1. EDT 310 - Chapter 41 Review - Linetypes Sacramento City College EDT 310

2. EDT 310 - Chapter 42 Alphabet of Lines u The American Society of Mechanical Engineers (ASME) has developed this standard which is accepted throughout the industry. u The Alphabet of Lines u Reveals shape, size, hidden surfaces, interior detail, alternate positions of parts, etc. u The lines differ in width and character so they are easily distinguishable.

3. EDT 310 - Chapter 43

4. 4 Review of Linetypes u Object lines u Also called “visible lines”. u Show the outline of an object. u Are the most common type of lines used on drawings. u Are medium weight. u AutoCAD calls these lines CONTINUOUS lines.

5. EDT 310 - Chapter 45 Visible Lines

6. EDT 310 - Chapter 46 Review of Linetypes u Hidden Lines u Also called dashed lines. u Show features of an object that are NOT visible in that view. u Are thin lines. u AutoCAD calls this linetype HIDDEN, HIDDEN2, or HIDDENX2.

7. EDT 310 - Chapter 47 Review of Linetypes u Hidden Lines – Spacing and Size u Dashes are 0.125” long, spaced 0.06” apart. u Choose length carefully. If drawing is to be scaled down, dashes may appear too small.

8. EDT 310 - Chapter 48 Hidden Lines u Rules – Hidden Lines u 1. If a hidden line is a continuation of a visible line then a gap is shown. u 2. A gap is also shown when a hidden line crosses but does not intersect another line. u 3. Hidden lines should be omitted when they are not needed for clarity.

9. EDT 310 - Chapter 49 Hidden Lines

10. EDT 310 - Chapter 410 Review of Linetypes u Centerlines u Locate the centers of circles and arcs. u Small dashes cross at the center of a circle. u Center lines should intersect at the short dashes. u Show the axis of a cylindrical or symmetrical shape. u Are thin lines consisting of alternately spaced long and short dashes. u Center lines extend only a short distance past the object.

11. EDT 310 - Chapter 411 Center Lines u Center Lines u Spacing and Size. u Alternating long and short dashes u The long dash (3/4” to 1-1/2”) u The short dash (1/16” to 1/8”) u AutoCAD calls this linetype CENTER, CENTER2, or CENTERX2.

12. EDT 310 - Chapter 412 Center Lines u Additional Rules – Center Lines u 1. Small dashes cross at the center of a circle. u 2. Center lines should intersect at the short dashes. u 3. Center lines should extend only a short distance past the object.

13. EDT 310 - Chapter 413 Center Lines

14. EDT 310 - Chapter 414 Review of Linetypes u Dimension lines u Are thin lines u Are placed between extension lines to indicate a measurement. u Are broken near the center for placement of dimension numeral in mechanical drafting. u Arrows terminate the ends of dimension lines in mechanical drafting. u Are unbroken in architectural drafting. u Slashes or “tic marks” are used in architectural drafting.

15. EDT 310 - Chapter 415 Dimension Lines, Extension Lines and Leaders

16. EDT 310 - Chapter 416 Review of Linetypes u Extension lines u Are thin lines. u Are used to show the “extent” of a dimension. u Begin a small distance from the object and extend 0.125” beyond the last dimension line. u May cross object lines, hidden lines and centerlines. u May not cross dimension lines.

17. EDT 310 - Chapter 417 Review of Linetypes u Extension lines u Centerlines become extension lines when they are used to show the extent of a dimension measured from a circle centerline.

18. EDT 310 - Chapter 418 Dimension Lines, Extension Lines and Leaders

19. EDT 310 - Chapter 419 Review of Linetypes u Leader lines u Are thin lines u Are used to connect a specific note to a feature on a drawing. u Start with a small shoulder at a note. u Terminate with an arrowhead at the feature and has a small shoulder at a note. u The AutoCAD command is LEADER or QLEADER.

20. EDT 310 - Chapter 420 Leader Lines

21. EDT 310 - Chapter 421 Cutting Plane Lines u Cutting plane and viewing plane lines u Are thick lines. u Identify the location of a section.

