INFO-SHEET-2-Common-Competency_LNNCHS PDF

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This document is a competency-based learning material about performing mensuration and calculations for technical drafting. It includes information on how to use the learning material and describes the different learning activities.

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Competency Based Learning Material Sector : CONSTRUCTION SECTOR Qualification Title : TECHNICAL DRAFTING NCII PERFORM MENSURATION AND Unit of Competency : CALCULATIONS PERFORMING MENSURATI...

Competency Based Learning Material Sector : CONSTRUCTION SECTOR Qualification Title : TECHNICAL DRAFTING NCII PERFORM MENSURATION AND Unit of Competency : CALCULATIONS PERFORMING MENSURATION AND Module Title : CALCULATIONS Document No. Date complied: Issued by: June 2024 Perform mensuration Page 1 of 70 and calculations Complied by: Kristine M. Capao Revision # HOW TO USE THIS COMPETENCY BASED LEARNING MATERIAL Welcome to the module in Performing Mensuration and Calculations. This module contains training materials and activities for you to complete. The unit of competency “Perform Mensuration and Calculations" contains knowledge, skills and attitudes required for TECHNICAL DRAFTING NCII. You are required to go through a series of learning activities in order to complete each learning outcome of the module. In each learning outcome are Information Sheets, Self-Checks, Task Sheets, and Job Sheets. Follow these activities on your own. If you have questions, don’t hesitate to ask your facilitator for assistance. The goal of this course is the development of practical skills. To gain these skills, you must learn basic concepts and terminologies. For the most part, you'll get this information from the Information Sheets and TESDA Website, www.tesda.gov.ph This module is prepared to help you achieve the required competency, in “Perform Mensuration and Calculations". This will be the source of information for you to acquire knowledge and skills in this particular competency independently and at your own pace, with minimum supervision or help from your instructor. Remember to: Work through all the information and complete the activities in each section. Read information sheets and complete the self-check. Suggested references are included to supplement the materials provided in this module. Most probably your trainer will also be your supervisor or manager. He/she is there to support you and show you the correct way to do things. You will be given plenty of opportunity to ask questions and practice on the job. Make sure you practice your new skills during regular work shifts. This way you will improve both your speed and memory and also your confidence. Document No. Date complied: Issued by: June 2024 Perform mensuration Page 2 of 70 and calculations Complied by: Kristine M. Capao Revision # Use the Self-checks, Task Sheets or Job Sheets at the end of each section to test your own progress. When you feel confident that you have had sufficient practice, ask your Trainer to evaluate you. The results of your assessment will be recorded in your Progress Chart and Accomplishment Chart. You need to complete this module before you can perform the next module. Document No. Date complied: Issued by: June 2024 Perform mensuration Page 3 of 70 and calculations Complied by: Kristine M. Capao Revision # TECHNICAL DRAFTING NC II COMPETENCY-BASED LEARNING MATERIALS List of Competencies No. Unit of Competency Module Title Code Performing Perform Mensuration 1. Mensuration and and Calculations CON311203 Calculations Interpret Technical Interpret Technical 2. CON311202 Drawings and Plans Drawings and Plans 3. Apply Quality Apply Quality FUR714202 Standards Standards 4. Operate Personal Operate Personal ICT311201 Computer Computer Document No. Date complied: Issued by: June 2024 Perform mensuration Page 4 of 70 and calculations Complied by: Kristine M. Capao Revision # MODULE CONTENT UNIT OF COMPETENCY : Interpret Technical Drawings and Plans MODULE TITLE : Interpreting Technical Drawings and Plans MODULE DESCRIPTOR : This unit covers the knowledge, skills and attitudes on analyzing and interpreting symbols, data and work plan based on the required performance standards. NOMINAL DURATION: 8 hrs. LEARNING OUTCOMES: At the end of this module, you MUST be able to: 1. Analyze signs, symbol and data 2. Interpret technical drawings and plans ASSESSMENT CRITERIA: 1. Technical plans are obtained according to job requirements. 2. Signs, symbols, and data are identified according to job specifications. 3. Signs, symbols and data are determined according to classification or as appropriate in drawing. 4. Necessary tools, materials and equipment are identified according to the plan. 5. Supplies and materials are listed according to specifications. 6. Components, assemblies or objects are recognized as required. 7. Dimensions are identified as appropriate to the plan. 8. Specification details are matched with existing/available resources and in line with job requirements. 9. Work plan is drawn following the specifications. 10. Apply correct freehand sketching in accordance with the job requirements. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 5 of 70 calculations Complied by: Kristine M. Capao Revision # LEARNING OUTCOME NO. 1 Analyze Signs, Symbol and Data Contents: 1. Orthographic Projection 2. Pictorial Drawing 3. Dimensioning 4. Technical Plans, Drawing Symbols and Signs Assessment Criteria 1. Technical plans are obtained according to job requirements. 