2 Learning ObjectivesList and recognize by name; symbol; and ANSI number these materials:- Cast Iron Aluminum Brass, Bronze,- Steel Zinc or CopperIdentify a drawing as being a:- Full Section Offset Section Revolved Section- Half Section Broken-Out Section - Removed SectionGiven an orthographic view; draw section views:- In Pencil or In AutoCADUse revolutions and partial views (as conventional practices) to construct sectional views of an object.List the parts of a drawing which do not get crosshatched, even if the cutting plane passes through them.Sketch a cutting plane for any of the sections listed above
3 Readiness Assessment Test 9.2.1 Individually answer the following questions. You will be given 2 minutes:
4 Readiness Assessment Test 9.2.1 Individually answer the following questions. You will be given 2 minutes:List 4 types of sectional views.
5 Team Discussion Item As a team, discussing the following question: What is the purpose of sectional views?
6 Purpose of Sections Show internal detail Replace complex orthographic viewsDescribe materials in an assemblyDepict assembly of parts
7 Sectioning Practices Different parts at different angles Hatch spacing of about 1/16”-1/8”Cutting plane line .020” wide (bold)Section or hatch lines -- thin .007”Visible lines -- wide .015”Not parallel or perpendicular to boundary
8 Sectioning PracticesWhen sectioning an assembly of several parts, draw section lines at varying angles to distinguish separate parts.
9 Most common ANSI Material Patterns ANSI No Name PatternANSI Cast Iron, GeneralANSI SteelANSI Brass, Bronze, CopperANSI Magnesium, AluminumEarth
12 Cutting PlaneCUTTING PLANE LINEThe sight arrows at the end of the cutting plane are always perpendicular to the cutting plane.Line thickness of the cutting plane is the same as the visible object line.The direction of the arrow indicates the line of sight.
13 Types of Sections……..Fig #: Broken-out section……………6.3Conventional breaks………….6.4Full section……………………..6.5Half section……………………..6.8Revolved section……………..6.10Removed section……………..6.11Offset section………………(See Essentials of Engineering Design Graphics by Vinson for figure references)
14 Full Section Cutting plane passes through entire object Hidden lines are omittedVisible lines “behind” the cutting plane must be shown
15 Individual Exercise (7 min) ● Sketch a full section of the object shown below
16 Individual Exercise (7 min) ● Were you correct Individual Exercise (7 min) ● Were you correct ? ● What material (hatch pattern) did you use?
17 Half section: A quarter of assembly removed CUTTING PLANE LINEA quarter of assembly removedHalf of view is cross-hatchedALL hidden lines may be omittedCenter line divides halvesCenter line remains only if associated feature is sectioned
18 Offset section: Bend the cutting plane to show more features CUTTING PLANE LINEBend the cutting plane to show more features
19 Offset section: Sectional view does not denote location of offset CUTTING PLANE LINESectional view does not denote location of offset
20 Revolved section: Show cross- sections by rotating sections 90o The section view stays on the object.
21 Removed section:Removed sections are offset from the object.
22 Broken out section: Used to section a small portion of the object Does not modify the rest of the view
23 Conventional Practices Conventional practices are accepted drawing techniques that violate the rules of orthographic projectionThey are designed to simplify orthographic drawing of complex features.
26 Parts Not Sectioned.Don’t crosshatch (even though the cutting plane may pass thru them):Ribs, webs, spokesThin parts like gasketsBall bearings, roller bearingsMost vendor items: Bolts Washers Shafts Nuts Screws Pins
27 Partial Views Use partial views to conserve space Which half depends on whether you section the view or not.
28 Conventional breaks: …….For extremely large parts
29 Crosshatching in AutoCAD AutoCAD can apply a given pattern to fill an areaThe area must be a closed areaTo fill the area use the BHATCH command.
30 Pair Homework Assignment Drawings (in AutoCAD):28 all29 all32 a, b, c34 allDue: Beginning of class 10.2