to attacks by
other fungi or insects.
Powdery mildew is a
common disease that appears
as a white powdery substance
on the leaf surface. The
powdery appearance comes
from millions of tiny fungal
spores, which are spread in air
currents to cause new
infections. It attacks all kinds
of trees.
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Sudden oak death
• It is caused by a fungus PHYTOPHORA and has killed
thousands of oaks in North America and Europe.It
causes a bleeding canker on the stem
• Heart rot is a fungal disease that causes the decay of
wood at the center of the trunk and branches. Fungi
enter the tree through wounds in the bark and decay
the heartwood. The diseased heartwood softens
resulting in trees being structurally weaker and prone to
breakage. Heart rot is all throughout the world affecting
all hardwood trees and can be very difficult to prevent.
An indication of heart rot is the presence of mushroom or
fungus on the tree.
• FROST CRACKS
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• Frost cracks are due to quick changes in winter
temperatures
• They are vertical cracks in the stems of trees. On sunny days
in the winter, bark will warm up, causing cells to expand in the
bark and wood directly below the bark. As the sun sets,
temperatures drop quickly, causing the bark to cool and
contract. The wood under the bark does not cool as quickly,
causing the bark to split. Once damaged, the injured area
can split back open on very cold, winter days.
Olive tree tuberculosis is a disease found on Olive trees
in Spain that is caused by the bacteria Pseudomonas
syringae. When this bacteria is introduced into a wound on
the tree caused by hail, pruning or by the beating of the
branches to harvest the Olives it results in the formation of
a like formation that starts off round and light brown and
then grows into an irregular wart shaped canker that ends
up with a dark brown color and very hard.
WOOD DISEASES INVESTIGATION
• Make an investigation about wood diseases (8)
• Add information and pictures of each.
• Send it a week from today or hand it printed.
• Individual- Can’t have 2 exact investigations.
• 16 pts.
Wood decay
• Wood decay begins with any injury that breaks
through the bark and exposes the wood. The injury
may be the result of a weed whip, animal damage,
broken branch, etc. The damaged cells undergo
chemical changes and become discolored. Many
microorganisms land on the surface of the wound.
Some of these organisms, commonly referred to as
pioneer colonizers, begin to grow and colonize the
wounded tissue.
Fungal decay: Brown rot
White rot
Bacterial ,fungi, viral infections: Stem bleeding
fungi
FUNGI
HUMIDITY- SAP
Sap is the juice that feeds plants with all
dissolved substances and circulates in the vessels.
When wood is cut there is humidity in its vessels
so it must dry to be used.
If NOT dried in a proper way and then used in
any type of work ,it will suffer distortion later
on.
NATURAL DRYING
• Oldest and simplest way
• Takes longer time and space
• Can be dried outdoors or indoors.
OUT DOOR DRYING
Depends on the weather condition.
Must be prepared during the rainy season since it’s
when wood has less sap because it concentrates
in the root.
Should not be left on floor because of fermentation
and humidity. A piling system must be used where
air can circulate among the pieces drying them.
NATURAL ACCELERATED DRYING
• PLACING WOOD IN WATER TO DRY SAP AND
ELIMINATION OF SALTS.
• IN SOME PLACES IT IS PLACED IN RIVERS AND AT THE
SAME TIME IT IS TRANSPORTED TO ANOTHER PLACE.
• SOMETIMES WOOD DARKENS SLIGHTLY.
INDOOR DRYING
TWO MONTHS AFTER BEING CUT WOOD IS PLACED INDOOR
WITH PLENTY OF VENTILATION.
DIFFERENT TYPES OF GLUE
• When two pieces are united with nails,screws ,joints
sometimes they also need glue.There are hot,cold
and with casein.
GLUTIN GLUE:made from residious materials of
animals;pieces of skin,bones,cartiledges.They are
heated at high temperatures and are resistent.
SYNTHETIC RESIN GLUE: they are bought already
prepared. More resistent than others .Resistent to
humidity,putrefaction and mold.
CASEIN GLUE: made from milk.Sold in powder,or solid,
very resistent and stand humidity.
CASEIN GLUE
Paint
components
Pigmen
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t: provides color (also can provide corrosion resistance,
water barrier properties, viscosity control.
They can be found throughout nature in clays, herbs, nuts,
berries, barks, carbon, charcoal, and soot. They are ground
down into powder and usually boiled several times in water to
remove impurities.
Binder (resin):Binds the ingredients (holds everything together),
Natural binders are chalk, lime, casein (non-fat milk curds),
animal or vegetable glues, and oil.