2. Signs, symbols, and data are identified according to job specifications. 3. Sign, symbols and data are determined according to classification or as appropriate in drawing. Conditions The student/trainee must be provided with the following: ▪ Classroom for discussion ▪ Workplace Location ▪ Plans ▪ Measuring instruments ▪ Instructional materials relevant to the proposed activity. Assessment Method: 1. Practical Exam 2. Direct observation 3. Written test/questioning Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 6 of 70 calculations Complied by: Kristine M. Capao Revision # Learning Experiences Learning Outcome 1: Analyze Signs, Symbol and Data Learning Activities Special Instructions 1. Orthographic Projection a. Read Information Sheet 2.1-1 Read and understand the on Orthographic Projection. information sheet. If you feel you have already familiarized yourself with the Orthographic Projection, b. Answer Self-Check 2.1-1. you can now answer self-check 2.1- 1. c. Perform Operation Sheet 2.1- Perform Operation Sheet 2.1-1 on 1 Sketching Three Main Views of an Object and show your output to your trainer for feedback / evaluation and recording. 2. Pictorial Drawing a. Read Information Sheet 2.1-2 Read and understand the on Pictorial Drawing. information sheet. If you feel you have already familiarized yourself with the Pictorial Drawing, you can now answer self-check 2.1-2. b. Answer Self-Check 2.1-2. c. Perform Operation Sheet 2.1- Perform Job Sheet 2.1-2 on 2 Pictorial Drawing of an Object and show your output to your trainer for feedback / evaluation and recording. d. Perform Operation Sheet 2.1- Perform Job Sheet 2.1-3 on 3 Pictorial Drawing of an Object and show your output to your trainer for feedback / evaluation and recording. 3. Dimensioning a. Read Information Sheet 2.1-3 Read and understand the on Dimensioning. information sheet. If you feel you have already familiarized yourself with the Pictorial Drawing, you can now answer self-check 2.1-3. b. Answer Self-Check 2.1-3. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 7 of 70 calculations Complied by: Kristine M. Capao Revision # 4. Technical Plans, Drawing Symbols and Signs Read and understand the a. Read Information Sheet 2.1-4 information sheet. If you feel you on Technical Plans. have already familiarized yourself with the Technical Plans, you can now answer self-check 2.1-4. b. Answer Self-Check 2.1-4. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 8 of 70 calculations Complied by: Kristine M. Capao Revision # INFORMATION SHEET 2-1.1 Orthographic Projection Learning Objectives: After reading this INFORMATION SHEET, YOU MUST be able to: 1. Understand and differentiate orthographic projection from other projection methods. 2. Identify and interpret standard views, including front, top, and side views. 3. Create and accurately represent objects using orthographic projections. 4. Use drawing tools and materials effectively for precise drawings. Theories and Principles of Orthographic Projection Multi-view drawing is a drawing that shows more than one view of an object. Orthographic projection is a system for graphical representation of an object by a line drawing on a flat surface. Orthographic Projection An orthographic projection is a representation of separate views of an object on a two-dimensional surface. It reveals the width, depth and height of the object. Ortho means “straight or at right angle” and graphic means “written or drawn”. Projection comes from two Latin words: “pro,” meaning “forward,” and “jacere,”meaning “to throw.” The projection is achieved by viewing the object from a point assumed to be at infinity(an indefinitely great distance away). The line of sight or projectors are parallel to each otherand perpendicular to the plane of projection. Figure 2.1-1 Visualizing one view of an orthographic projection Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 9 of 70 calculations Complied by: Kristine M. Capao Revision # Steps in Selecting Correct Views of an Object 1. Select the number of views necessary to represent the object. This may require only one view or as many as all six views. Only draw as many views as are necessary. 2. Select the front view which: a. Best describes contour shape. b. Contains the least number of hidden lines. c. Is usually the longest view. d. Shows object in normal position. Figure 2.1-2 Objects with very little thickness require only one view Figure 2.1-3 Two-view drawing Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 10 of 70 calculations Complied by: Kristine M. Capao Revision # 3. Select alternate position for right side view if drawing area is crowded. Figure 2.1-4 Normal location Figure 2.1-5 Alternate location 4. Select view positions to avoid crowding dimensions and notes. Six Principal Views of an Object The simple work piece below shows the six (6) principal sides or views. REAR FRONT BOTTOM Figure 2.1-6 Six principal views of an object Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 11 of 70 calculations Complied by: Kristine M. Capao Revision # An orthographic view is made by projecting the edge of the object perpendicular to a plane of projection. Figure 2.1-7 Plane of projection Plane of Projection Three planes of projection are used in orthographic drawing. These are called the horizontal plane, frontal (vertical) plane, and the profile plane. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 12 of 70 calculations Complied by: Kristine M. Capao Revision # You can use parallel projection technique to create both multiview and pictorial (isometric and oblique) views. 1. In multiview orthographic projection (see details below), the object surface and the projection plane are parallel, and you can see only two dimensions. 2. In isometric view (orthographic) the surface is no longer parallel to the projection plane, but the latter is perpendicular to the lines of sight, with three dimensions being seen. 3. In oblique projection (non-orthographic) the object surface and the projection plane are also parallel, but the lines of sights are not perpendicular to the projection plane, and you can see again three dimensions. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 13 of 70 calculations Complied by: Kristine M. Capao Revision # The planes of projection join and form quadrants. The quadrants are called first angle, second angle, third angle, and fourth angle. The first and the third quadrants are used for drafting purposes. Figure 2.1-8 Quadrants Figure 2.1-9a First-angle projection Figure 2.1-9b Third-angle projection Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 14 of 70 calculations Complied by: Kristine M. Capao Revision # Figure 2.1-9c First- and Third-Angle Projection Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 15 of 70 calculations Complied by: Kristine M. Capao Revision # Principal Dimension of an Object HEIGHT Width - is the perpendicular distance between two profile planes. Height - is the perpendicular distance between two horizontal planes Depth - is the perpendicular distance between two frontal planes. First-Angle Projection (ISO Standard) The first-angle projection is a system of orthographic projection used by the European countries which places the object on the first quadrants. The object is positioned at the front of a vertical plane and top of the horizontal plane. The object is placed between the observer and projection planes. The plane of projection is taken solid in 1st angle projection. Symbol: Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 16 of 70 calculations Complied by: Kristine M. Capao Revision # Here the horizontal plane is below the object. ▪ The top of the object is projected down the horizontal plane. ▪ The rear projects to the frontal plane. Unfolded Planes With the planes unfolded and laid flat, the front view is above the top view. The position of the unfolded planes in the first-angle projection. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 17 of 70 calculations Complied by: Kristine M. Capao Revision # Third-angle Projection (ANSI) The third-angle projection is a system used in the United States which places the object in the third quadrants. The object is placed behind the vertical planes and bottom of the horizontal plane. The projection planes come between the object and observer. The plane of projection is taken as transparent in 3rd angle projection. Symbol: Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 18 of 70 calculations Complied by: Kristine M. Capao Revision # The third-angle projection places the object in the third quadrant. (An observer here would be facing the frontal plane). ▪ Observe that the object is placed below the horizontal plane. ▪ The top view of the object projects up to it, therefore, the top view is in the horizontal plane. ▪ The object is behind the frontal plane. The front view of the object projects forward to it, therefore, the view is on the frontal plane. ▪ The side of the object projects to the profile plane, therefore, the side view will be seen in the profile plane. Unfolded Planes If the planes be unfolded and laid flat, the top view would be above the front view. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 19 of 70 calculations Complied by: Kristine M. Capao Revision # Steps in Projecting the Three Main Views of an Object 1. Study the object. 2. Determine the number of views. 3. Locate the views. 4. Block in the views with light, thin lines using 3H or 4H pencil. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 20 of 70 calculations Complied by: Kristine M. Capao Revision # 5. Lay off the principal measurements. 6. Draw the principal lines. 7. Lay off the measurements for the details (center for arcs, cicles, and triangular ribs). 8. Draw circles and arcs. 9. Draw any additional lines needed to complete the views. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 21 of 70 calculations Complied by: Kristine M. Capao Revision # 10. Darken the lines (visible/object lines using B pencil) where necessary to make them sharp and black and of the proper thickness. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 22 of 70 calculations Complied by: Kristine M. Capao Revision # OPERATION SHEET 2.1-1 Sketch in First Angle Orthographic Projection the following views of the detail shown below. (a) Right side view (b) Front view (c) Top view 1. 2. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 23 of 70 calculations Complied by: Kristine M. Capao Revision # INFORMATION SHEET 2-1.2 Pictorial Drawing Learning Objectives: After reading this INFORMATION SHEET, YOU MUST be able to: 1. Understand the concept and types of pictorial drawings. 