MD 121 Machine Construction Saturdays, 10:00 am– 12:00 am @ Room 420 Instructors: Office Hours: Tel: e-mail: Dr. Khaled Ahmed, Assistant Professor Dr. Wael Khair, Assistant Professor Saturdays 2-3; 1058; dr.kh.ahmed@gmail.com Textbook and Reference Materials: K.L. Narayana, P. Kannaiah, and K. Venkata Reddy, "Machine Drawing", Third Edition, NEW AGE INTERNATIONAL (P) Ltd., New Delhi - 110002, 2006. K. Venkata Reddy, “Text Book of Engineering Drawing", Second edition, BS Publications, Hyderabad - 500 095 - A.P, 2008. Colin H Simmons, and Dennis E Maguire, "Manual of Engineering Drawing", Second edition, Elsevier Newnes, Burlington MA 01803, 2004. Class notes handouts Intended Learning Outcomes (ILO’s) Knowledge and Understanding: You will learn how to; Understand the basic methods for machine assembly Distinguish between the data and instructions used for both working and assembly drawings Professionally deduce and sketches both working and assembly drawings according to the international standards Intellectual You will learn how to; Motivate your intellectual abilities to imagine and deduce machine parts and a whole machine from the drawings views. Motivate your imagination for producing new ideas and methods in machine drawings. Create new concepts for the design of machine components and also for assembly of them. Professional Skills You will learn how to; Practice the standard drawing methods to generate both working and assembly mechanical drawings. Write and specify correctly and according to standards the instructions and machining marks and the dimensions on mechanical drawings. General You will learn how to; Cooperate to work in groups through small scale projects Work coherently and successfully as a part of a team. Course Outline Topic Weeks 1. Revision Chapters (1-4) 1 2. Reading A Drawing Chapter (17) 1 3. Free Hand Sketching Chapter (13) 1 4. Assembly Drawings Chapter (18) 1 5. Fits and Dimensional Tolerances Chapter (15) 1 6. Geometrical Tolerances Chapter (20) 2 7. Engineering Materials Collections 1 8. Working Drawings Chapter (19-20) 1 9. Mechanical Joints (1- Threaded Joints) Chapter (5) 3 10. Machine Parts Collections 2 Total 14 Problems Sheets will be handed in the class after discussed in the lecture An extra class will be given to students with Mark “C” every next Saturday A term project will be given by Dr. Wael and will be submitted at the end of the term Course Assessment and Evaluation We shouldn’t learn to get marks We shouldn’t learn to get certificates We shouldn’t learn to get titles Why do we learn? To gain knowledge To achieve objectives To build career Why do we need assessment and evaluation? To measure the achieved objectives To point out what in need for improvements Class Work …………………………………………………….. 10% Extra Class Work (Mark “C” students will get bonus) …….. 10% Course Project ………………….……………………………… 10% Lecture Quizzes ……………..………………………………… 5% Mid Term (November 27th 2010)…………………………… Final Exam (Sit in Exam)……………………………………… 10% 65% Revision How to Keep Your Drawing Clean Do Don’t Drawing Sheet Size Assembly Drawing Working Drawing Types of lines and their applications Types of lines and their applications Types of lines and their applications PROJECTION SYSTEMS PROJECTION SYSTEMS 1. First angle system - European country - ISO standard First Quadrant 2. Third angle system - Canada, USA, Japan, Thailand Third Quadrant ORTHOGRAPHIC PROJECTION 1st angle system 3rd angle system ORTHOGRAPHIC VIEWS 3rd angle system 1st angle system Folding line Folding line Folding line Folding line ORTHOGRAPHIC VIEWS 1st angle system Right Side View Front View Top View 3rd angle system Top View Front View Right Side View PROJECTION SYMBOLS First angle system Third angle system Quick Quiz 3. Which is in correct first angle projection ? (180 sec) a) b) c) d) 0 45 90 135 180 4. Which is in correct third angle projection ? (180 sec) a) b) c) d) 0 45 90 135 180 5. Which is a wrong 3rd angle orthographic views ? (180 sec) a) b) c) d) 0 45 90 135 180 VIEW SELECTION STEPS 1. Orient the object to the best position relative to a glass box. 2. Select the front view. 3. Select adjacent views. STEP 1 : Orient the Object The object should be placed in its natural position. The object should presents its features in actual size and shape in orthographic views. GOOD NO ! STEP 2 : Select a Front View The object’s longest dimension should be presented as a width. First choice Second choice Waste more space Inappropriate GOOD STEP 2 : Select a Front View The adjacent views that are projected from the selected front view should appear in its natural position. Inappropriate STEP 2 : Select a Front View Choose the view that have the fewest number of hidden lines. GOOD Inappropriate STEP 3 : Select an Adjacent View Choose the view that have the fewest number of hidden lines. GOOD Inappropriate GOOD Inappropriate STEP 3 : Select an Adjacent View Choose the minimum number of views that can represent the major features of the object. Necessary Hole’s location can be specified on the same view. Easy to understand Difficult to interprete. Necessary STEP 3 : Select an Adjacent View Choose the views that are suitable to a drawing space. POOR Not enough space for dimensioning. STEP 3 : Select an Adjacent View Choose the views that are suitable to a drawing space. GOOD D Example : View selection H mislead to… W F.V. D H W F.V. & T.V. Size description Shape description Three views F.V. & R.S.V. ONE-VIEW DRAWING Flat part having a uniform thickness. 1 Thick Unnecessary These 2 views provide only information about the part thickness ! ONE-VIEW DRAWING Cylindrical-shaped part. Unnecessary Repeat ! Infer from CL Unnecessary TWO-VIEW DRAWING There exists an identical view. Repeat ! Unnecessary TWO-VIEW DRAWING The 3rd view has no significant contours of the object. Unnecessary TWO-VIEW DRAWING The 3rd view has no significant contours of the object. Unnecessary Quick Quiz 1. Which should be the natural position of the light bulb ? (20 sec) a b) c) d) 0 5 10 15 20 2. Which are the necessary views ? (60 sec) a) A-C-E E D b) E-B-D B c) E-A d) E-C A 0 15 30 45 60 C F Projection Projection Projection Quick Quiz Projection B(FV) B(SV) A(TV) D(FV) C(SV) A(FV) C(FV) D(SV) Drawing Reading Drawing Reading Rear tool post is generally used on capstan lathes, mainly for parting-off operations. It is fixed on the cross-slide in the slots, provided at the rear side of the lathe