1 / 50

# Engineering Graphics

Engineering Graphics. A few highlights. See “A Brief Introduction to Engineering Graphics” in the Resources section of the ME2011 web site See Q01 on the Assignments page for what you need to know for the graphics quiz. Documenting a part requires. 1. SHAPE 2. SIZE 3. MATERIAL 4. TOLERANCE

## Engineering Graphics

E N D

### Presentation Transcript

1. Engineering Graphics A few highlights

2. See “A Brief Introduction to Engineering Graphics” in the Resources section of the ME2011 web siteSee Q01 on the Assignments page for what you need to know for the graphics quiz

3. Documenting a part requires... 1. SHAPE 2. SIZE 3. MATERIAL 4. TOLERANCE 5. FINISH

4. Top Right Front Multiview drawings TOP RIGHT SIDE FRONT “3rd angle projection”

5. Six Principle views: obey layout

6. Basic lines (the “alphabet of lines”) Object line Hidden line Center line Dimension line

7. FRONT FIND THE MISTAKES!

8. CORRECT DRAWING

9. Interpreting Center Lines Enough Info? Enough Info?

10. COULD BE THIS...

11. OR THIS Centerlines imply symmetry, NOT revolution per se

12. HERE, ONLY 2 VIEWS NEEDED (Correct drawing)

13. Find The Mistakes!

14. Find The Mistakes!

15. A A SECTIONS YES NO

16. DIMENSIONING 1. SHAPE2. SIZE3. MATERIAL4. TOLERANCE AND FINISH

17. 5 5 3 3 2 3 5 5 Dimensioning rules: …find the mistakes.

18. 6.0 6.0 Design Detail½” thick aluminum block Which is more expensive: A or B and why? A B 4.0 4.1 What if A was 3.9 in width?

19. www.mcmaster.com

20. 6 6 2 4 2 2 6 6 Dimensioning Choices& Design Intent If change width of block to 8, what happens to the hole location? B A

21. Example

22. TOLERANCES www.efunda.com/processes/machining/drill.cfm www.efunda.com/processes/machining/drill_press.cfm

23. ½ inch drill bit: +/- .0040 ½ inch reamer: +.0003, -.0000

24. Representing tolerances

25. Tolerance stack-up What is min and max height of stack? 14.7515.25 ? 3.0 ± .05 5 high stack

26. Tolerance Stacking Ans: +/- 0.3 What’s the tolerance (+/-) on dimension x?

27. .626 .623 .625 .622 • Will all shafts fit into all holes? • A = yes, B = no • What is maximum clearance? • A = .001, B = .002, C = .003, D = .004 Holes and shafts hole shaft .623 .622 .626 .625

28. { A 0.030 + B 0.003 4.0 - Design Detail Bent aluminum sheet, 1/16” thick A or B: Which is more expensive and why?

29. Geometric Dimensioning and Tolerancing (GD&T)

30. 1.000 ±.005 3.000 ±.005 ? ? Traditional tolerancing is ambiguous

31. .25 ± .01 .25 ± .01 + + Ambiguity… Square deviation Circular deviation

32. .25 .125 +/- .002 .01 Geometric Dimensioning and Tolerancing • Ideal position of hole. .25, is marked with boxand no +/- notation. • Feature control box shows how close hole is to exact; within circular tolerance zone with diameter .01

33. Threaded Fasteners What they are and how to indicate on a drawing

35. Head shapes Cap screw Socket head cap screw (SHCS)Set screw Pan Flat Round

36. Slotted Phillips Torx Driving a fastener Hex cap Hex head (Allen head)

37. www.mcmaster.com ¼-20, RHMS, slotted, steel

38. Name the Fastener:

39. Name the Fastener: Socket Head Cap Screw Socket Head Cap Screw with counterbore

40. Phillips Flat Head Screw with countersink

41. O .166 . 75 Holes 19 DRILL – 0.75 DEEP or DEPTH0.75 REF Pix from www.mcmaster.comunless noted

42. Convention for threaded holes 6-32 THRU TOP FRONT FRONTSECTION

43. .4219 1.501/2 – 13 1.325 Blind threaded holes 1/2 – 13 x 1.325 DEEP THREAD DEPTH DRILL DEPTH

44. .562 – 82O CSK, 1.125 .562 1.125 x 82O Countersunk holes

45. 19 29 14 Counterbored holes 19 DRILL – 29 CBORE, 14 DEEP C-BORE DEPTH

More Related