2. Analyze how pictorial drawings represent three-dimensional objects. Pictorial Drawing A pictorial drawing shows likeness (shape) of an object as viewed by the observer. It represents a portion of the object and shows the method of its construction. In some presentations, the whole object is shown in one view. Types of Pictorial Drawing: A. Axonometric Pictorial Drawing 1. Isometric Drawing A pictorial drawing showing the three surfaces of the object tilted 30º in front of the observer. s a Angle: a = 30 º, s = 30 º Width: Scale 1:1 Height: Scale 1:1 Depth: Scale 1:1 Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 24 of 70 calculations Complied by: Kristine M. Capao Revision # Isometric drawing according to standard. 2. Dimetric Drawing The angle that is used for the horizontal planes varies according to the angle of view that has been chosen. This type is not widely used. 3. Trimetric Drawing A classification of an axonometric projection where a cube is positioned in the way that no axes and angles are equal when projected to the plane projection. B. Oblique Pictorial Drawing 1. Cavalier drawing – an oblique drawing in which the depth axis lines are full scale or in full size. 2. Cabinet oblique – depth axis lines are drawn one-half scale. 3. General oblique – depth axis lines vary from one-half to full size. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 25 of 70 calculations Complied by: Kristine M. Capao Revision # C. Perspective Pictorial Drawing A. 1-pt. or Parallel perspective A perspective drawing using one vanishing point, the front view is drawn in its true shape in full or scale size. B. 2-pt. or Angular perspective A perspective drawing using two vanishing points. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 26 of 70 calculations Complied by: Kristine M. Capao Revision # C. 3-pt. or Oblique perspective A perspective drawing using three vanishing points. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 27 of 70 calculations Complied by: Kristine M. Capao Revision # Isometric Drawing Axes used in isometric drawing: 1. Vertical axis 2. Right-cross axis 3. Left-cross axis An isometric drawing is a pictorial drawing showing the three surfaces of the object tilted 30 degrees in front of the observer. Isometric lines are lines drawn parallel to the isometric axes. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 28 of 70 calculations Complied by: Kristine M. Capao Revision # Steps in Drawing Isometric from a given Orthographic Views 1. Study the given orthographic views carefully. Estimate the width, height and depth of the object, then sketch the axes used in isometric drawing. 2. Transfer the height (A), the width (B), and the depth (C) of the object to the corresponding axis respectively. Height (A) Width (B) Depth (C) Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 29 of 70 calculations Complied by: Kristine M. Capao Revision # 3. Sketch isometric lines to complete the isometric box. ISOMETRIC BOX 4. Layout details of the object inside the box then finish the pictorial view by drawing the object lines. Isometric view Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 30 of 70 calculations Complied by: Kristine M. Capao Revision # Example Problem: Draw a scaled isometric view from given orthographic views. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 31 of 70 calculations Complied by: Kristine M. Capao Revision # Oblique Drawing A kind of pictorial drawing of an object one surface of which is shown parallel to the frontal plane and the other is inclined to it. Axes in Oblique Drawing Variations in Direction of Receding Axis Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 32 of 70 calculations Complied by: Kristine M. Capao Revision # Classifications of Oblique Pictorial Drawing 1. Cavalier drawing is an oblique drawing in which the depth axis lines are full scale or in full size. The receding lines are true depth – that is makes an angle of 45º and 30º with the plane of projection. 2. Cabinet oblique – Depth axis lines are drawn one-half scale. When the receding line is drawn to half – size, and the projectors make an angle of 30, 45, 60 degrees respectively. 3. General oblique – Depth axis lines vary from one-half to full size. Drawn at any convenient angle and the receding lines are drawn to full size, one third size, one-half size, or one fourth size. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 33 of 70 calculations Complied by: Kristine M. Capao Revision # Procedure in Sketching Oblique Pictorial View 1. Study carefully the given orthographic views. Sketch the vertical line OB and horizontal line OA. B O A 2. Draw line OC as the receding line. B C O A 3. Complete the oblique box by sketching parallel lines to the oblique axes. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 34 of 70 calculations Complied by: Kristine M. Capao Revision # 4. Layout the details of the object inside the oblique box. 5. Erase the unnecessary lines to complete the drawing. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 35 of 70 calculations Complied by: Kristine M. Capao Revision # OPERATION SHEET 2.1-2 Draw an isometric sketch using an isometric box as reference and the given orthographic views. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 36 of 70 calculations Complied by: Kristine M. Capao Revision # INFORMATION SHEET 2-1.3 Dimensioning Learning Objectives: After reading this INFORMATION SHEET, YOU MUST be able to: 1. Identify different types of dimensions used in technical plans. 