Module 7 Alphabet of Lines PDF

MODULE 7 ALPHABET OF LINES OBJECTIVES: After reading the topics and doing exercises you will learn to:  define terms used in multi-view projections.  describe various lines included in the alphabet of lines according to weight, construction...

MODULE 7 ALPHABET OF LINES OBJECTIVES: After reading the topics and doing exercises you will learn to:  define terms used in multi-view projections.  describe various lines included in the alphabet of lines according to weight, construction and functions.  apply correctly various lines included in the alphabet of lines in the working drawing.  observe the proper drawing of lines in drawing orthographic projection and pictorial drawings OVERVIEW In technical drawing and computer graphics, a multi-view orthographic projection is an illustration technique in which up to six pictures of an object are produced, with each projection plane parallel to one of the coordinate axes of the object. The views are positioned relative to each other according to either of two schemes: first- angle or third-angle projection. In each, the appearances of views may be thought of as being projected onto planes that form a 6-sided box around the object. Alphabet of Lines (set of conventional line symbols) Various lines are used in drawing orthographic views such as:  Alphabet of Lines Visible/Object Line is a heavy line Hidden Line is medium dashed lines used to represent contour/edges of an equally spaced and used to represent object outlining an area. an edge, corner or feature which is not directly seen in a given surface. Dimension Line composed of thin line Extension/Projection Line very thin with arrowheads at both end and line used to indicate the limit the numerical figure which gives the dimension line. Also used to measurement of the object. transfer/project features or measurements from one view to the other. Long Break Line allows removal of a Short Break Line terminates a view to long central portion of an object to conserve space and avoid congestion. shorten a view. Normally used in pairs. Also separates internal and external features with broken-out sections. Cutting Plane Line shows where the Section Line appears only on a imaginary cutting takes to create a sectional view where the surface has sectional view. May be series of long been cut. Normally drawn 45° dashes, or alternately, two short diagonally. dashes between single long dashes. Arrowheads indicate the direction of sight. Leader Line drawn diagonally, it Reference Line variant of a leader line directs a dimension or note to the area usually with curve portions. where it applies. Normally terminates with arrowheads, but may terminate with a dot. Phantom Line represents the outline Center Line indicates symmetry, of an adjacent position of a given part; center points. Consists of alternate or replaces repetitive detail, such as long and short dashes usually very thin spring coils, gear teeth, threads, etc. line. Drawn with 2 short dashes between single long dashes, but thinner than the cutting/viewing plane line. Chain Line is used to indicate an area Border Line is the heaviest line in or portion of a surface that is to receive drawing used as margin that surrounds special treatment. the entire drawing works. It also suggests completeness.  Directions: Identify the lines used as they were numbered accordingly. Write your answers on the space provided for. 1. _________________________ 7. _________________________ 2. _________________________ 8. _________________________ 3. _________________________ 9. _________________________ 4. _________________________ 10._________________________ 5. _________________________ 11._________________________ 6. _________________________ 12._________________________ NAME________________________________ DATE____________________ COURSE: _________________YR. & SEC.: _______ SCORE: ____________ DRAWING EXERCISE NO. 15 ALPHABET OF LINES Directions: Redraw the given object in a bigger version on the space available. Draw the lines properly, consider the lines according to weight and according to construction.  Rubrics for Drawing Exercises Criteria Excellent Good Fair Poor Accuracy Drawing Drawing Drawing Drawing and exercise is exercise is exercise is exercise is Correctness engagingly somewhat disorganized incomplete and of Work organized and organized, and incomplete not easy to read. (50%) presents complete. at times and is correct and somewhat able complete. to hold the attention of the viewer. Speed The drawing The student The student The drawing (15%) exercise was finished the worked hard and exercise was completed with drawing completed the continued until it minimum effort exercise but it drawing exercise was complete as could have but with a bit the student could been improved more effort it make it; gave it with more might have been effort far beyond effort. outstanding. that required. Neatness Exceptionally Attractive and Acceptably Distractingly (15%) attractive and neat in design attractive but messy or very particularly neat and layout may be messy poorly designed. in design and at times and/or Does not show layout show lack of pride in work. organization Legibility The drawing With a little The student The student (20%) exercise was more effort, the showed average showed average beautiful and work could competence; competence, patiently done; have been adequate, but lack of pride in lettering printed outstanding; not as good as it finished work accordingly. lacks the could have finishing been, a bit touches. careless.  Score Interpretation Description Range (Grade) 91- 100 Outstanding Conditions and provision is excellent and the (1.5 – 1.0) standard of function meets quality. 81 - 90 Very Satisfactory Conditions and provision is extensive and the (2.0 – 1.6) standard of function is above average. 71 – 80 Satisfactory Conditions and provision is adequate and meets the (2.5 – 2.1) normal function. 61 – 70 Moderately Conditions and provision is limited and functions are Satisfactory temporarily acceptable. (3.0 – 2.6) 51 – 60 Needs Conditions and provision needs improvement and Improvement functions are missing. (3.5 – 3.1)