Bruce Mayer, PE Licensed Electrical & Mechanical Engineer BMayer@ChabotCollege

1. Engineering 22 OrthroGraphicView Dwgs-2 Bruce Mayer, PE Licensed Electrical & Mechanical EngineerBMayer@ChabotCollege.edu

2. Learning Goals • How to Unfold the “Glass” Box to draw Perpendicular (OrthoGraphic) Projection Views • Determine the Minimum No. of Views Needed to Fully Describe an Object • Properly Place Views Relative to Each Other • Which Views show Which Combination of the Object’s H, W, & D

3. Learning Goals cont • Understand the Criteria for Selecting the CENTRAL View • Apply the Guidelines for the Proper Use of Hidden Lines • Determine When Lines/Shapes are in TRUE Length/Shape as opposed to FOREShortened • Construct MultiView Orthographic Projection Drawings

4. Unfolding The Glass Box • Hinge the Four Intersections on The Frontal Plane And “Flatten Out” the Box • Maintains theTRUE-LengthOf Lines Parallelto the Viewing Planes • The 5 Hinge Lines are Known as FOLDING Lines

5. Steps to MultiView Drawing • Select Minimum No. of Views • Usually 2-4 • Could be ONE, could be 6+ • Block-In View-Envelopes, and Properly Arrange the Needed views • “Grid” Views to Reveal Vertex Points • Note that Some Views Share Common dims • e.g., Front & Top share Width

6. Steps to MultiView Drawing cont • Use XLINE & OFFSET Commands From Envelope-Box Edges to Locate Vertices • Use “Miter-Line” to Xfer Depth-Dims Between Top/Bot and Rt/Lt View • Connect the Grid Vertices with the Appropriate Line Type • Remove all Unneeded Grid and Construction Lines • TurnOff & Freeze Layers can help

7. MultiView Steps Summarized • Pick Views • Block It • Grid It • Connect the Dots • Clean Up • Done

8. Miter Line 1 2 4 3 A 4,1 3,2 2,1 3,4 Surface Type A:Principal Surface • True size in one view • Edge (line) in other 2 views • Plane → Line in Two views • Ordering convention When vertices overlap in a view • X,Y : First number (X) corresponds to the vertex that is in front of and overlaps with the vertex corresponding to the second number (Y).

9. 1 2 4 3 B 4,1 1 4 2 3,2 3 Surface Type B:Inclined Surface • Characteristic shape in 2 views but NOT true size in either • Edge (line) Seen in 3rd view • Lengths of sides can be determined from appropriate views

10. 2 1 3 C 2 1 1 2 3 3 Surface Type C:Oblique Surface • Characteristic shape in all 3 views but true size in none Q: In which views could you get the true length of edges of this oblique surface? 1 to 2 1 to 3 3 to 2 Top Front Side

11. Oblique Surfaces Example • Make a MultiView OrthoGraphic Projection Drawing of this shape Time For Live Demo

12. Measure Object 2x2x1H 8 TView → 8D x 16W 4 Ø2 x 6L 4 5 2 2x2 Chamf2PL. 16 2H FView → 5H x 16W RView → 5H x 8D

13. Oblique Surfaces Final Result

14. ID the Oblique Surfaces

15. Ellipses in OrthoGraphic • If the Hole Axis is Perpendicular to the Projection plane, then the Hole appears in TRUE Shape and it’s Diameter can be Transferred or Measured • Any ROUND hole that is NOT Parallel to the Projection Plane will Appear as an Ellipse in that View • If we can find the Major & Minor Axis Distances ACAD can Make the Ellipse

16. Holes in Slanted-Surfaces Demo • Make 3-View Dwg of this Object • Expect Ellipses in • Top View • Rt-Side View • “Exit” Surfaces

17. Determine Bounding-Box Sizes • Block-In sizes • FView → 2.8W x 2.44H • TView → 2.8W x 2.8D • RSView → 2.44H x 2.8D

18. All Done for Today Ellipses arePAINFUL To Draw By Hand

19. Engr/Math/Physics 25 Appendix  Time For Live Demo Bruce Mayer, PE Licensed Electrical & Mechanical EngineerBMayer@ChabotCollege.edu