2. Apply dimensioning standards and techniques. Dimensioning Dimensioning placing sizes and related information on a drawing. Size dimension gives the detail and overall sizes of the object. Location dimension merely locates part or parts and features of the object. Methods of Indicating Dimensions Aligned Method All dimensions are placed aligned with the dimension line and be read from either the bottom or right side of the paper. Unidirectional Method In the unidirectional method, all dimensions are read from the bottom of the page as illustrated. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 37 of 70 calculations Complied by: Kristine M. Capao Revision # Kinds of Dimensions Over-all dimension – every object, regardless of its shape, has three over- all dimensions. An over-all dimension indicates the over-all width, height and depth of an object. Detail dimensions provide size or location information concerning any feature or details of an object other than its over-all dimension. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 38 of 70 calculations Complied by: Kristine M. Capao Revision # Elements of Dimensions Several elements define a dimension in technical or engineering drawings. 1. Dimension — the numerical value that defines the size, shape, location, surface texture, or geometric characteristic of a feature. 2. Basic dimension — a numerical value defining the theoretically exact size, location, or orientation relative to a coordinate system. Basic dimensions are enclosed in a rectangular box & have no tolerance. 3. Reference dimension — a numerical value enclosed in parentheses, provided for information only. 4. Dimension line — a thin, solid line that shows the extent and direction of a dimension. 5. Arrows — symbols at the ends of dimension lines showing the limits of the dimension, leaders, and cutting plane lines. 6. Extension line — a thin, solid line perpendicular to a dimension line, indicating which feature is associated with the dimension. 7. Visible gap — there should be a visible gap of 1 mm between the feature's corners and the end of the extension line. 8. Leader line — a thin, solid line with arrow drawn under an angle & indicating the feature with which a dimension or note is associated. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 39 of 70 calculations Complied by: Kristine M. Capao Revision # 9. Limits of size — the largest acceptable size and the minimum acceptable size of a feature. 10. Plus and minus dimension — the allowable positive and negative variance from the specified dimension. 11. Diameter symbol — a symbol indicating that the dimension shows the diameter of a circle. The symbol used is the Greek letter phi Ø. 12. Radius symbol — a symbol indicating that the dimension shows the radius of a circle. The radius symbol used is the capital letter R. 13. Tolerance — the amount that a particular dimension may vary. Types of Dimensions in Technical Drawing 1. Linear dimension Linear dimension is a type of dimension that can be expressed as any of the following two distances: (A) Horizontal: this distance or measurement is made from left to right (or vice versa) relative to the drawing plane (paper or computer), as shown by the width (the horizontal dimension) in the figure below. Horizontal and vertical distances can be expressed in standard units of linear measurement—mainly in meters, centimeters, millimeters, inches, and feet. (B) Vertical: this distance or measurement is made from up to down (or vice versa) relative to the drawing plane (paper or computer), as shown by depth or height (the vertical dimension) in the figure below. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 40 of 70 calculations Complied by: Kristine M. Capao Revision # 2. Angular dimension Angular dimension is a type of dimension that is indicated either in only degrees or a combination of degrees (°), minutes (′), and seconds (″) which are the units of angular dimension. In any situation(s) where only minutes and seconds are specified, a zero (0) is placed before the number of minutes or seconds, as shown on the last diagram in the figure below—examples of angular units used in angular dimensioning. 3. Diametral dimension Diametral dimension is a type of dimension that expresses the magnitude of the diameter or straight line connecting the centre of a circle with two points on its perimeter. Diametral dimension is used on mostly full circles or arcs whose magnitude is more than half of a full circle. The symbol for diameter is the Greek letter phi Ø. 4. Radial dimension Radial dimension is a type of dimension that expresses the magnitude of the radius or distance between the center of a circle or arc (that is less than half of a circle) and any point on a circle’s or arc’s perimeter. The symbol for radius is the capital letter R as shown in the figure above. 5. Ordinate (or coordinate) dimension Ordinate dimension is the type of dimension that is indicated via rectangular coordinates or rectangular coordinate dimensioning in which a datum line or baseline is established for each Cartesian coordinate and Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 41 of 70 calculations Complied by: Kristine M. Capao Revision # every other dimension is positioned with respect to the datum line or baseline. 