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Carpentry Shop This PPT Help Students to Understand the Basic Concept of Carpentry Shop, Carpentry Tools and Joints.

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  • 1. Carpentry Shop By : Mr. Sunil Kumar Ojha Assistant Professor Mechanical Engineering Department JRE Group of Institutions, Greater Noida

2. Carpentry Shop Carpentry deals with the construction of worksuch as making roofs, floors portions etc of a building , 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 such as 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 cuttingthese 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 togive 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 and 5. Advantages of Timber 7. It suites very favorably to doors, windows, cabinet work furniture an decorative designs and fittings. 8. It is quit suitable for making sound proof construction. 9. It, being non conductor of heat, is favoured 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 Diminish due to rusting Destroyed and decay due to attack of insects, fungi,terminators etc. Timber swell and undergoes shrinkage with changing atmosphere humidity.Uses of Timber Piles, 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 Exogenous Tree or Outer growing (a) Conifer or Evergreen Tree (Soft Wood) (b) Deciduous ( Hard Wood) 2. Endogenous Tree or Inwards Growing 1.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. 8. Structure of Timber Tree 1. 2. 3. 4. 5.6. 7. 8.Pith Heart Wood Sap Wood Cambium Layer Inner Bark or Bast Outer Bark or Cortex Annual Rings Medullary Rays 9. Characteristics of Soft Wood and Hard Wood Soft Wood 1. It is resinous woodhaving a fragrant smell and regular texture. 2. Straight fiber and good texture. 3. Light in colour and weight.Hard Wood 1.2. 3. 4. annual rings are4.distinct 5. Good tensile strength5.It is non-resinous wood containing a fairly good amount of acid. Fibers are quite close and compact. Dark in colour and heavy in weight. Annual rings are not distinct Good tensile as well as shear strength. 10. Soft WoodHard Wood6. 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 splitquickly 7. stronger and more durable 8. It has an added advantage in its refractoriness. 9. It is difficult to be worked. 11. SoftwoodCedar Linden/Lime/Basswood Pine Spruce Kail WoodHardwoodAsh Aspen Birch Cherry Elm Hazel Mahogany Maple Oak Teak Walnut 12. Defects in Timber (a)Natural DefectsExp: Knots, Shakes, Twisted Fibers, Rind Galls etc.(b) Defects Occurring During Conversion,Seasoning or Use Exp: Shakes, Distortion, case hardening, Honey Combing etc.(c) Defects Due to action of Fungi or Insects Exp: Dry rot, Wet rot 13. (CAUSED DUE TO)NATURAL FORCESINSEC TSFUNGI CONVERSI ONSEASONI NG 14. CHEMICAL STAINKNOTS SHAKESTWISTED FIBRES RIND GALLS UPSETSBURL S 15. CHEMICAL STAIN:-THE WOOD IS SOMETIMES DISCOLOURED BY THE CHEMICAL ACTION CAUSED WITH IT BY SOME EXTERNAL AGENCY.THIS IS KNOWN AS CHEMICAL STAIN.RIND GALLS:-THE RIND MEANS BARK AND GALL INDICATES ABNORMAL GROWTH.HENCE PECULIAR CURVED SWELLING FOUND ON THE BODY OF TREE ARE KNOWN AS RIND GALL.THEY DEVELOP AT POINTS FROM WHERE BRANCHES ARE IMPROPERLY CUT OFF OR REMOVED.THEY ARE RARELY FOUND IN A TREE AND THE 16. COARSE GRAIN:-IF THE TREE GROWS RAPIDLY,THE ANNUAL RINGS ARE WIDENED.IT IS KNOWN AS THE COARSED GRAIN TIMBER AND SUCH TIMBER POSSESSES LESS STRENGTH KNOTS:-THESE ARE THE BASES OF BRANCHES OR LIMBS WHICH ARE BROKEN OR CUT OFF FROM THE TREE.THE PORTION FROM WHICH THE BRANCH IS REMOVED RECIEVES NOURISHMENT FROM THE STEM FOR A PRETTY