TLE10_IA_CarpentryNC2_Q1MOD2_Properties-and-Defects-of-Wood_v3 (1) PDF
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2020
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This technology and livelihood education (TLE) module for Grade 10 carpentry covers the properties and defects of wood. It includes activities, exercises, and assessments to measure learner understanding.
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10 Technology and Livelihood Education Quarter 1 - Module 2 Prepare Tools, Equipment and Materials for Staking-out Building Lines (Identifying properties and defects of wood) CARPENTRY NC II CO_Q1_TLE 10_Module 2 ...
10 Technology and Livelihood Education Quarter 1 - Module 2 Prepare Tools, Equipment and Materials for Staking-out Building Lines (Identifying properties and defects of wood) CARPENTRY NC II CO_Q1_TLE 10_Module 2 10 Technology and Livelihood Education Quarter 1 - Module 2 Prepare Tools, Equipment and Materials for Staking-out Building Lines (Identifying properties and defects of wood) CARPENTRY NC II TLE Carpentry – Grade 10 Alternative Delivery Mode Quarter 1 – Module 2: Prepare Tools, Equipment and Materials for Staking-out Building Lines (Identifying properties and defects of wood) First Edition, 2020 Republic Act 8293, section 176 states that: No copyright shall subsist in any work of the Government of the Philippines. However, prior approval of the government agency or office wherein the work is created shall be necessary for exploitation of such work for profit. Such agency or office may, among other things, impose as a condition the payment of royalties. Borrowed materials (i.e., songs, stories, poems, pictures, photos, brand names, trademarks, etc.) included in this module are owned by their respective copyright holders. Every effort has been exerted to locate and seek permission to use these materials from their respective copyright owners. The publisher and authors do not represent nor claim ownership over them. Published by the Department of Education Secretary: Leonor Magtolis Briones Undersecretary: Diosdado M. San Antonio Development Team of the Module Writer: Nestor O. Dawaton Editors: Reviewer: Jonalyn C. Ambrona Martina Tibangay Baby Lourdes Balian Illustrator: Layout Artist: Management Team: Estela Leon-Cariño Carmel F. Meris Rosita C. Agnasi Romulo A. Galnawan Evelyn G. Ganotice Martina L. Tibangay Noel D. Diosan Printed in the Philippines by: Department of Education – Cordillera Administrative Region Office Address: Wangal, La Trinidad, Benguet Telefax: (074) -422 -4074 E-mail Address: [email protected] iv Introductory Message This Self-Learning Module (SLM) is prepared so that you, our dear learners, can continue your studies and learn while at home. Activities, questions, directions, exercises, and discussions are carefully stated for you to understand each lesson. Each SLMS is composed of different parts. Each part shall guide you step- by-step as you discover and understand the lesson prepared for you. Pre-tests are provided to measure your prior knowledge on lessons in each SLM. This will tell you if you need to proceed on completing this module or if you need to ask your facilitator or your teacher’s assistance for better understanding of the lesson. At the end of each module, you need to answer the post-test to self- check your learning. Answer keys are provided for each activity and test. We trust that you will be honest in using these. In addition to the material in the main text, Notes to the Teacher are also provided to our facilitators and parents for strategies and reminders on how they can best help you on your home-based learning. Please use this module with care. Do not put unnecessary marks on any part of this SLM. Use a separate sheet of paper in answering the exercises and test. And read the instructions carefully before performing each task. If you have questions in using this SLM or any difficulty in answering the tasks in this module, do not hesitate to consult your teacher or facilitator. Thank you. Notes to the Teacher This contains helpful tips or strategies that will help you in guiding the learner. For the facilitator: Hi, as a facilitator you are expected to orient the learners on how to use this module. You also need to keep track of the learners' progress while allowing them to manage their own learning. Kindly, advise the learner’s parents or guardians of the same procedure since they will be the primary supporters in the learners’ progress. Please, do not forget to remind the learner to use separate sheets in answering all of the activities found in the learning module. iii For the learner: Hello learner, Welcome to the Carpentry NC II Alternative Delivery Mode (ADM) Module on Identifying properties and defects of wood. I hope you are ready to progress in your Grade 10 TLE in