2. ▣ WOOD
▣ TIMBER
▣ DIFFERENCE BETWEEN WOOD
AND TIMBER
▣ TIMBER IN DETAIL
▣ INDUSTRIAL TIMBER
▣ FORMS OF TIMBER
▣ DEFECTS ON TIMBER
▣ PRESERVATIVE METHODS OF
TIMBER
▣ INTRODUCTIONS OF VARIOUS
TYPES OF WOOD AND
TIMBER AND THEIR USES
3. ▣ Wood is a hand fibrous material that forms the main substances of the
trunk or branches of a tree. It is cut and used on timber or for fuel
purpose. It is solid material derived from woody plants , not only
trees but also shrubs. It is a heterogeneous, hygroscope and cellular
material.
▣ Oak, Maple, Mahogany, Cherry, Walnut, Rosewood, Teak, etc. are
known as HARDWOOD. Pine, Ash, Hickory, Beech, Birch, Cedar,
Fir, Spruce.etc. are ex. Of SOFTWOOD.
4. ▣ It is a wood material which is manufactured into boards. It is used for building,
carpentry and various construction or structural purposes. It can be rough or
finished.
▣ As a rough, it is the raw material for furniture making and other items
required additional cutting and shaping. As a finished it is available in drill
sizes or construction industry and for high grade flooring.
▣ Timber plant species are found in 150 species which are produced
in INDIA.
▣ Tea, Sal, Sandalwood, Sea sum Babul, Banyan, Coconut, Deodar etc, are
some ex. Of Timber.
▣ Timber is available in different forms.–
1. Converted timber , which is sawn and cut into suitable
commercial sizes.
2. Rough timber which is obtained after falling a tree.
3. Standing timber which is available in a living tree.
5. ▣ Wood includes all types of wood which may be burning wood , structural
wood, furniture wood etc. but when wood suitable for use as a structural
material is called Timber.
▣ Wood is commonly found in the stems and roots of the trees. It is natural
composite of cello use fibers.
▣ Timber is used to refer to any stage of the wood after the tree has been cut
down. This may include the felled tree, wood processed for construction ,
wood pulp for paper production etc. Timber is also known as LUMBER.
6. ▣ PROPERTIES OF TIMBER
▣ Timber with heavy weight is considered best quality.
▣ It should be hard uniform and compact.
▣ It should have dark color, straight fibers, and shinning appearance and should
be free from defects and good sound should emit when struck.
▣ SEASONING OF TIMBER
▣ This is the process of drying of timber in order to remove all the
plant juice and moisture out of it so that it will not decay.
Seasoning of timber may be done naturally or artificially.
▣ PRESERVATION OF TIMBER
▣ It is the process which protect the timber from moisture, fungi, insects and
direct weathering effects to ensure its increased life. Oil paints, coal tar,
chemical salts etc are some preservatives are used.
7.
8. ▣ Timber which is scientifically prepared in factory to get the desired shape,
size, appearance, and strength is known as INDUSTRIAL TIMBER. It is
available in various variety such as Plywood, Veneer, Laminated timber,
block board, fiber boards etc.
▣ Veneers are thin sheets or slices of wood of superior quality which are
knife cut by various processes. It is used to produce plywood, batten
boards and laminated boards and this process is called veneering.
Thickness – varies from 4mm to as much as 6mm or
even more.
▣ Plywood is prepared by cementing together thin boards or sheets or wood
into panels. Three or more veneers which are always odd in numbers are
placed one above the other so that the grain of each layer is at right angles
to the grain in the adjacent layer. It is used for interior partition , doors and
paneling. It is generally manufactured in 3 ply, 5 ply , 7 ply and so on.
Thickness - varies from 3mm to 5mm.
9. ▣ Fiber board is rigid board which is prepared after processing pieces of wood,
cane and then pressing them together that’s why it ia also called pressed wood
or reconstructed wood.. It is available in various forms like laminated boards,
hard boards etc. It is used for wall paneling, suspending ceiling and partitions,
table tops, for flush doors etc. thickness- varies from 6mm to as much as
25mm.
▣ Block board has a core made up of strips of wood glued or joined to form a
slab which is further glued between two or more outer veneers in such a way that
direction of the grain of the core blocks running at right angles to the adjacent
outer veneers. These are of two types: commercial and decorative. It
is used for furniture, paneling, partition.
