WORKSHOP TECHNOLOGY

1. Carpentry Shop

2. Carpentry Shop
Carpentry deals with the construction of wood
work such as roofs, floor, doors, windows,
trusses, workbenches, house hold furniture and
many other useful articles by means of suitable
wood.
The term joinery is used for connecting the
wooden parts with the different joints for
making doors, stairs, furniture and many other
articles.
The timber is the material used for carpentry and
joinery work.

3. Timber
Wood obtained from exogenous tree by cutting these
trees after their full growth and made suitable for
engineering or building purposes by sawing and
converting into various suitable commercial sizes.

4. Advantages of Timber
1. It is very easy to be worked with tools to give it
desired shape and size.
2. Structural connections and joints can be easily
made .
3. It is lighter in weight.
4. In framed structure, it suites equally well both
load bearing and non load bearing members.
5. In timber work, cost of material as well as
construction both are minimized as compared to
the other materials of similar use.
6. It responds very well to polishing

5. Advantages of Timber
7. It suites very favorably to doors, windows,
cabinet work furniture an decorative designs
and fittings.
8. It is quite suitable for making sound proof
construction.
9. It, being non conductor of heat, is favored for the
construction of houses. Such houses will remain
warm in winter and cool in summer.
10. It provides combination of strength, durability,
lightness and economy as compared to other
materials of construction.

6. Disadvantages of Timber
 Combustible
 Destroyed and decay due to attack of insects, fungi etc.
 Timber swell and undergoes shrinkage with changing
atmosphere humidity.
Uses of Timber
Post, beam, door – windows, roof member, Truss, paneling,
ceiling, partition wall, frame work, scaffolding, transmission
poles, wagon and coaches, bridges, boat, ships, agricultural
implants, sports goods, musical instruments etc.

7. Classification of Trees
1. Exogenous Tree or Outer growing
(a) Conifer or Evergreen Tree (Soft Wood)
(b) Deciduous ( Hard Wood)
2. Endogenous Tree or Inwards Growing
Exogenous trees grow in width by forming a new
layer of wood under the bark.
Endogenous trees grow by forming new fibers
within the trunk interspersed with the old fibers.

9. Structure of Timber Tree
1. Pith
2. Heart Wood
3. Sap Wood
4. Cambium Layer
5. Inner Bark or Bast
6. Outer Bark or Cortex
7. Annual Rings
8. Medullary Rays

10. Characteristics of Soft Wood and
Hard Wood
Soft Wood
1. It is resinous wood
having a fragrant smell
and regular texture.
2. Straight fiber and good
texture.
3. Light in colour and
weight.
4. Annual rings are
distinct
5. Good tensile strength and
week shear strength
Hard Wood
1. It is non-resinous wood
containing a fairly good
amount of acid.
2. Fibers are quite close and
compact.
3. Dark in colour and heavy
in weight.
4. Annual rings are not
distinct
5. Good tensile as well as
shear strength.

11. Soft Wood Hard Wood
6.Get split quickly
7.Weaker and less
durable
8.Catch fire soon
cannot withstand high
temperature.
9.It is easy to be
worked.
6. Does not split
quickly
7. stronger and more
durable
8. It has an added
advantage in its
refractoriness.
9. It is difficult to be
worked.

12. Softwood
•Cedar
•Linden/Lime/Basswood
•Pine
•Spruce
•Kail Wood
Hardwood
•Ash
•Aspen
•Birch
•Cherry
•Elm
•Hazel
•Mahogany
•Maple
•Oak
•Teak
•Walnut

13. Qualities of Good Timber
1. It Should have Straight Fiber
2. Wood obtained from near the pith is always better than the rest of the tree.
3. It should be free from knots.
4. It should not posses natural defects.
5. On sawing it should give a sweet smell.
6. It should have regular annual rings.
7. It should not clot the saw teeth during sawing.
8. It should be strong and heavy.
9. It should not split when nails are driven in to it.
10. It should bear high resistance to shock and stress.
11. It should have dark colour, give clear sound, easily workable, high
resistance to fire and free from decay.
12. On planning it should give silky texture and bright appearance.
13. It should not wrap or twist after seasoning.
14. It should respond well to polishing and painting.