LONG TIME AND IT ULTIMATELY RESULTS IN FORMATION OF DARK HARD RINGS WHICH ARE KNOWN AS KNOTS.AS CONTINUITY OF WOOD FIBRES ARE BROKEN BY 17. SHAKES:-THESE ARE LONGITUDINAL SEPERATIONS IN WOOD BETWEEN THE ANNUAL RINGS.THESE ARE CRACKS WHICH PARTLY OR COMPLETELY SEPARATE FIBRES OF WOOD.THE SEPERATIONS MAKE THE WOOD UNDESIRABLE WHEN APPERANCE IS IMPORTENT 18. STAR SHAKES:-THESE ARE CRACKS WHICH EXTEND FROM BARK TOWARDS THE SAP WOOD.THESE ARE USUALLY CONFINED UPTO THE PLANE OF SAP WOOD.THESE ARE WIDER ON OUTSIDE ENDS AND NARROWER ON INSIDE ENDS.THEY ARE USUALLYFORMED DUE TO EXTREME HEAT OR SEVERE FROST DURING THE CUP SHAKES:-IT APPEARS AS CURVED GROWTH OF TREE SPLIT WHICH PARTLY OR WHOLLY SEPERATES ANNUAL RINGS FROM ONE ANOTHER.IT IS CAUSED DUE TO EXCESSIVE FROST ACTION ON SAP PRESENT IN THE TREE ESPECIALLY WHEN THE TREE IS YOUNG 19. HEART SHAKES:-THESE CRACKS OCCUR IN CENTRE OF CROSS-SECTION OF TREE AND THEY EXTEND FROM PITH TO SAP WOOD IN DIRECTION OF MEDULLARY RAYS.THESE CRACKS OCCUR DUE TO SHRINKAGE OF INTERIOR PART OF TREE WHICH IS APPROACHING MATURITY.THE HEART SHAKE DIVIDE THE TREE CROSSSECTION INTO TWO OR FOUR PARTS. RING SHAKES:-WHEN CUP SHAKES COVER THE ENTIRE ,THEY ARE KNOWN AS RING SHAKES 20. TWISTED FIBRES:-THESE ARE KNOWN AS WANDERING HEARTS AND CAUSED BY TWISTING OF YOUNG TREES BY FAST BLOWING WIND.THE TIMBERS WITH TWISTED FIBRES IS UNSUITABLE FOR SAWING UPSETS:-THESE INDICATE WOOD FIBRES WHICH ARE INJURED BY CRUSHING OR COMPRESSION.THE UPSETS ARE MAINLY DUE TO IMPROPER FELLING OF TREE AND EXPOSURE OF TREE IN ITS YOUNG AGE TO FAST BLOWING WIND BURLS:-THEY ARE PARTICULARLY FORMED WHEN A TREE RECIEVES SHOCK OR INJURY IN ITS YOUNG AGE.DUE TO ITS INJURY,THE GROWTH OF TREE IS COMPLETELY UPSET AND IRREGULAR PROJECTIONS APPEAR ON THE BODY OF 21. BLUE STAINBROWN ROTDRY ROTHEART ROTWET ROTWHITE ROT 22. BLUE STAIN :-THE SAP OF WOOD IS STAINED TO BLUISH COLOUR BY THE ACTION OF CERTAIN TYPE OF FUNGIBROWN ROT :-THE TERM ROT IS USED TO INDICATE DECAY OR DISEASE OF TIMBER,THE FUNGI OF CERTAIN TYPE REMOVES CELLULOSE COMPOUNDS FROM WOOD AND HENCE WOOD ASSUMES THE BROWN COLOUR WHITE ROT:-IT IS JUST OPPOSITE OF BROWN ROT.IN THIS CERTAIN TYPE OF FUNGI ATTACK LIGNIN OF WOOD AND WOOD ASSUMES THE APPEARANCE OF A WHITE MASS CONSISTING OF 23. HEART ROT:-THIS IS FORMED WHEN BRANCH HAS COME OUT OF THE TREE.IN SUCH CASE,THE HEART WOOD IS EXPOSED TO ATTACK OF ATMOSPHERIC AGENTS.ULTIMATELY THE TREE BECOMES WEAK AND IT GIVES HOLLOW SOUND WHEN STRUK WITH HAMMER WET ROT:-SOME KIND OF FUNGI CAUSEDCHEMICAL DECOMPOSITION OF WOOD OF TIMBER AND IN DOING SO CONVERT TIMBER INTO GREYISH BROWN POWDER.IT IS KNOWN AS WET ROT. SOME IMPORTANT POINTS TO BE REMEMBERED ABOUT WET ROT ARE. THE ALTERNATE WET AND DRY CONDITIONS FAVOURS THE DEVELOPMENT OF WET ROT IF UNSEASONED OR IMPROPERLY SEASONED TIMBER ARE EXPOSED TO RAIN AND WIND,THEY BECOME EASILY LIABLE FOR ATTACK OF WET ROT. TO PREVENT WET ROT,THE WELL SEASONED TIMBER SHOULD BE USED FOR EXTERIOR WORK OR FOR UNDERGROUND WORK 24. DRY ROT :- SOME TYPES OF FUNGI FEED ON WOODS AND DURING FEEDING THEY ATTACK ON WOOD AND CONVERT IT INTO DRY POWDER FORM.THIS IS KNOWN AS DRY ROT.THE FOLLOWING FACTS TO BE NOTED. DRY ROT OCCURS AT THE PLACES WHERE THERE IS NO FREE CIRCULATION OF AIR SUCH AS IMPROPERLY VENTILATED BASEMENTS,ROOMS ETC AND DAMPED SITUATION LIKE KITCHEN TOILET ETC. THE UNSESONED SAP WOOD ARE EASILY ATTACKED BY DRY ROT. THE FAVOURABLE CONDITIONS FOR GROWTH OF FUNGUS CAUSING DRY ROT ARE ABSENCE OF SUNLIGHT,DAMPNESS,PRESENCE OF SAP,STAGNANT AIR AND WARMTH. IT IS ALSO CAUSED BY CHARRING,PAINTING AND TARRING THE