Carpentry NC II with this learning module. This is designed to provide you with interactive tasks to further develop the desired learning competencies prescribed in our curriculum. With this, you are expected to appreciate staking through the information and activity given. This module has the following parts and corresponding icons: ICON LABEL DETAIL What I Need to Know This contains the learning objectives which you need to accomplish. What I know This evaluates what you know about the lesson you are to learn. What’s In This connects the current lesson with a topic necessary in your understanding. What’s New This introduces the lesson through an activity. What Is It This contains a brief discussion of the learning module lesson. What’s More These are activities to check your understanding of the lesson. What I Have Learned This summarizes the important ideas presented in the lesson. What I Can Do This is a real-life application of what you have learned. Assessment This is a post assessment of what you have learned. Additional Activity This is an activity that will strengthen your knowledge about the lesson. At the end of this module you will also find: References This is a list of all sources used in developing this module. iv TABLE OF CONTENTS What I Need to Know.............................................. Error! Bookmark not defined. What I Know....................................................................................................... 2 What’s In............................................................................................................ 3 What’s New......................................................................................................... 3 What Is It............................................................................................................ 4 What’s More........................................................................................................ 8 What I Have Learned........................................................................................... 9 What I Can Do.................................................................................................. 10 Post-Assessment............................................................................................... 11 Additional Activity............................................................................................. 12 Answer Key....................................................................................................... 13 References........................................................................................................ 14 v Lesson Identifying properties and 1 defects of Wood The following are some reminders in using this module: 1. Use the module with care. Do not put unnecessary mark/s on any part of the module. Use a separate sheet of paper in answering the exercises. 2. Don’t forget to answer What I Know before moving on to the other activities included in the module. 3. Read the instruction carefully before doing each task. 4. Observe honesty and integrity in doing the tasks and checking your answers. 5. Finish the task at hand before proceeding to the next. 6. Return this module to your teacher/facilitator once you are through with it. If you encounter any difficulty in answering the tasks in this module, do not hesitate to consult your teacher or facilitator. Always bear in mind that you are not alone. We hope that through this material, you will experience meaningful learning and gain deep understanding of the relevant competencies. You can do it! What I Need to Know This module was designed and written to guide you to acquire the learning competencies and develop your skills in preparing tools, equipment and materials for staking-out building lines. The scope of this module permits it to be used in many different learning situations. The language used recognizes the diverse vocabulary level of students. The lessons are arranged to follow the standard sequence of the course. However, the order in which you read the module can be changed to correspond with the textbook you are now using. Learning Objectives: Prepare tools, equipment and materials for staking out building lines (TLE_IACP9-12BLIa-h-1) After going through this module, you are expected to: 1. identify the properties of wood for staking out building lines; 2. describe wood defects; and, 3. value the importance of using wood of good quality. 1 What I Know Pre-Test Multiple Choice. Directions. Read the following questions carefully, select the letter of the correct answer and write in your activity notebook. 