6. Reference dimension Reference dimension is the type of dimension that provides extra information that is not essential for fabricating or creating a part or feature. Reference dimension is usually enclosed in parentheses [such as (2.00) as shown in the figure below] on drawings, only providing certain information which cannot be used to fabricate a feature or part. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 42 of 70 calculations Complied by: Kristine M. Capao Revision # 7. Note dimension or Notes Notes are the type of technical drawing dimension described by written specifications or words, more detailed than numerical values and clearly point out specific information and sizes of a feature or features. There are two types of notes: (A) Specific (or local) note: this is the type of dimension that provides information applicable or relevant to specific features and not the whole drawing. Local notes are linked to specific features on drawing views. Three examples of specific notes include: (B) General note: this provides information that is applicable to or relevant to the whole drawing. General notes are linked to all drawing views of a drawing. Three examples of general notes include: (a) FINISH ALL OVER (FAO) (b) ALL DRAFT ANGLES 3° UNLESS OTHERWISE SPECIFIED (c) DIMENSIONS APPLY AFTER PLATING Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 43 of 70 calculations Complied by: Kristine M. Capao Revision # Rules in Dimensioning For a beginner like you, remember these dimensioning rules when placing measurements in your drawing. 1. Each dimension should be given clearly, so that it can be interpreted in only one way. 2. Avoid repetition of dimensions. Dimensions should not be duplicated, or the same information given in two different ways, and no dimensions should be given except those needed toproduce or inspect the part. 3. Use outside dimension if the space is limited and use an inside dimension if there is enough space. 4. The longer dimensions should be placed outside all intermediate or shorter dimensions, so that dimension lines will not cross extension lines. 5. Continuous dimensions should be used whenever possible. 6. Staggered dimensioning should be used when the space for dimensioning is limited. 7. Dimension lines should be spaced uniformly throughout the drawing. 8. When dimensioning a circle, it should be from center to center. 9. Dimension lines should never cross other dimension lines. Dimension lines should not cross extension lines. Dimension lines should be appropriately spaced apart from each other and the view. 10. Dimension figures should be approximately centered between the arrowheads, except that in a “stack” of dimensions, the figures should be “staggered”. 11. Extension lines must have about 10 mm from the object edge and an approximate 2 millimeters after the dimension lines. 12. Extension lines should not touch object lines. 13. Extension line should always leave a visible gap (≈ 1 𝑚𝑚) from a view or center lines before start drawing a line. Extend the lines beyond the (last) dimension line 2-3 mm. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 44 of 70 calculations Complied by: Kristine M. Capao Revision # 14. Extension lines should not cross dimension lines, and they should avoid crossing other extension lines whenever possible. When extension lines cross object lines or other extension lines, they should not be broken. When extension lines cross or are close to arrowheads, they should be broken for the arrowhead. 15. Dimension figures (number) should be lettered with 2H or HB pencil. The height of the figures is suggested to be 2.5-3 mm. Place the figures at about 1 mm above and at the middle of a dimension line. Dimensions figures are entered in millimeters without a neccessity to specify a unit symbol. Angular dimension is expressed in degree with a symbol “ º ” places behind the figure (and if necessary, minutes and seconds may be used together). Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 45 of 70 calculations Complied by: Kristine M. Capao Revision # If there is not enough space for figure or arrows, put it outside either of the extension lines. 16. Notes should always be lettered horizontally on the drawing. 17. Notes should be brief and clear, and the wording should be standard in form. 18. Local notes should be lettered with 2H or HB pencil, lettered horizontally, and with a height of 2.5-3 mm. Must be used in a combination with a leader line. Place near to the feature which they apply but should be placed outside the view. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 46 of 70 calculations Complied by: Kristine M. Capao Revision # Placed above the bent portion of a leader line. 19. Leaders for notes should be straight, not curved. 20. Where space is limited extension lines may be drawn at an angle. 21. Dimensions should be grouped for uniform appearance. Avoid using object lines as extension lines for a dimension. Dimensions must be kept outside the boundaries of views, wherever practical. Good practice Poor practice Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 47 of 70 calculations Complied by: Kristine M. Capao Revision # 22. Dimensions can be placed in series and parallel. When a series of dimensions is applied on a point-to-point basis, it is referred to as chain dimensioning. 23. Avoid dimensioning to hidden features. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 48 of 70 calculations Complied by: Kristine M. Capao Revision # INFORMATION SHEET 2-1.4 Technical Plans, Drawing Symbols and Signs Learning Objectives: After reading this INFORMATION SHEET, YOU MUST be able to: 1. Identify different types of technical plans and their specific applications. 2. Read and interpret various elements of technical plans. Technical Plans A technical plan or working or construction drawing is the general term used for drawings that form part of the production information that is incorporated into tender documentation and then the contract documents for the construction works. This means it has legal significance and form part of the agreement between the employer and the contractor. It is a graphical representation of what will be built, how it will be laid out, the components, framework, and dimensions. There is a construction drawing highlighting the details for every aspect of a construction project. Importance: ▪ The designer can translate the client’s ideas into a definite, practical representation of what he or she wants. ▪ The client can ensure that his or her ideas have been correctly interpreted by the designer. ▪ The contractor can give a firm estimate of what the building will cost. ▪ The designer and sub-contractors know exactly where and how to construct the building. Types 1. Block Plan This drawing gives a layout of the site or the buildings in the surrounding area, laid out on a map drawn to scale. ▪ It gives a firsthand idea of the roads, boundaries and other such details that are necessary to understand where your construction site lies. ▪ It helps the person dealing with your construction plan or project request to understand what and where you are proposing it and help you out with it too. ▪ Block plans are made in relation to Ordnance Survey Maps and the recommended scales used are 1:2500, 1:1250 or 1:500. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 49 of 70 calculations Complied by: Kristine M. Capao Revision # 2. Architectural Drawings Drawing work that is used in building drawings to depict the dimensions, depth, and layout of the actual building, prior to beginning the construction. Architectural Drawings act as a blueprint construction, drawn to scale, to help the engineers visualize the project. Various types of Architectural Drawings commonly used are: Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 50 of 70 calculations Complied by: Kristine M. Capao Revision # ▪ Foundation plan – not to be mistaken for just the ground or basement floor plan. Foundation Plans are drawing work to render any of the floors of the building being constructed. They help visualize the dimension, size, shape, height and configuration of rooms/stairs/landings with each other. ▪ Floor plans – in-depth rendering of the layout of the rooms for each floor. It describes in 2D the orientation of rooms and components to each other. ▪ Sectional Drawings – these are drawings that depict a part or whole of the framework in sliced form. It helps understand the measurements of various building components with each other, the materials used in the construction of those components, the height, depth, and hollowness, etc. ▪ Elevation Drawings – these architectural drawings offer an aesthetic overview of the various components of the building such as columns, windows, and doorframes. It also helps understand the relative surface, internal markings, and relative height of these different components to each other. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 51 of 70 calculations Complied by: Kristine M. Capao Revision # 3. Production Drawings These are used to convey functional information to the workers and engineers on site. It describes the materials, the assembly of various parts, the tools required, the dimensions, and other information required during the process. It may also include additional information or an infographic on how to meet those set requirements. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 52 of 70 calculations Complied by: Kristine M. Capao Revision # 4. Structural Drawings They are useful in understanding the physical, most important aspects of a building framework. They act as a structural design guide for the workers and on-site engineers. Common types of structural drawings are: ▪ Excavation Drawing – this civil engineering drawing describes the dimensions and positions for the excavation process prior to the actual building work. It covers details like tunneling, shafts, removal of soil, grid plans, etc required to start the groundwork. ▪ Column Layouts – These structural drawings include the layouts of the way columns will be laid out. It makes it easier for contractors to plan the layout of the building and start the process by identifying the position and distance between columns across the floor. ▪ Beam Layouts – It includes all the beam-like structures, such as the ones supporting the roof and the windows, or the beams used for strengthening purposes. They are designed for each floor and cover the length, height, material, etc. ▪ Roof slab layouts – this civil engineering drawing describes the exact dimensions of all the slabs required for roofs or slants. It can be designed over AutoCAD software as it requires precision and data. ▪ Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 53 of 70 calculations Complied by: Kristine M. Capao Revision # 5. Electrical