UNSEASONED TIMBER. THE DRY ROT MAY BE PREVENTED BY USING WELL SEASONED TIMBER FREE FROM SAP. WHEN A PART OF TREE IS SERIOUSLY AFFECTED BY DRY ROT,THE 25. (CAUSED BY)BEETL ESMARINE BOARERSTERMIT ES 26. Flour like powder THEY FORM PIN HOLES OF SIZE ABOUT 2MMDIA IN WOOD TUNNEL FORMATION IS DONE IN SAP WOOD BY LARVAE OF BEETLE CONVERSION OF TIMBER INTO FLOUR LIKE POWDER THEY DO NOT DISTURB OUTER SHELL OR 27. BOAR STHEY ARE FOUND IN SALTY WATER THEY FORM TUNNELS OR BORES TO TAKE SHELTERS DIAMETER AND LENGTH OF HOLES ARE AS HIGH AS 25MM AND 60 MM RESPECTIVELY AFFECTED WOOD LOOSES ITS COLOUR AND STRENGTH NO TIMBER IS COMPLETELY IMMUNE FROM ATTACK OF MARINE BOARERS 28. LIVES IN COLONY AND VERY FAST IN EATING AWAY THE WOOD FROM CORE OF CROSS-SECTION. MAKES TUNNELS IN DIFFERENT DIRECTIONS AND USUALLY NOT DISTURB THE OUTER SHELL OR COVER. THE TIMBER PIECE ATTACKED BY TERMITES MAY LOOK SOUND UNTILL IT COMPLETELY FAILS FEW GOOD TIMBERS LIKE TEAK,SAL,ETC CAN 29. CHIP MARKDIAGONAL GRAINTORN GRAINWAN E 30. CHIP MARK:-THIS DEFECT IS INDICATED BY MARK OR SIGNS PLACED ON FINISHED SURFACE OF TIMBER.THEY MAY BE FORMED BY PLANING MACHINE WANE:-THIS DEFECT IS DENOTED BY PRESENCE OF ORIGINAL ROUNDED SURFACE ON MANUFACTURED 31. DIAGONAL GRAIN:-THE DEFECT IS FORMED DUE TO IMPROPER SAWING SAWING OF TIMBER.IT IS INDICATED BY DIAGONAL MARKS ON STRAIGHT GRAINED SURFACE OF TIMBER TORN GRAIN:-DEFECT CAUSED WHEN A SMALL DEPRESSION IS FORMED ON A FINISHED SURFACE OF TIMBER BY FALLING A TIMBER OR SO TORN GRAIN 32. TWISTCUPBOWSPRIN GSPLITHONEY COMBING 33. BOW:-THIS DEFECT IS INDICATED BY CURVATURE FORMED IN DIRECTION OF LENGTH OF TIMBER CUP:-THIS DEFECT IS INDICATED BY CURVATURE FORMED IN TRANSVERSE 34. SPLIT CHEC KCHECK:-A CRACK WHICH SEPERATES FIBRES OF WOOD.IT DOES NOT EXTEND FROM ONE END TO THE OTHER SPLIT:-WHEN CHECK EXTENDS FROM ONE END TO OTHER,IT IS KNOWN AS A SPLIT 35. TWIST:-WHEN A PIECE OF TIMBER HAS SPIRALLY DISTORTED ALONG ITS LENGTH,IT IS KNOWN AS A TWIST HONEY-COMBING:-DUE TO STRESS DEVOLOPED DURING DRYING,VARIOUS RADIAL AND CIRCULAR CRACKS DEVELOP IN THE INTERIOR PORTION OFHONEY-COMB STRUCTURE 36. Qualities of Good Timber It Should have Straight Fiber Wood Obtained from near the pith is always better than the rest of the tree. It should be free from knots. It should not posses natural defects. On sawing it should give a sweet smell. It should have regular annual rings. It should not clot the saw teeth during sawing. It should be Strong and heavy. It should not split when nails are driven in to it. It should bear high resistance shock and stresses. 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. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 37. Selection of Timber 1. Durability 2.workability 3. Weight 4. Hardness 5.Cohesivness 6. Elasticity 7. Type of texture 8. Type of grains 9. Resistance to fire 10.Resistance to various stresses 11. Ability to retain shape 12. Easy Polishing 38. Seasoning of Timber Seasoning of timber is the process of drying orremoving the moisture or Sap presents in a freshly felled timber, under more or less controlled conditions. Freshly felled timber contains a large humidity ofmoisture 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. 39. Advantages of Seasoning Wood becomes hard, more durable, resistanceto 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. 40. 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 41. 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 Centimeters for free circulation of air. Wood fit for carpenters work after 2 years and for painters work after 4 years. 42. 