1. It is the warping of lumber where the ends twist in opposite direction. A. Bow C. Twist B. Crock D. Wane 2. It is the longitudinal separation of the fibers which extends to the opposite face of a piece of sawn timber. A. Cupping C. Twist B. Split D. Crock 3. Is the ratio of the mass of water contained in the mass of the same sample of dry wood? A. Moisture content C. Density B. Shrinkage D. Mass 4. Mechanical properties of wood include ____________________________. A. Elasticity C. Strength B. Vibration D. All of these 5. It is used to cut pegs for stake out. A. Bolo C. Knife B. Cross cut saw D. adze 6. It is a milled or processed piece of wood and ready to use. A. Plywood C. Timber B. Lumber D. Plank 7. It is used for marking straight lines on a long piece of stock or lumber. A. Pencil C. Chalk line B. Chalk D. Charcoal 8. It is use to drive pegs for stake out. A. Claw hammer C. Ball peen hammer B. Framing hammer D. Sledge hammer 9. A material used for laying out building lines over the batter board. A. Nylon String /Tansi C. Chalk line B. Plastic twine chord D. Nails 10. It occurs when wood loses moisture below the fiber saturation point. A. Cleavability C. Permeability B. Knot D. Shrinkage 11. It is the resistance of wood to cleavage along the grain. A. Cleavability C. Permeability B. Knot D. Shrinkage 12. It is the wood defects caused by insects. A. Crack C. Twist B. Crock D. Wood bores 2 13. It is influenced by the anatomy of wood cells. A. Cleavability C. Permeability B. Knot D. Shrinkage 14. Which of the following is NOT a wood defect? A. Bow C. Knot B. Crook or Crown D. Shearing Strength 15. Wood defects ___ A. are abnormalities in wood. C. reduce the strength of wood B. lower the economic value of wood D. all of the above What’s In This Module is a useful document which you can use to add more knowledge and skills that you acquired in the previous lesson. It includes instructions and procedure on how to perform the different learning outcomes. The unit of competency contains the knowledge, skills, and attitudes required to know the physical, defects and properties of wood for staking-out building lines course. You are required to go through a series of learning activities in order to complete each of the learning outcomes of this module. What’s New Activity 1. How do you do? Copy the template in your activity notebook and fill with the needed information. List the different tools, materials and equipment which you can see in your house and write its uses according to what you know. Name of tools, materials and Write each use according to its equipment use in Carpentry specification. 3 What Is It Wood is obviously both a common and a historical choice as a building material. However, in the past few decades, there has been a move away from wood in favor of engineered products or metals like aluminum. While the desire to not rely on the world’s forests for building demands is well-intentioned, the advantages of wood as a building material still outweigh other products on the market when looking at the environmental impact and performance. In the construction of formworks wood is the most important material needed. You will be selecting the appropriate lumber for every part of the forms. You also need to learn how to identify the different defects of wood which may cause unnecessary failures in the assembling process. Knowing the physical properties of wood can help guide us in choosing good, quality lumber for our carpentry works. In this lesson, we will not only learn the different physical properties of wood, we will also discuss the different kinds of wood defects that we need to look out for and avoid. Quality should never be compromised by cheap but defective lumber. PHYSICAL PROPERTIES OF WOOD 1. Strength Physically, wood is strong and stiff but, compared to a material like steel, it's also light and flexible. It has another interesting property too. Metals, plastics, and ceramics tend to have a fairly uniform inner structure and that makes them isotropic: they behave exactly the same way in all directions. Strength is the general term used in reference to the ability of wood to resist stresses and strain. Different wood varies materially in the following manner. a. Wood is resistant to compression along the fiber. b. Stiffness or the ability to resist bending as in floor joist and beam supporting heavy load. c. Strength in tension or the ability to resist in lengthwise d. Shearing strength or the ability of the fibers to resist rupture along across the grain 2. Moisture is an important factor in strength of wood, thus to a certain extent, strength increase with the degree of seasoning of wood a. MOISTURE CONTENT is the ratio of the mass of water contain in the mass of same sample of dry wood. b. SHRINKAGE occurs when wood loses moisture below the fiber saturation point. 