Lime has antibacterial qualities and is used for interior or exterior
walls
Casein is the binder for milk paints; it is used for interior walls and
for fine arts.
Animal and vegetable glues make chalky paint and are usually
used in fine arts.
Oil is used for woodwork paint and fine art. It "binds" the pigment
together, and provides film integrity and adhesion.
Paint Components
Binder (resin):Binds the ingredients (holds everything together),
Natural binders are chalk, lime, casein (non-fat milk curds),
animal or vegetable glues, and oil.
Lime has antibacterial qualities and is used for interior or exterior
walls
Casein is the binder for milk paints; it is used for interior walls and
for fine arts.
Animal and vegetable glues make chalky paint and are usually
used in fine arts.
Oil is used for woodwork paint and fine art. It "binds" the pigment
together, and provides film integrity and adhesion.
• CARRIER/VEHICLE/SOLVENT/LIQUID
It provides desired consistency and makes it possible to
apply the pigment and binder to the surface being
painted. The main purpose of the vehicle is to adjust the
viscosity of the paint.
• Water is the main vehicle for water based paints.
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• ADDITIVES
These are low-level ingredients that provide specific
paint properties such as mildew resistance, good flow
and levelling.
• Some examples include additives to improve pigment
stability, control foaming, control skinning, etc. Other
additives might be thickeners or biocides to fight
bacterial growth.
Paint components
PAINTS
• ACCORDING TO THE GLUTINOUS, PAINT CAN BE
DIVIDED INTO THE FOLLOWING GROUPS:
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QUICK LIME PAINT – CALCIUM OXIDE
GLUE PAINT
WATER PAINT
OIL PAINT
LACQUER : varnish made from sap of certain trees
4’s
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4 types of binders
4 things used for pigments
4 ways of artificial drying
4 components of paint
4 characteristics of angiosperms
4 characteristics of gymnosperms
4 types of paints
4 things additives do
SEALERS &VARNISHES
Every wood has pores; some have them big and
others small. So it must be smooth before finishing the
product.This is obtained by sanding the wood with
different types of sand paper,some are coarse while
others are fine. At the same time some stains or
scratches can be eliminated.
There are two types of sealers; resine and sillicone.
After sanding, the sealer must be applied .It must dry
up and then sanded again until no signs of sealer
show up. Add another coat of sealer and when it is
dried add varnish.
Varnish needs to be diluted,some in turpentine, others
in thinners.
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Varnishes are transparent with no pigment and are
diluted before using them.
Varnishes also known as lacquers add beauty and
protection to wood.
There are many different types of lacquers ; oil,
alcohol, nitrocellulose, plastic etc.
Some have sheen tones;not so glossy , from ultra
matte to high gloss.
Today varnishes can be found in sprays or in brush on
styles.
WAYS OF PAINTING
• CLOTH METHOD
• This is the oldest way of painting where a ball is
made with a piece of cloth-preferably T-shirt and it
is tied at the end.
• It is dipped in paint and applied in circular form
repeating the process when each layer is dried.
• BRUSH
• Nowadays this way is not very popular. Big areas
should be covered with big brushes while small
areas should be covered with small brushes.
GUN
The most popular method because it gives a very
nice finish to the piece . It is the fastest method.
Wood joinery
JOINERY- JOINTS
• Joinery often refers to the part of wood working
that involves the joining together of parts of wood.
• Traditional wood joinery techniques often work
without mechanical fasteners. There are different
types of joinery for different structures, for example
the joinery used to build a house is different from
that used to make certain toys .
Butt joint
A butt joint is when one piece of
wood butts into another (most often
at a right angle, or square to the
other board) and is fastened using
mechanical fasteners. This type of
joint is often used in wall framing
on construction sites
Mitered butt joint
• It is the same as a butt joint only that the 2 pieces of
wood are joined at an angle.
HALF LAPP JOINT
MORTISE AND TENON JOINT
one of the strongest joints.Mostly
used in tables and chairs.
BRACE MORTISE AND TENON
USED IN A DIAGONAL WAY TO HOLD
TWO OTHER PARTS.
DOVE TAIL
THROUGH DOVE TAIL JOINT
A beautiful and very strong joint.
Usually used in elegant furniture.
SLIDING DOVE TAIL
Lots of uses. Very common in
drawers.
RABBET JOINT
Usually used in cabinetry.
JOINT
EVALUATION
• Wood project
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30
Joinery homework
10
Cooking lab
10
Crossword
10
Wood diseases investigation 12