Thickness are 12mm to 50mm length vary from 1.2mm to2.4mm and
width from 90cm to 1.2m.
10. ▣ Hard board are manufactured from wood wastes obtained from saw mills,
inferior timber or short logs. Raw material is converted into chips with the
help of machines which are softened with steam and converted into fibers.
The maximum length is 4.75m and thickness varies from 2mm to 20mm. It
is used for interior or exterior wall panels, ceiling, siding, table and counter
tops etc. It is free from defects like shakes and knots.
▣ Batten boards are just like laminate boards and block boards are made
from timber blocks of width of 8cm and 2to 3cm thick. Direction of the
grains of core batten is at right angles to that of adjacent out ply sheet. There
are used for door panels, table top and other large surfaces.
11. ▣ BATTENS are small sectioned timber pieces.
▣ LOGS : Trunks of trees left after removing all the branches
is called log.
▣ BAULK is roughly squared swan log.
▣ PLANKS are timber pieces having parallel sides with less than 5cm thickness
and width always more than 5cm.
▣ BOARD is also timber piece with parallel sides with less
than 5cm thickness and more than 15cm width.
▣ DEAL is also parallel sided piece , thickness varies from 5cm to10cm and
width should not exceed 23cm.
▣ SCANTLINGS are timber pieces , thickness and breath is always more than
5cm and length is not less than 20cm.
▣ POLE OR SPAR is a log having 20cm diameter.
12. ▣ A good timber should be hard ,tough, durable, heavy, straight and
compact fibers, properly seasoned, elastic, dark and uniform color, sweet
smell and freshly surface and adquate fire resistance.
▣ It should be capable of resisting the action of fungi, chemicals and physical
agencies and free from knots, twists, upsets, burls, shakes etc.
▣ A clear ringing sound should be emitted by the timber when struck.
13.
14. ▣ SHAKES : Cracks which partly or completely separate the fibers of wood. Shakes are
many types- star shakes, heart shakes, cup shakes, ring shakes, radial shakes.
▣ RIND GALLS : Curved swelling on the body of the tree.
▣ TWISTED FIBRES: Twisting of young trees constantly in one direction under the
action of strong prevalent winds.
▣ UPSETS OR RUPTURES : This defect changes in direction of wooden fibers due to
felling of tree or fast blowing wind.
▣ KNOTS: These are found at the bases of branches cut off from the tree. They may be
dead, live loose or tight. It is very difficult to plane timber at knots.
▣ WIND CRACKS: Cracks on the outer surface of the tree due to atmospheric
agencies.
▣ BURLS: Irregular projections appears on the surface of the tree
▣ CALLUS: Soft tissue or skin which covers the wounds of the tree is called callus.
▣ COARSE GRAIN: Timber having widened annual rings.
▣ DEAD WOOD : It is indicated by its reddish color and light weight.
▣ DRUXINESS: White decayed spots of timber remain concealed under healthy
wood due ti access of fungi.
▣ FOXINESS: This defect is indicating by red or yellow tinge in wood.
15. ▣ BOW : Bow means when planks of converted timber shrink and
bend in curved form in the direction of length.
▣ CUP : When wooden planks bend in curved form in transverse
direction.
▣ TWIST: Distorted spirally wooden plank along its length.
▣ CASE HARDENING: Upper surface of timber dries very fast and
shrinks.
▣ HONEY COMBING DEFECTS: Various radial as well as circular
cracks develop in internal portion of the timber due to stresses
developed during drying.
▣ RADIAL SHAKES: Radial cracks on the surface of timber
▣ CHECK: A crack separating wood fibers.
▣ SPLIT: When check extends from one end to other.
▣ WANE: Original or natural rounded surface on timber.
▣ DIAGNOL GRAINS: When timber is improperly sawn then
diagonal marks develops on straight grained surface of timber.
16.
17. ▣ Coal tar, Oil paints , certain chemicals and Ascu treatments are generally
used to protect timber.
▣ CHARRING : The timber is charred to be firstly kept wet one hours and then
burnt to a depth of about 15mm and cooled with water, It is called charring. This
protects timber from moisture, fungi, or white aunts.