4 3. Knots or other defects also influence strength. The size, character and location of the knots are important. EXAMPLE in cross bending strength, knots on the upper surface of the beam do not detract from the strength as much as on the lower part of the beam 4. Weight of wood is also important, Heavy wood are usually strong and light wood are usually weak. 5. Hardness is expressed as resistance to indentation or to the saw or ax across the grain. Hardness dependent largely on weight, structure elements of the wood and degree of seasoning. 6. Durability as applied to wood, means the ability to resist decay or simply the length of life of a certain timber under given conditions. 7. Cleavability is the resistance of wood to cleavage along the grain. 8. Color is often a means of identification of wood, as mentioned earlier, heartwood is generally much darker in color than sapwood. 9. Permeability is influence by the anatomy of wood cells. 10. Mass properties of wood are conductivity, heat and coefficient of thermal expansion. 11. Electrical properties of wood are dielectric constant and the dielectric power factor alternating current. MECHANICAL PROPERTIES OF WOOD: 1. ELASTICITY of wood depends on grain orientation, moisture, species, temperature, and rate of loading 2. STRENGTH depends upon the rate of loading species, moisture, contents, orientation, temperature, size and location of natural characteristics such as knots and species size. 3. VIBRATION damping and sound velocity are two primary vibration phenomena of interest in structural application. WOOD DEFECTS Wood defects are abnormalities which tend to lower the economic value or decorative value of wood and also reduces the strength of wood. The main defects of wood include knots, cracks, fungal damage, warping, slanting of grain, and wormholes. A knot is a part of a branch embedded in wood. A crook or crown is a defect found in a board that is bent end-to-end in the direction of the tall ends of a board as it continues down the length of the board. 5 Bow A board that rocks from end to end when laid on one face. Curvature is formed in direction of the length of the sawn timber. Cupping This often occurs when one side dries faster the other. Where the face of a board warps up across its width such that if one looks at the end of the board, it will look like a shallow letter “U”. Checking A crack in the wood structure of a piece, running lengthwise usually caused by rapid seasoning. Split A longitudinal separation of the fibers which extends to the opposite face of a piece of sawn timber. Wane The presence of bark or absence of wood on corners of a piece of lumber. Blue Stain A discoloration that penetrates the wood fiber. It can be any color other than the natural color of the piece in which it is found. It is classified as light, medium, or heavy and is generally blue or brown. 6 Machine Burn A darkening of the wood due to overheating by the machine knives or rolls when pieces are stopped in a machine. Pitch An accumulation of resinous material on the surface or in pockets below the surface of wood. It is also called gum or sap. Tight Knot A knot fixed by growth or position in the wood structure so that it firmly places in the its surrounding wood. Wood bores Holes in the wood caused by insects and beetles. Twist Warping in lumber where the ends twist in opposite directions. 7 What’s More Activity 2: Identification of Wood Defects Direction: Identify the wood defects as shown on the picture below. Write your answer on your activity notebook.. 1. _________________________________ 5. _____________________________ _ 2. ______________________________ 6. _________________________________ ___ 7. _________________________________ 3. _________________________________ 4. _________________________________ 8. _________________________________ 8 What I Have Learned Activity 3: HUNT ME Directions: Hunt the words in the box associated in our lesson. Write your answers in your Activity Notebook. 9 What I Can Do Activity 4. DRAW ME In a sheet of paper, draw the types of wood defects. Your output will be rated using the rubric below. Criteria Excellent Good Fair Poor Subject Subject Some subject Subject knowledge is knowledge is knowledge is knowledge is evident evident in evident. Some not evident. throughout the much of the Information is Information is Knowledge project. All project. Most confusing, confusing, information is information is incorrect, or incorrect, or clear, clear, flawed. flawed. appropriate, and appropriate, correct and correct. Drawing looks The sequence The sequence The sequence perfect with no of information of information of information technical is logical. is somewhat is not logical. Drawing problems. For Views and logical. Views are not Accuracy example, there Labels of most evident. are no errors in information measurement, are clear style. The sequence of Project runs Project runs Project does drawing adequately minimally. not run information is with minor There aresatisfactorily. correct. technical many There are too Drawing problems. technical many Organization problems technical when viewing problems to the project. view the project. The project The project is The work The work is a shows total mostly shows Some minimally Completeness completeness. complete. level of completed. completeness The project The project is The work The work is a shows total mostly clean. shows some minimally Cleanliness cleanliness. level of clean. cleanliness Legend: SCALE DISCRIPTION POINTS 4 Excellent 95-100 3 Good 86-94 2 Fair 81-85 1 Poor 75-80 10 Post-Assessment Multiple Choice. Directions. Read the following questions carefully, select the letter of the correct answer and write in your activity notebook. 