22. EDT 310 - Chapter 422 Cutting Plane / Viewing Plane Lines u Cutting Plane / Viewing Plane Lines u First Form – (Phantom Line Type) u Alternating long dashes (3/4” to 1 1/2”) and u pairs of short dashes (1/8” with 1/16” space). u Second Form – (Hidden Line Type) u Equal dashes 1/4” in length. u Both forms u Ends bent at 90 degrees and u Terminated by arrowheads to indicate the direction of viewing of the section.

23. EDT 310 - Chapter 423 Cutting Plane Lines

24. EDT 310 - Chapter 424 Viewing Plane Lines u Viewing plane lines are drawn in the same style as cutting plane lines by identify the location of a view.

25. EDT 310 - Chapter 425 Viewing Plane Lines

26. EDT 310 - Chapter 426 Section Lines u Section lines u Are thin lines. u Are drawn in a section to show where material has been cut away.

27. EDT 310 - Chapter 427 Section Lines u Sometimes called “cross-hatching”. u Represent surfaces exposed by a cutting plane passing through an object. u Usually drawn at an angle of 45 o. u Spacing and Size u Space 1/8” dashes about 1/16” apart. u (small drawings - 1/32”; large drawings - 1/8”)

28. EDT 310 - Chapter 428 Section Lines

29. EDT 310 - Chapter 429 Review of Linetypes u Break lines u Are thick lines. u Show where a portion of an object has been removed for clarity or convenience.

30. EDT 310 - Chapter 430 Break Lines u Break lines u Are used to limit a partial view of a broken section. u For short breaks, a thick line is drawn freehand. u Typically used for mechanical drawings. u For long breaks, a long, thin line is drawn with breaks in the line joined by freehand “zig-zags”. u Typically used for architectural drawings.

31. EDT 310 - Chapter 431 Break Lines u Break lines u AutoCAD does NOT produce zig-zag break lines. u They must be drawn manually.

32. EDT 310 - Chapter 432 Break Lines

33. EDT 310 - Chapter 433 Review of Linetypes u Phantom lines u Are thin lines u Are a long dash alternating with two short dashes alternating with long dash. u Phantom lines show: u Alternate positions. u Repeated details. u Paths of motion.

34. EDT 310 - Chapter 434 Phantom Lines u Phantom Lines u Spacing and Size u Thin, long dashes 3/4” to 1-1/2” in length u alternating with pairs of short dashes 1/8” long with 1/16” spacing between the dashes. u AutoCAD calls this linetype PHANTOM, PHANTOM2, or PHANTOMX2.

35. EDT 310 - Chapter 435 Phantom Lines

36. EDT 310 - Chapter 436 Construction Lines u Construction Lines u Very light, gray lines. u Are used to lay out all work. u Light enough so they will not reproduce when making a print. u On drawings for display or photo reproduction, they should not be visible beyond an arm’s length.

37. EDT 310 - Chapter 437 Border Lines u Border lines u Are the “frame” of the drawing. u They should be the heaviest of all lines.

38. EDT 310 - Chapter 438 Drawing Lines with AutoCAD The LINE Command

39. EDT 310 - Chapter 439 Drawing Lines u AutoCAD draws individual line segments between two points on the screen.

40. EDT 310 - Chapter 440 The LINE Command u To draw lines with AutoCAD u Type “L” or “LINE” at the Command: prompt. u Or u Pick the LINE button from the Draw Toobar u Or u Pick LINE in the Draw Pull-Down Menu

41. EDT 310 - Chapter 441 The LINE Command u When you use LINE, u A prompt asks you to pick a starting point. u Select a first point with your left mouse button. u Select a second point with your left mouse button. u Select a third point with your left mouse button.

42. EDT 310 - Chapter 442 The LINE Command u A line can be “closed” by typing “C”. u Closing a line draws a line from the last picked point to the starting point.

43. EDT 310 - Chapter 443 Setting the Linetype Scale

44. EDT 310 - Chapter 444 Setting the Linetype Scale u The linetype scale sets the length of dashes and spaces in linetypes. u When you start AutoCAD u The global linetype scale is automatically set to match the units you select. u The global linetype scale can be overridden at the object level. u THIS IS NOT RECOMMENDED !

45. EDT 310 - Chapter 445 Setting the Linetype Scale u The default object linetype scale factor is 1.0. u Changes to the default linetype scale are made to make your drawing more closely match standard drafting practice.

46. EDT 310 - Chapter 446 Setting the Linetype Scale u A value of less than 1.0 u Makes the dashes and spaces smaller. u A value greater than 1.0 u Makes the dashes and spaces larger.