20. Oblique Surfaces Example 2x2x1H 8 TView → 8D x 16W 4 Ø2 x 6L 4 5 2 2x2 Chamf2PL. 16 2H FView → 5H x 16W RView → 5H x 8D

21. 1. Block In 3 Views • Front View is taken from the most NATURAL position • Extensive use of Offset Command • Build Side Box with Mitre Line

22. 2. Grid the Boxes • Extensive use of Offset-Command and Mitre-line

23. 3. Build Slot and More Gridding • Use: Osnap, CIRCLE (dia.), LINE (tan), OffSet

24. 4. Trim Out Front View • Use: Osnap, Fillet, Trim, Line (OBJ and HIDDEN Layers)

25. 5. Complete Front View • Use: Osnap, Trim, MatchProp • Use Offset to add CenterLines

26. 6. Trim Out Top View • Use: Osnap, Fillet, Trim, Line (OBJ Layers), MatchProp

27. 7. Complete Top Vew • Use: Osnap, Erase, Dimension → Center Mark, Line (Center Layer) to Connect Slot Center

28. 8. Trim Out Rt-Side View • Use: Osnap, Erase, Line (OBJ Layer), Copy (HL’s, CL’s), Grid on Mitre for Notch-HLs

29. 9. Complete Rt-Side View • Use: Xline, Offest, Osnap, Erase, Trim, MatchProp, New Layer

30. Holes in Slanted Surfaces • Block-In sizes • FView → 2.8W x 2.44H • TView → 2.8W x 2.8D • RView → 2.44H x 2.8D

31. 1. Block In 3 Views • Extensive use of Offset Command • Build Side Box with Mitre Line

32. 2. Grid the Boxes • Extensive use of Offset Command • Use Line command with Relative CoOrds • @L<θ (@ length, Angle-Theta) • Move Construction Circle Along Slanted Line to locate Hole Ctr

33. 3. Trim Out Front View • Extensive use of Trim and Erase Commands

34. 4. Start Slant Hole • Trim Out Partially Top & Side Views • In FView Use Copy to make Slant line Parallel to Slant Surface-A • Use Line (per) and Offeset to Build edges of Slant Hole • Project Slant Hole Edges UP & RT

35. 5. ID Ellipse Axes • In FView Make Hidden and Center Lines for Slant Hole • Use: Trim, Chg-Layer, Offset, Extend • ID Major and Minor Axes in Top & Side Views • Hole-Ø shows in TL in the DEPTh Direction → Major • Hole-Ø ForeShortened in Width & Height

36. 6. Draw Ellipses in 2 Views • Use Draw-Ellipse → Axes, End • Trim-Out T & RS Views

37. 7. Trim Out Top & Side Views • Trim-Out T & RS Views • Now the HARD Part → Constructing HIDDEN Line Ellipses associated with the Slant Hole Exiting Surfaces • BOTTOM • LEFT SIDE

38. 8. Exit-Ell Construction Lns • ID Exit Points in the FView and Extend Construction Lines Up & Rt • To Find Ellipse CENTER on LSide Need to EXTEND the Vertical Surface

39. 9. Add Construction Ellipses • Draw In Ellipses using the • Previously ID’d Centers • Previously ID’d Axis End-Pts • 1.5” Dia as the other Axis Dim

40. 10. Trim Out Ellipse • Trim Ellipses at the Bottom and Left-Side Surfaces • Trim Ellipse–Tangent lines at the appropriate points (see Dwg) • Place Trimmed Ellipses and Ellipse-Tan Lines onto HIDDEN Layer • Construct previously missed Hidden Line

41. 10. CleanUp → Done • Most Difficult Construction → Flat-Surface-Exit Ellipses

42. Hidden Line Example 2 • Block-In sizes • FView → 15W x 7H • TView → 15W x 6D • RView → 7H x 6D 6 11 2 Ø2 3 3 4 4 3 3 4 3 8 1Hx2D Groove, Ctr’d 11