Drawings Most residential construction drawings or commercial construction drawings require a functional outline of the number of power outlets, light fixtures, fan fixtures, etc. They also include the wiring pattern and details about the electrical load it can carry. Common details included in Electrical Drawings are: ▪ Earthing layout ▪ Light fixture layout ▪ Generator and other equipment ▪ Cable tray layout ▪ Hazardous area classifications ▪ Lighting protection system 6. Plumbing Drawings Just like electrical layouts, plumbing is another part of any residential or commercial construction drawing that marks the points where plumbing components need to be set up. Plumbing drawings commonly include: ▪ Pipes –water pipes, drainage pipes, internal pipes ▪ Material of pipes ▪ Outlet points – taps, sinks, tanks etc ▪ Position and location of pipes and outlets Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 54 of 70 calculations Complied by: Kristine M. Capao Revision # Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 55 of 70 calculations Complied by: Kristine M. Capao Revision # Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 56 of 70 calculations Complied by: Kristine M. Capao Revision # 7. HVAC These are known as mechanical construction drawings. They provide details and a design framework for heating and ventilation systems in a building. Central heating/cooling, air conditioning vents, ventilators, etc are all included according to the need and site of the building plans. Builders use these design constructs in their process accordingly. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 57 of 70 calculations Complied by: Kristine M. Capao Revision # 8. Firefighting Drawings In today’s construction systems, safety design is paramount. Firefight drawings are also a part of blueprint drawings of a building that allocate points for fire hoses, fire escapes, water outlets, sandbags, or any other fire safety equipment required by the regulatory body overseeing the project. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 58 of 70 calculations Complied by: Kristine M. Capao Revision # 9. Environmental Plans Making sure environmental guidelines and management is properly followed is a part of construction projects that cannot be overlooked. The aim is to minimize environmental damage and future negative impacts of the construction project. It includes measures like: ▪ Chemical disposal mechanisms ▪ Management of erosion and sedimentation ▪ Outlining environmental guideline compliance measures ▪ Measures to handle accidents and emergencies like fire Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 59 of 70 calculations Complied by: Kristine M. Capao Revision # 10. Finished/Interior Drawings These include finer and more detailed plans of the building after the whole structural and architectural framework has been set up. These are required for the aesthetic and functional value of the building. These construction drawings include details of: ▪ Tile patterns ▪ Floor patterns ▪ False ceilings ▪ Paint colors and textures ▪ Plaster ▪ Woodwork ▪ Motifs and designs Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 60 of 70 calculations Complied by: Kristine M. Capao Revision # Meaning of Common Symbols Used on Floor Plans A typical first floor plan Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 61 of 70 calculations Complied by: Kristine M. Capao Revision # A typical second floor plan Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 62 of 70 calculations Complied by: Kristine M. Capao Revision # Abbreviations and Symbols -Some drawings need to convey a lot of information. To avoid confusion and to save space, abbreviation and symbols are used. Abbreviations ABBREVIATIONS | NAME Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 63 of 70 calculations Complied by: Kristine M. Capao Revision # ABBREVIATIONS | NAME Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 64 of 70 calculations Complied by: Kristine M. Capao Revision # ABBREVIATIONS | NAME Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 65 of 70 calculations Complied by: Kristine M. Capao Revision # ABBREVIATIONS | NAME Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 66 of 70 calculations Complied by: Kristine M. Capao Revision # Symbols Indicates a hotplate in the kitchen. Indicates that this is ‘window 8’ Some cross-sectional have a ‘filling’ that symbolises what materials are to be used. In drafting terms, this is called “hatching”. Indicates that it is a concrete member (perhaps a footing) Common Blueprint Symbols Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 67 of 70 calculations Complied by: Kristine M. Capao Revision # Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 68 of 70 calculations Complied by: Kristine M. Capao Revision # Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 69 of 70 calculations Complied by: Kristine M. Capao Revision # References: Technical Drafting Training Regulation Technical Drafting Curriculum Based Curriculum https://www.scribd.com/document/493395893/techdraftmodule8 https://www.splashlearn.com https://www.cuemath.com Manaois, German (2004) Drafting Volume 2. Quezon City, Phoenix Publishing House, Inc., pp 1-22. Document No. Date complied: Perform Issued by: June 2024 mensuration and Page 70 of 70 calculations Complied by: Kristine M. Capao Revision #

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