14. Seasoning of Timber
Seasoning of timber is the process of drying or
removing the moisture or Sap presents in a
freshly felled timber, under more or less controlled
conditions.
Freshly felled timber contains a large humidity
or moisture roughly from 100 to 200%, based
upon dry weight of wood. If the timber is used
without seasoning it is liable to shrink , wrap
and crack.

15. Advantages of Seasoning
 Wood becomes hard, more durable, resistance to
shock and stresses produced.
 Its workability is improved.
 Its density is reduced, does not wrap after
seasoning.
 Shrinkage does not occur after seasoning.
 Defects like twisting, bowing and splitting do not
occur.
 Improved ability to polishing and painting.
 Its resistance to fire is increased.

16. Methods of Seasoning
1. Natural Seasoning
(a) Air Drying/ seasoning
(b) Water Seasoning
2. Artificial Seasoning
(a) Kiln Seasoning
(b) Chemical Seasoning
(c) Electrical Seasoning

17. Natural Seasoning
(a) Air Seasoning:-
In this method of seasoning the sawn
timber is stacked in a dry place about 30
cm above floor level with longitudinal and
crosspieces arranged one upon another,
leaving a space of a few Centimetersfor
free circulation of air. Wood
carpenter’s work after 2 years
fit for
and for
painter’s work after 4 years.

19. Advantages
(i)
(ii)
(iii)
It does not necessitate much attention
It is simple and cheap method.
Less chances of damage to the timber.
Disadvantages
(i) Very slow extends over years.
(ii) For large stacks considerable space is
required.
(iii)
(iv)
(v)
Rigid control cannot be exercised
Blocks the capital for a long time.
Timber may get damaged by insects and fungi
during seasoning period.

20. (b) Water Seasoning
This method of seasoning timber consists in
keeping logs of wood completely immersed
in a running stream of water, the longer
ends of the log being kept pointing up-
stream. By this process, the sap, sugar and
gum etc are leached out of the wood and
replaced by water. The logs are then taken
out and left to dry in an open places.

21. Advantages
It is quick process, tendency of wood to shrink
or wrap is reduced, less liable to be eaten away
by worm or to decay by dry rot.
Disadvantages
(i) The process reduces the elasticity and the
durability of the timber.
(ii) The timber becomes brittle.

22. 2. Artificial Seasoning
(a) Kiln Seasoning:-
• The timber is seasoned under controlled temperature and
humidity conditions with proper circulation and ventilation
system.
• The rise in temperature should be such that the timber
retains the original strength and elastic properties.
• The required humidity level is maintained to avoid warping
and cracking. The drying of timber at uniform rate is well
maintained by circulating hot air by fans and a certain
amount of steam is added in order to retain correct
humidity.
• The ventilation is provided to avoid over heating and
excessive humidity..

23. 2. Artificial Seasoning
(a) Kiln Seasoning:-
• The timber inside the chamber , on trolley is kept under
controlled conditions for about fortnight or depending upon
the initial water content and required moisture level.
• The quality of wood is inferior as compared to the one
seasoned by natural seasoned methods

24. Kiln Method

25. Advantages:-
1. moisture content can be reduced as per requirement.
2. less time required for seasoning, less shrinkage.
3. The drying is controlled, so no chances for the attack of
fungi and insects.
4. The drying of different surfaces is even and uniform.
Disadvantages:-
1. It is costly.
2. More skilled labor required.
3. Due to quick seasoning there are chances of
seasoning defects such as wrapping, internal cracks,
surface cracks etc. Regular checking is required.

26. ( C) Chemical Seasoning:-
It is also known as salt seasoning. In the method, the
timber is immersed in a solution of soluble salt. It is then
taken out and seasoned in ordinary way. The interior
surface of timber dries in advance of exterior one and
chances of formation of external cracks are reduced.
( D) Electrical Seasoning:-
• This method of seasoning works on the principle that heat is
produced when poor conductor are placed in the field of high
frequency.
• The wooden planks are made to pass through an induction coil
producing high frequency. Due to an induction effect moisture
contents in the wood is dried quickly. This method of drying is
employed in plywood manufacturing process.
• This method is not popular because of prohibitive cost, less
control on moisture content, sudden drying may damage wooden
fibers.