1. Mechanical properties of wood include ____________________________. A. Elasticity C. Strength B. Vibration D. All of these 2. It is used to cut pegs for stake out. A. Knife C. Bolo B. Cross cut saw D. adze 3. Wood defects ___ A. are abnormalities in wood C. reduce the strength of wood B. lower the economic value of wood D. all of the above 4. It is a milled or processed piece of wood and ready to use. A. Lumber C. Timber B. Plywood D. Plank 5. It is used for marking straight lines on a long piece of stock or lumber. A. Pencil C. Chalk B. Chalk line D. Charcoal 6. It is the longitudinal separation of the fibers which extends to the opposite face of a piece of sawn timber. A. Cupping C. Twist B. Split D. Crock 7. It is use to drive pegs for stake out. A. Claw hammer C. Ball peen hammer B. Framing hammer D. Sledge hammer 8. A material used for laying out building lines over the batter board. A. Nails C. Chalk line B. Plastic twine chord D. Nylon String /Tansi 9. It occurs when wood loses moisture below the fiber saturation point. A. Shrinkage C. Permeability B. Knot D. Cleavability 10. It is the resistance of wood to cleavage along the grain. A. Cleavability C. Permeability B. Knot D. Shrinkage 11. Is the ratio of the mass of water contained in the mass of the same sample of dry wood? A. Moisture content C. Density B. Shrinkage D. Mass 12. It is the wood defects caused by insects. A. Crack C. Twist B. Crock D. Wood bores 11 13. It is the warping of lumber where the ends twist in opposite direction. A. Bow C. Twist B. Crock D. Wane 14. It is influenced by the anatomy of wood cells. A. Cleavability C. Permeability B. Knot D. Shrinkage 15. Which of the following is NOT a wood defect? A. Bow C. Knot B. Crook or Crown D. shearing Strength Additional Activity Activity 5. Reality Check Answer the following questions about properties and defects of wood. Write your answer in your activity notebook. 1. What is wood defect? _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ 2. What are the mechanical properties of wood? _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ 3. What are the benefits of this topics especially in carpentry students? and why? ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ _____________________________________________ 12 13 ANSWER KEY ANSWER KEY What I Have Learned What I Know: Pre-test Answers may vary 1. C 2. B What I Can Do 3. A Refer to Rubric 4. D 5. A Post Assessment 6. B 1. D 7. C 2. C 8. D 3. D 9. A 4. A 10. D 5. B 11. A 6. B 12. D 7. D 13. C 8. D 14. D 9. A 15. D 10. A 11. A What New 12. D Answers may vary 13. C 14. C What’s More 15. D 1. Twist 2. Crook Additional Activity 3. Split Answers may vary 4. Machine burn 5. Bow 6. Cupping 7. Wane Answer Key References Competency Based Learning Materials (CBLM) Carpentry NC II, 2009 Fajardo Jr., Max B. Simplified Methods on Building Construction, second edition. Quezon City: 5138 Merchandizing, 1983. https://images.app.goo.gl/MB68qY2byaH3DFSNA https://i2.wp.com/theconstructor.org/wp-content/uploads/2018/03/timber- warp.jpg?resize=386%2C254&ssl=1 https://i0.wp.com/theconstructor.org/wp-content/uploads/2018/03/timber- bow.jpg?resize=387%2C163&ssl=1 https://i.pinimg.com/originals/c2/a1/89/c2a1897938c1b4ff067acfd255842108.jp g https://woodproducts.onlineexpos.com/media/keys/292/1.jpg http://images.meredith.com/wood/images/2007/03/p_crookdefect.jpg https://www.wood-database.com/wp-content/uploads/pitch-pine-sealed.jpg https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.woodworkersjourna l.com%2Fquickly-lumber-treated-prevent- checking%2F&psig=AOvVaw1_ExEVynXmb2WAFR0YZylA&ust=1626697062 502000&source=images&cd=vfe&ved=0CAgQjRxqFwoTCOja94Tc7PECFQAA AAAdAAAAABAD https://i0.wp.com/theconstructor.org/wp-content/uploads/2018/03/timber- cup.jpg?resize=378%2C213&ssl=1 14 For inquiries or feedback, please write or call: Department of Education - Bureau of Learning Resources (DepEd-BLR) Ground Floor, Bonifacio Bldg., DepEd Complex Meralco Avenue, Pasig City, Philippines 1600 Telefax: (632) 8634-1072; 8634-1054; 8631-4985 Email Address: [email protected] 15 * [email protected] Telefax: (632) 8634-1072; 8634-1054; 8631-4985