▣ TARRING: In this method a later of hot tar is applied on the
surface of timber.
▣ Paint : it is applied to timber not only makes it beautiful look but also acts as a
preservative.
▣ WOLMAN’S SALTS : It is a Mixture of creosote oil and sodium fluoride.
It protects timber from fungi.
▣ ASCU TREATMENT: It is prepared by mixing six parts of Hydrated
arsenic pent oxide, Copper sulphate and Potassium Dichromate with 100
parts of water. It gives protection from white aunts.
18. ▣ VACCUM PRESSURE PROCESS: It is considered one of
the best method which is two types
1. Bethel or full cell process– In this process air and moisture get removed
from the timber cells.
2. Rue ping or Empty cell process
▣ HOT AND COLD PROCESS: In this process timber is stacked in the
tank and cold preservative solution till timber stacks get completely
submerged , then heated to a temperature of about 90 degree C and
maintained this temperature for some times.
▣ SEASONING OF TIMBER : Proper damp proofing and providing free
circulation of air around the built in portion of timber are essential for
preservation of timber used . If timber is not properly seasoned then no
preservatives protect th timber.
19. ▣ OAK , a heavy strong
colored hard wood is used to
craft American and English
country designs and mostly
used for sports good Its color is
yellowish brown and possesses
straight silvery grains.
Its weights 865kg and very
strong and durable.
20. ▣ MAPLE is so hard and resistant to
smocks that is often used for bowling
alley floors. The bird eye figure in
maple is said to be the result of stunted
growth and is quite rare.
▣ It is used for American colonial
furniture, especially in
medium and lower priced categories. It
can also be stained to simulate cherry
wood which it resembles.
21. ▣ MAHOGANY is also known as
Honduras mahogany and much ten
valuable wood. Being ten strong ,
not as durable not as beautiful
when finished
▣ It has reddish brown color and
may display stripe ribbon ,
broken stripe, rope ripple, mottle,
fiddle back or bristle figure.
▣ It is used extensively in the
crafting of Georgian empire and
furniture , pattern making cabinet
work etc.
▣ It contains resinous oil to save
itself from insects attack.
▣ Weights 720kg after seasoning.
22. ▣ CHERRY is sometimes
called ‘ fruitwood’ and is grown
in the eastern half of U.S.A. It
has been called New England
Mahogany and is often used to
craft 18th century colonial and
French provincial designs.
▣ A moderately hard, strong,
closed grain, light to red brown
wood, cherry resists wrapping
and checking. It is easy to card
and polish and is used in
variety of styles.
23. ▣ WALNUT is one of the most
versatile and popular cabinet
making wood. It grows in
Europe, America and Asia. It is
strong , hard and durable
without being excessively
heavy. It has excellent word
working qualities and takes
finishes well. It is light to dark ,
chocolate brown in color with a
straight grain in the trunk.
▣ It is used in all types of fine
cabinet work especially 18th
century reproductions.
24. ▣ ROSEWOOD is a
dark reddish brown color
hardwood
,fragrant and has closed
grains. It is not easy to work
and takes high polish.
▣ It is used in musical
instrument, piano cases, tool
handles, art projects, veneers
and furniture.
25. ▣ TEAK is yellow to dark brown
hardwood which is extremely
heavy, strong and durable. Its
fibers are straight , fir resistant,
acidic action resistant and white
ant resistant,.
▣ It can be used for any structural
or decorative work, such as ship
building, railway sleepers,
railway carriages and furniture
etc.
▣ Its weights 770 kg.
26. ▣ BIRCH is hard, heavy close
grained hardwood with a light
brown or reddish colored
heartwood and cream or light
sapwood.
27. ▣ CEDAR is knotty softwood
which has been a red brown
color with light streaks. It
aromatic and moth repellent
qualities have made it a popular
wood for lining drawers, boxes,
simple cases and storage closets
are also constructed from this
light brittle wood.
28. ▣ REDWOOD is rare, valuable
and best quality of it comes
from the heartwood which is
resistant to deterioration due to
sunlight, moisture and insects.
▣ It is used to craft outdoor
furniture and decorative
curving. Its burls have ‘ a
cluster of eyes’ figure.