27. Electrical Seasoning

28. Wood Working Hand Tools
Classification of tools according to their
use is given below:-
1. Measuring and Marking Tools
2. Holding and Supporting Tools
3. Cutting Tools
4. Planning Tools
5. Boring and Drilling Tools
6. Striking Tools
7. Miscellaneous Tools

29. Measuring and Marking Tools: used for
measuring, marking, setting out angles and parallel lines and
testing
Measuring Tools
Folding Rule
Measuring Tapes
Try square
Bevel square
Marking Tools
Marking Knife or Scriber
Marking Gauge
Mortise Gauge

30. Measuring Tool:
(a) Folding Rule
(b) Measuring Steel Tape

31. Try Square: -
used for measuring and setting out dimensions, testing the
finish of a planed surfaces,
draw parallel lines at right angles (900 ) to plane surfaces,
draw mutually perpendicular lines over a plane surface and test
the squareness to two adjacent surfaces.
Bevel Sqaure :- measure 0 to 180 degree angle

32. Marking tool:-
Marking Knife or Scriber:
• It has sharp conical edges used to mark on even
hard surfaces.
• The front edge is hardened so as to resist wear and
tear. It is made up of carbon steel.
• It is used for measuring and marking the points and
lines on wooden stock before processing.

33. • Marking Gauge
It is used to draw parallel lines.
The movable portion of the gauge is adjustable to
suitable position and is tightened on the stem.
The piece which slides is called stock and scribing pin is
fixed on the stem.

34. Mortise gauge:
It is used to draw two parallel lines.
Its working is similar to marking gauge except it has
two sharp edges.
One fixed and second adjustable or fixed.

35. Holding and Supporting Tools
1. Carpenter’s bench and bench Hook
2. Carpenter’s Vice
3. Bar or T- Clamp and C-Clamp
4. Hand Screw

36. Carpenter’s bench and bench Hook:- It is a
table of rigid construction made of hard wood about 180cm x 120cm x
90cm (H) size. Four carpenter vice are fitted on opposite sides of
bench to hold the jobs during operation.

37. Carpenter’s Vice: it is mostly used for holding and supporting
wooden piece. Its one jaw is fixed to the side of the table while the other
is kept movable means of screw and handle.

38. Clamps and screws: These are used by carpenters for
holding and supporting wood pieces in position for carrying
out different operations.

39. Cutting Tools
Cutting tools may classified as follows:-
1. Saws
2. Chisels
3. Axe

40. Saws:-Sawing means cutting woods along the grains. The main
parts of a saw are blade and handle. The size of a saw is the
length of the blade in mm. the tooth is specified by its pitch and the
angle. The teeth are bent slightly by its pitch and the angle.
Common type of Saws :-
1. Rip saw
2. Cross-cut saw
3. Panel saw
4. Tenon saw (or back saw)
5. Dovetail saw
6. Compass or turning saw
7. Keyhole saw

41. Rip saw
Cross-cut saw
Tenon saw

42. Dovetail saw
Keyhole saw

43. Chisels:- In the wood work a large number of chisels
are used for cutting the wood in different manners to
produce desired shapes and verities.
(i) Firmer chisel
(ii) Bevelled edge firmer chisel
(iii) Parting chisel
(iv) Mortise Chisel
(v) Socket chisel
(vi) Gauge chisel

44. (i) Firmer chisel
(ii) Bevelled edge firmer
chisel
(iii) Parting chisel

45. (i) Mortise Chisel
(ii) Socket chisel
(iii) Gauge chisel

46. Axes:- is a cutting tool made of carbon steel. The
cutting edge is formed by beveling both sides of the
axe. It is employed for splitting wood along the grains
for rough work.
Axe
Axe
Side axe
adze
Side Axe
Adze

47. Planning Tools:- The planning tools are used for shaving or
smoothing plane surfaces. A plane may be described as a chisel
fastened to a metallic or wooden block called body.
The Chisel fastened to the body at an angle of 25 to 35 degree
respectively. Another Blade called Cap Iron is used for stiffening
the cutting blade, prevents chattering and helps in cutting and
curling of shavings. The Cap iron should be 1.5mm above the
cutting edge.
1. Wooden Jack Plane
2. Iron Jack Plane
3. Smoothing Plane