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) Rigid control cannot be exercised (iv) Block the capital a long time. (v) Timber may get damaged by insects and fungi during seasoning period. 43. (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. 44. 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 thedurability of the timber. (ii) The timber is redder brittle. 45. 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 wrapping 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. 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. 46. Kiln Method 47. 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 so chances to check regularlyseasoning defects such as wrapping, internal cracks, surface cracks etc. 48. 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.( C) 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, lack of control moisture content, sudden drying damage wooden fibers. 49. Electrical Seasoning 50. Seasoning Videos A rtificial seasoning of timber-1.mp4A rtificial seasoning of timber.mp4 51. Timber Tress of India 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.Deodar Babul Teak Shishum Mango Mahogani Walnut Mulberry Sal Chir Kail Bamboo 52. Wood Based Products Plywood Boards(i) Block Board (ii) Batton Board (iii) Fiber Board 53. Plywood Plywood is made of three or more number of oddlayers, jointed together by gluing and pressing. The central layer is called core, the outer layer is face plys and intermediate layers as cross bands.Advantages 1. lighter weight, much stronger than solid stockof same thickness. 2. It can be made in very large sizes. 3. Easily worked and bend into shapes of different designs. 4. Top veeners can be given fine decorative effects to give attractive appearance. 54. Block Board Blockboard is a wood based panel, made up of acore of softwood strips glued together. The strips may be up to about 28mm wide and are placed edge to edge and sandwiched between veneers of softwood, hardwood or thin MDF or particleboard, glued under high pressure. The internal strips are generally made of light weight poplar wood. Blockboard is used to make doors, tables, shelves, paneling and partition walls. It is normally used for interior usages, due to the type of glues used. To achieve maximum strength, it is important to ensure that the core runs lengthways. Blockboard (also called lumber core) has very good screw holding and can be considered as solid wood; it has a good resistance to warping. 55. Fiberboard Fiberboard is a type of engineered wood product thatis made out of wood fibers. Types of fiberboard (in order of increasing density) include particle board, medium-density fiberboard, and hardboard. Fiberboard is sometimes used as a synonym for particle board, but particle board usually refers to lowdensity fiberboard. Plywood is not a type of fiberboard, as it is made of thin sheets of wood, not wood fibers or particles. Fiberboard, particularly medium-density fiberboard (MDF), is heavily used in the furniture industry. For pieces that will be visible, a veneer of wood is often glued onto fiberboard to give it the appearance of conventional wood. Fiberboard is also used in the auto industry to create free-form shapes such as dashboards, rear parcel shelves, and inner door shells. These pieces are usually covered with a skin, foil, or fabric such as cloth, suede, leather, or polyvinyl chloride. 