29. ▣ HEMLOCK is light in weight ,
uniformly texture has law
resistance to decay and non
resinous.
▣ It is used for construction
lumber, plants, door boards,
paneling, sub flooring and craft
works.
30. ▣ SPRUCE is strong ang light in
weight has low resistance to
decay, moderate shrinkage.
▣ It is used for marts and crates
spares for ships and aircrafts,
boxes, general millworks,
ladders etc.
31. ▣ FIR is easy to work and
finishes well, uniform in
texture and no resinous has
low resistance to decay.
▣ It is used in making
furniture, door and window
frames, veneer, and interior
trim.
32. ▣ PINE is a soft white or pale
yrllow wood which is light
weight , straight grain and lacks
figure. It decays easily when
comes in contact with soil. It is
used in the manufacturing of
matches.
▣ While other colored pines are
quite hard and tough.It is used
for pattern making, frames for
doors and windows, paving
materials etc.
▣ There are more than 100
species of pine.
33. ▣ ASH is a heavy ring porous
wood has a prominent grains
that resembles oak and white
to light brown color. It burls
have a twisted interwoven
figure.
▣ It is widely used for
structural frames and steam
bent furniture pieces.
34. ▣ HICKORY is one of the hardest
and heaviest softwood. Pecan is
a species of hickory some times
used in furniture.
▣ It has close grains without much
figures. It is used for structural
parts. Decorative hickory
veneers are also commonly used.
35. ▣ BEECH has tiny pores and large
conspicuous medullar rays and
similar in appearance to maple,
reddish brown heartwood , light
sapwood and relatively
inexpensive.
▣ It is often used for frames, a
variety of bent and turned parts
quarter sliced and half round cut
beech veneers are commonly
used.
36. It is strong, hard, tough, durable,
quite strong and difficult to
work. Its color is whitish red
which is turns brown due to
exposure and not available in
large length. Weight is 880kg.
▣ It is used for making the wheels
of bullock cart, tool handles,
agricultural instruments and well
curbs.
37. ▣ CHIR is straight long timber and
have conical leaves. Its color is
yellow becomes more and more
dark due to exposure. Weight is
560kg and easy to work.
▣ It is used for railway sleepers,
piles, railway carriages, cheap
furniture etc.
38. ▣ BAKUL IS REDDISH
BROWN IN COLOR
AND USED MOSTLY
FOR MAKING
CABINETS. WEIGHT
IS 880KG.
39. ▣BANYAN is a species whose
aerial roots are utilized for
tent polls, well curbs etc.
▣ It is strong and durable
only under water . Its
color is
brown and weight 580kg.
40. ▣ BAMBOO IS USED FOR A
SCAFFOLDING, THATCH
ROOFS AND
TEMPORARY BRIDGES.
41. ▣ COCONUT IS USED AS
POLES, PILES, FURNITURE
AND FRAME WORK IN
CONCRETE
CONSTRUCTION.
42. ▣ SAL is a very good variety of
timber and can be used for any
purpose but not easy to work.
Its color is light brown or
yellow .
▣ It is used for tent pegs, doors
and window frames and as
wooden piles, bullies etc, but
can not used for decorative
works.
43. ▣ SHISHAM is also called Tali or
Sissue , one of the most useful
and high class timber , heayy
and can be seasoned easily, Its
color is dark brown containing
golden and dark brown colored
linings.
▣ It is used for furniture's,
plywood, sports goods , railway
sleepers, bridges piles etc.
44. ▣ ARJUN is very strong
, heavy and durable timber .
Its color is dark brown.
▣ It is used in the form of posts,
beams , rafters etc.
45. ▣ LAUREL is a hard tough type
of timber and likely to crack
and resist attack of dry rot. Its
color is dark brown.
▣ It is used for house
construction , boat
construction, structural work
and railway sleepers.
46. ▣ MANGO is moderately
strong , easy to work and in
deep grey color.
▣ It is used for making cheap
furniture, packing boxes, panels
for doors and windows etc.
47. ▣ TAMARIND is a fruit
giving tree, very knotty
and durable timber and color is
dark brown.
▣ It is used for well curbs,
sugar mills, carts, brick
burning. Agricultural
implements.