50. Boring and Drilling Tools:- for producing
holes in wood.

51. Auger
Gimlet
Bradwal
Brace

52. Hand Drill

53. Striking Tools
1. Mallet
2. Claw Hammer
3. Peen Hammer
Mallet
Claw
Hammer Peen Hammer

54. Miscellaneous Tools
1. Screw Driver
2. Pincer
3. Rasp file

55. Wood Working Processes
1. Marking and Laying out
2. Sawing
3. Planning
4. Mortising and Tenoning
5. Boring
6. Grooving
7. Moulding
8. Recessing

56. Carpentry Joints
1. Halving
(a) Corner Lap joint
(b) T- lap Joint
(c) Dove-Tail Joint
(d) Cross-Lap Joint
2. Mitre Joint
3. Mortise and Tenon Joint
4. Briddle Joint
5. Grooving and Tongueing
6. Dove- Tail Joint
7. Dovel Joint

57. Half laps (T-lap Joint)
Left to right: Half lap, mitred half lap, cross lap and dovetail
lap
Half lap joints are used extensively in traditional timberframing,
construction and cabinetry for framing. They are quick and easy
to make and provide reasonable strength through good long
grain to long grain gluing surface. The shoulders provide some
resistance to racking (diagonal distortion). They may be
reinforced with dowels or mechanical fasteners to resist
twisting.
Applications
Frame assembly in cabinet making
Temporary framing
Some applications in timber frame construction table

58. Half laps (T-lap
Joint)
Cross Lap Joint
End Lap Joint

59. End lap
Also known simply as a 'pull lap', it is the basic form of the
lap joint and is used when joining members end to end
either parallel or at right angles. When the joint forms a
corner, as in a rectangular frame, the joint is often called a
corner lap. This is the most common form of end lap and
is used most in framing.
For a half lap in which the members are parallel, the
joint may be known as a half lap splice. This is
a splice joint and is an alternative to scarfing when
joining shorter members end to end.
Both members in an end lap have one shoulder and one
cheek each.
Used for:
Internal cabinet frames
Visible frames when the frame members are to be
shaped.

60. Cross lap
The main difference between this and the basic half lap is
that the joint occurs in the middle of one or both members,
rather than at the end. The two members are at right angles
to each other and one member may terminate at the joint,
or it may carry on beyond it. When one of the members
terminates at the shin , it is often referred to as a Tee lap or
middle lap. In a cross lap where both members continue
beyond the joint, each member has two shoulders and one
cheek. For a Tee lap, one of the members has only one
shoulder.
Used for:
Internal cabinet frames
Simple framing and bracing

61. Dovetail
This is a lap in which the housing has been cut at an
angle which resists withdrawal of the stem from the
cross-piece.
Used for framing applications where tension forces
could pull the joint apart

62. Dove Tail Joint

63. Mitre half lap
This is a variation of the end lap which shows a
mitre on the face of the finished work.
The mitred half lap is the weakest version of the
joint because of the reduced gluing surface.
Use for visible framing applications where a mitre
corner is desired

64. Mortise and Tenon joint
The mortise and tenon joint has been used for thousands
of years by woodworkers around the world to join pieces
of wood, mainly when the adjoining pieces connect at an
angle of 90°. In its basic form it is both simple and strong.
Although there are many joint variations, the basic mortise
and tenon comprises two components: the mortise hole and
the tenon. The tenon, formed on the end of a member
generally referred to as a rail, is inserted into a square or
rectangular hole cut into the corresponding member. The
tenon is cut to fit the mortise hole exactly and usually has
shoulders that seat when the joint fully enters the mortise
hole. The joint may be glued, pinned, or wedged to lock it
in place.

66. Briddle Joint
Dovel
Joint
Grooving and
Tongueing

67. Safety Precautions
•Before starting any wood working machine in carpentry shop, it should
be ensured that all the safety guards are in proper places and secured
well.
•While working on a circular saw, one should not stand in a line with the
plane of the rotating blade and always keep your fingers away from the
reach of blade.
•While working on wood lathe machine, the job should be properly held.
•The wooden pieces should not be fed to the sewing machines faster than
the cutting speed of the machine.
•One should not use defective or damaged carpentry tools and machines
while carrying out work in carpentry shop.
•No carpentry tools should be thrown for saving time in handling.
•Nails, screws should be properly kept in a box for proper house keeping.
•Sufficient safety precautions need to be taken for preventing fire
accidents in the carpentry shop