47. EDT 310 - Chapter 447 Setting the Linetype Scale u Experiment with the different linetype scales until you achieve the desired results. u ALWAYS try to set linetype scale variables at the GLOBAL level first! u You may need to adjust one or two lines, but DO NOT TRY TO ADJUST ALL INDIVIDUAL LINE TYPE VARIABLES!

48. EDT 310 - Chapter 448 Setting the Linetype Scale u The Properties window lists a linetype scale property. u Change the value of individual object linetypes with this box.

49. EDT 310 - Chapter 449 The LTSCALE Variable

50. EDT 310 - Chapter 450 The LTSCALE Variable u The LTSCALE variable u Affects the entire drawing. u The default value is 1.0. u The drawing REGENERATES after changing the LTSCALE variable.

51. EDT 310 - Chapter 451

52. EDT 310 - Chapter 452 Coordinate Systems Cartesian, Relative and Polar

53. EDT 310 - Chapter 453 Point Entry Mode u Each of the point entry methods uses the Cartesian coordinate system. u The Cartesian coordinate system is based on selecting distances from three intersecting axes, X, Y, and Z. u A location is defined by its distance in x,y from the origin point. u Most of our work will be in 2D not 3D.

54. EDT 310 - Chapter 454 The Cartesian Coordinate System u The Origin divides the coordinate system into four quadrants. u Points are located in relation to the origin. u The Origin is point 0,0 and is the location where the X and Y axes cross. u For AutoCAD, the origin is the lower-left of your drawing.

55. EDT 310 - Chapter 455 Origin (0,0) Quadrant 1

56. EDT 310 - Chapter 456 The Cartesian Coordinate System Quadrant #1 +x, +y Quadrant #3 -x, -y Quadrant #2 -x, +y Quadrant #4 +x, -y Origin (0,0)

57. EDT 310 - Chapter 457 Using Absolute Coordinates u Points are measured from the origin. u A point [4,2] is u 4 units in the X direction. u 2 units in the Y direction. u from the origin. u The coordinate display on the lower left corner of the screen shows the location of the cursor at any time.

58. EDT 310 - Chapter 458 Using Absolute Coordinates u You can draw lines by typing in the coordinates of the line. u Command: L or LINE u Specify first point: 4,2 u Specify next point or [Undo]: 7,2 u Specify next point or [Undo]: 7,6 u Specify next point or [Undo]: 4,6 u Specify next point or [Undo]: 4,2 u Specify next point or [Undo]: [Enter] u Command:

59. EDT 310 - Chapter 459 Using Relative Coordinates u Relative coordinates are located from the previous position, rather than from the origin. u The “@” symbol must precede each entry.

60. EDT 310 - Chapter 460 Using Relative Coordinates u Command: u Specify first point: 2,2 u Specify next point or [Undo]: @6,0 u Specify next point or [Undo]: @2,2 u Specify next point or [Undo]: @0,3 u Specify next point or [Undo]: @-2,2 u Specify next point or [Undo]: @-6,0 u Specify next point or [Undo]: [Enter] u Command:

61. EDT 310 - Chapter 461 Using Polar Coordinates u A point located using polar coordinates is based on u the distance from a fixed point (@6 u at a given angle (< 45) u Procedure: u Enter the distance u then u Enter the angle u Example: @6<45

62. EDT 310 - Chapter 462 Using Polar Coordinates u The angular values used for polar coordinates are: u 0 = east (or to the right) u 90 = North (or up) u 180 = West (or to the left) u 270 = South (or down).

63. EDT 310 - Chapter 463 Using Polar Coordinates u @4<45 means u Measure from the previous point u A distance of 4 u At an angle of 45 degrees from 0 degrees.

64. EDT 310 - Chapter 464 The Coordinate Display

65. EDT 310 - Chapter 465 The Coordinate Display u The coordinate display shows the current cursor location. u Turn the cursor tracking display on and off with the [F6] key.

66. EDT 310 - Chapter 466 The COORDS Variable u The COORDS variable lets you choose how the coordinates will be displayed. u 0 = the coordinate display is static. Coordinates are displayed only when points are selected. u 1 = the coordinate display is dynamic. u 2 = the coordinate display is in polar mode showing length at an angle.