56. Fiber Board 57. Batten Board A batten is a thin strip of solid material, typically madefrom wood, plastic or metal. Battens are used in building construction and various other fields as both structural and purely cosmetic elements. In the steel industry, battens may also be referred to as "top hats", in reference to the profile of the metal. In sailing, battens are long, thin strips (usually fiberglass or some similar material nowadays, but historically wooden) used to support the roach of a sail. They are also used on tall ships to form the ladders up the shrouds in a fashion similar to ratlines. They are also used to help secure tarpaulinsover hatches, thus giving rise to the common phrase "batten down the hatches!", meaning to secure the hatches against an approaching storm. Used by analogy in non-sailing contexts, it means to prepare to weather a coming storm, whether that storm is metaphorical or real. In cabinetry, battens may be used to strengthen panels 58. 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 59. Measuring and Marking Tools: used for measuring, marking, setting out angles and parallel lines and testing Measuring Tools (a) Folding Rule (b) Measuring Taps (c) Try square (d) MITRE Square (e) Bevel square Marking Tools (f) Marking Knife or Scriber (g) Marking Gauge (f) Mortise Gauge (e) Cutting Gauge 60. Measuring Tool: (a) Folding Rule(b) Measuring Steel Tap 61. Try Square: -used for measuring and setting outdimensions, 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. It consists of a steel Blade fitting into a wooden or metallic stock at right angle to it. Mitre Square: measuse aand mark angle at 450 Bevel Sqaure :- measure 0 to 180 degree angle. 62. Marking tool: Marking Knife or Scriber: It has sharp conical edgesused 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. 63. 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. 64. 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 65. Holding and Supporting Tools Carpenters bench and bench Hook 2. Carpenters Vice 3. Bar or T- Clamp and C-Clamp 4. Hand Screw 1. 66. Carpenters bench and bench Hook:- It is table of rigid construction made of hard wood about 180cmx 120cmx90cm(H) size. Four carpenter vice are fitted on opposite sides of bench to hold the jobs during operation. 67. Carpenters 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. 68. Clamps and screws: These are used by carpenters for holding and supporting wood pieces in position for carrying out different operations. 69. Cutting Tools Cutting tools may classified as follows:-Saws 2. Chisels 3. Axe 1. 70. 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 71. Rip saw Cross-cut saw Tenon saw 72. 1.Dovetail saw2.Compass or turning saw3.Keyhole saw 73. 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)(ii) (iii) (iv)(v) (vi)Firmer chisel Bevelled edge firmer chisel Parting chisel Mortise Chisel Socket chisel Gauge chisel 74. (i)Firmer chisel(ii) Bevelled edge firmerchisel(iii) Parting chisel 75. (i)Mortise Chisel(ii) Socket chisel(iii) Gauge chisel 76. 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 adzeSide AxeAdze 77. 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.Wooden Jack Plane 2. Iron Jack Plane 3. Smoothing Plane 1. 78. Boring and Drilling Tools:- for producing holes in wood. Auger Gimlet Bradwal Brace and Bits Hand Drill 79. Gimlet AugerBradwalBrace and 80. Hand Drill 81. Striking Tools Mallet 2. Claw Hammer 3. Peen Hammer 1.MalletClaw HammerPeen Hammer 82. Miscellaneous Tools 1.Screw Driver2.Pincer3.Rasp file 83. Wood Working Processes 1. 2. 3. 4. 5.6. 7. 8. 9.Marking and Laying out Sawing Planning Mortising and Tenoning Boring Grooving and Tonguening Moulding Rebating Recessing 84. Carpentry Joints 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 1. 