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Engineering 22. Working Drawings-2. Bruce Mayer, PE Licensed Electrical & Mechanical Engineer BMayer@ChabotCollege.edu. Standard Borders. Almost All Engineering Firms Have Some Standard/Default Elements That are Included in all Engineering Drawings
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Engineering 22 WorkingDrawings-2 Bruce Mayer, PE Licensed Electrical & Mechanical EngineerBMayer@ChabotCollege.edu
Standard Borders • Almost All Engineering Firms Have Some Standard/Default Elements That are Included in all Engineering Drawings • These Elements are incorporated into Standard “Borders & Title-Blocks” • When you First Go to Work for a Design Firm find the standard “Border” or “Frame” and make sure you understand the meanings of the all the elements
Example of Std Border RememberThis?
Anatomy of a Working Dwg Rev. Block Zone No. Note Block Zone Ltr. Note Indicator BoM BallTag On-Dwg BoM Title Block FOIA Disclaimer
Anatomy of a Working Dwg Zone Block Section/View Line Separate-SheetParts List Detail Bubble
Anatomy of a Title Block • Drawing Title Block • Drawing Number • Release Block • Revision Level • Tolerance Block • Dwg Sheet Size • Dwg Scale • Matl-Spec Block • BoM Table Headings • Dwg Sheet: No. & Cnt • Company ID Block • Co. Division ID
Zoning & Reving Zone 7B (or B7)
Notes & Comments - 1 • Revisions Must be Carefully Documented; Especially if they affect • Form (physical Shape) • Fit (mounting, or interface locations) • Function (how it works) • Zoning on Sections & Details is Optional for 1 or 2 sheet drawings • Rev’s should be Zoned UnLess meaning is “obvious”
Notes & Comments - 2 • Show Parts & Assemblies in their most “Natural” Position as implied by function or Mounting • Part Number Formats Vary Widely • Watkins-Johnson Co. → • 967852 or 984377-003 • Olympus Japan → SS0251E0 • Dawn VME → 11-1011310-12
Drawing SCALE Interpretation • Typical Scale CallOut SCALE 1:16 Length On DRAWING Length in REAL WORLD • Example: Length In REAL WORLD = 73.75”
Architect/CE Scale Example • Recall Scale Definition Size on DRAWING Size in REAL WORLD • Example - Given Scale: 2” = 1’-0” • Drawing Size → Scaling UP Find
mm Scale Example • A Scale DOWN Example • Given Scale: 1mm = 30mm • Use TAPE MEASURE to Determine Real World Size = 6810 mm (22.34 ft) • Calculate Length of this Line on DWG
Length On DRAWING Length in REAL WORLD Drawing SCALE Alternative • Some Other Common Scale CallOuts SCALE 1=10 or SCALE 1/4 • Watkins-Johnson • Olympus
Using The Drawing Frame • The Chabot Engineering Drawing Frame Should be used for Formal Engineering Drawings • The FRAME should be SCALED Up or Down to fit the FULL SCALE Object • i.e., the OBJECT is Drawn at 1:1, then the Frame-Border is adjusted to fit Time For Live Demo
1st vs. 3rd Angle Projection Lside V Front V Top V Projection Box 1st Ang Proj 1st-Ang. Note Front Surface is Projected BACKWARDS Frontal PlnFront V. Profile PlnLside V. 3rd AngleUSA, Asia Horizontal PlnTop V. Profile PlnLside V. Frontal PlnFront V. 1st Angle (Europe) Horizontal PlnTop V.
1St Angle Projection • The USA Conventionally Uses the So-Called “THIRD” Angle Projection Produced by Unfolding the “Glass Box” • The European “FIRST” Angle Convention Essentially Projects the SHADOW of An Object Projected Onto a Screen BEHIND it. • The 3rd Angle (USA type) Technique is Much More Intuititive
1st Angle Projection • Note • Rearward Projectors • “Opposite” Positioning of the Views
Who’s on First, I-Don’t-Know’s On Third (c.f. Abott & Costello) THIRD Angle Proj FIRST Angle Proj “Third Angle Projection” Symbol Appears in Almost all Dwg Title Blocks
1st & 3rd Angles Summarized • In FIRST-ANGLE projection, each view of the object is projected in the direction (sense) of sight of the object, onto the interior walls of the box • In THIRD-ANGLE projection, each view of the object is projected opposite to the direction (sense) of sight, onto the (transparent) exterior walls of the box
All Done for Today ProjectionQuadrantsReVealed
Engr/Math/Physics 25 Appendix Time For Live Demo Bruce Mayer, PE Licensed Electrical & Mechanical EngineerBMayer@ChabotCollege.edu
Open Title Block Chabot_TitleBlock_D_BMayer_050909.DWG Save Std Border as 987654-321_Weld_Assy.DWG Open Design File Example_Insert_into_Dwg-Border_90661201.DWG Zoom Out 0.3x Make Rectangle around object EyeBall to see if HEIGHT or WIDTH will be Frame Scaling Factor Choose WIDTH Use DIST to Measure Rectangle Width at ≈ 91.5 Using Std Frame Demo - 1
Zoom in On Border Erase the Unneeded Objects & Notes Leaves Clean Border Template Measure “Working (open) Width” of Border at ≈32 Calc ScaleUp MIN Factor at 91.5/32 =2.86 Allow 10% on Each side for Working ScaleUp Factor 2.86*1.2 = 3.43 Use 3.5 Using Std Frame Demo - 2
ScaleUp Border by 3.5x using Bot-Rt pt with NODE opt Move Rect & WeldFrame Block-Contents to Expanded Border Erase Rectangle Enter Object BoM into Frame Bom Note that Obj BoM is NOT Scaled Same as Broder This is a Good Reason for Putting BoM separate Sht Copy (type) 4 items from Ylw BoM into Border BoM Copy at least one BoM Line Using Std Frame Demo - 3
Fill In Title Block Using Double-Click to Activate AttEdit p/n = 987654-321 Scale: 1 = 3.5 Fill in Rev Block Show Rev.0 as initial Release per ECO 007536 Erase Unused Rev Lines Move Border & Contents to 0,0 Use Lower-Lt Node Using Std Frame Demo - 4