85. 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 timber framing, 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 86. Half laps (T-lap Joint)Cross Lap JointEnd Lap Joint 87. 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. Use for: Internal cabinet frames Visible frames when the frame members are to be shaped. 88. Cross lap The main difference between this and the basic halflap 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. Use for: Internal cabinet frames Simple framing and bracing 89. Dovetail This is a lap in which the housing has been cut atan angle which resists withdrawal of the stem from the cross-piece. Use for: Framing applications where tension forces could pull the joint apart 90. Dove Tail Joint 91. Mitre half lap This is a variation of the end lap which showsa 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 92. mortise and tenon joint The mortise and tenon joint has been used forthousands 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. 93. Briddle JointDovel JointGrooving and 94. HIGHLIGHTS Timber is the wood suitable for building or engineering purposes and it is applied to trees measuring not less than 0.5 m in girth. 2. A good timber should have a uniform colour, smell sweet, be sonorous when struck, have straight and closed fibers, be heavy in weight, and be free from flaws etc. 3. The tress may be exogenous or endogenous. The trees should be felled when they have just matured or when they are very near to maturity. 1. 95. HIGHLIGHTS 4. The most common defects in timber are : Heart shakes, star shakes, cup shakes, radial shakes, rind galls, upset, twisted fibers, burns, wind cracks, knots, honeycombing, end splits, deadwood, druxiness. 5. Seasoning of timber is the process of drying timber or removing moister or sap, present in a freshly felled timber, under more or less controlled conditions.6. Seasoning of timber decreases the weight of timber, improves its working qualities, enables it to be easily painted, polished and preserved and provides its dimensional stability. 96. HIGHLIGHTS 7. Seasoning of timber may be carried outin following two ways: (i) Natural Seasoning(a) Air Drying/ Seasoning (b) Water Seasoning (ii) Artificial Seasoning (a) Kiln Seasoning (b) Chemical Seasoning (c) Electrical Seasoning8. Decay of timber may be caused by : Moister, imperfect seasoning, alternation of dry and wet states, vegetable growth, attacks of insects etc, bad storage or stacking of timber etc.9. Diseases of wood are : Dry Rot: It is decomposition of felled timber by the action of various fungi which feed upon the wood and reduce it to a dry powdery condition. 97. HIGHLIGHTS 10. The different methods of preservation of timber are : Tarring, charring, painting, creasoting, Ascue treatment, fire proofing and Abels process. 11. Veneers are the thin sheets or slices of wood of superior quality, having thickiness varying from 0.4mm to 6 mm or more. 12. Plywood is made by cementing together several layers of wood which may be thin veneers or thicker boards. 98. HIGHLIGHTS 13. Wood working tools are classified asfollows: Measuring and marking tools, holding and supporting tools, cutting tools, Planning tools, Boring and Drilling Tools, Striking tools, Miscellaneous tools. 14. Wood working processes: Marking and laying out, Sawing, Planning, Mortising and Tenoning, Boring, Grooving and tongueing, Moulding, Rebatting, Recessing. 15. Classification of Joints: Lap Joints, Dowel Joint, Grooved Joint , Miter Joint, Mortise and Tenon Joint, Dovetail joints etc.