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Basic Dimensioning Practices. Sacramento City College EDT 310. Dimensioning Practices. Dimensional information includes Size dimensions. Location dimensions. Notes. Dimensioning Practices. Size Dimensions Size dimensions provide the size of physical features. Diameter of holes Width
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Basic Dimensioning Practices Sacramento City College EDT 310 EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimensioning Practices • Dimensional information includes • Size dimensions. • Location dimensions. • Notes. EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimensioning Practices • Size Dimensions • Size dimensions provide the size of physical features. • Diameter of holes • Width • Length • Depth EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimensioning Practices • Location Dimensions • Location dimensions provide the location of physical features. • Location of holes from end • Datum Dimensioning • Chain Dimensioning • Location of windows/doors in buildings EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimensioning Practices • Notes • Notes give information about individual or specific features on the drawing. • They are attached to the feature with a leader line. EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimensions • Each drafting field uses a different type of dimensioning technique • Architectural. • Mechanical. • Civil. • Electronics. EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimensions • Drafters should place dimensions in accordance with company and industrystandards. • Use the company standard FIRST. • When no company standard exists, use industrystandards. EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimensioning Standards • ASME Y-14.5M-1994 Dimensioning and Tolerancing • Standard emphasized in the textbook. • M - means metric. • 1994 is the year it was published. • ASME is the American Society of Mechanical Engineers. EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimensioning Formats EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimensioning Formats • Unidirectional Dimensioning is • “Unidirectional” means one direction. • All dimension numbers and notes are placed horizontally on the drawing sheet. • Numbers are read from left to right when viewed from the bottom of the drawing sheet. EDT 310 - Chapter 18 - Basic Dimensioning Practices
Aligned Dimensioning • Aligned Dimensioning is • Used on architectural drawings. • Horizontal dimensions are read horizontally. • Vertical dimensions are read vertically from the right edge of the sheet. EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimension Styles used by Particular Field of Work EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimensions • Mechanical Field. • Uses Unidirectional dimensioning • Dimensioning parts. • Dimension Characteristics • Uses arrowheads for terminators. • Dimension line is broken • Dimension number is centered inside dimension line. EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimensions • Architectural Field. • Uses Aligned dimensioning • Dimension Characteristics • Uses “tic” marks for terminators. • Dimension line is unbroken. • Dimension number is centered over dimension line. • Dimension is aligned with surface. EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimensioning Practices EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimensioning Practices • Dimensioning practices depend on • Product requirements. • What are you making? • Manufacturing accuracy. • Extreme precision vs approximate dimensions. • Standards. • What dimension standards exist for your industry? • Tradition. • How has your industry dimensioned in the past? EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimensioning Practices • Compare dimensioning practices for: • Automobile. (decimal inches) • Architecture. (feet, inches, fractions of inch) • Microprocessor chip. (1/10,000 to 1/100,000 of an inch • Civil. (Miles or kilometers) • Each dimension type is appropriate for that discipline. EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimensioning Practices • Precision is indicated by decimal places • Automobile. (decimal inches) • 3 inches vs 3.0010 inches • Architecture. • 40.343245 feet (???) !! • Civil. • 40.365789 miles (???) !! • Precision must be appropriate for that discipline. EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimensioning Practices • The number of decimal places shown on a dimension increases manufacturing costs! • Paper weight measurements • 3.0000” x 4.0000” x 2.0000” • Vs • 3” x 4” x 2” EDT 310 - Chapter 18 - Basic Dimensioning Practices
AutoCAD Dimensioning Commands EDT 310 - Chapter 18 - Basic Dimensioning Practices
DLI DIMLINEAR DAL DIMALIGNED DAN DIMANGULAR DBA DIMBASELINE DCE DIMCENTER DCO DIMCONTINUE DED DIMEDIT DRA DIMRADIUS DDI DIMDIAMETER DOR DIMORDINATE DOV DIMOVERRIDE DST DIMSTYLE LE LEADER Dimensioning Commands EDT 310 - Chapter 18 - Basic Dimensioning Practices
The DIMLINEAR Command EDT 310 - Chapter 18 - Basic Dimensioning Practices
DIMLINEAR Command • Use DIMLINEAR command for • Length • Width • Depth • Use DIMLINEAR for • Linear dimensions – (X,Y, Z) • Horizontal • Vertical • Slanted surfaces EDT 310 - Chapter 18 - Basic Dimensioning Practices
DIMLINEAR Command • All dimension components are placed automatically by AutoCAD. • Extension lines. • Dimension lines. • Dimension text and arrowheads. EDT 310 - Chapter 18 - Basic Dimensioning Practices
DIMLINEAR Command • To DIMLINEAR command: • Pick the LinearDimensionbutton on the Dimension toolbar. • OR • Pick Linear from the Dimension pull-down menu. • OR • Type DLI or DIMLINEAR at the Command: prompt. EDT 310 - Chapter 18 - Basic Dimensioning Practices
DIMLINEAR Command • Command Sequence: Command: DLI or DIMLINEAR Pick First extension line origin. Pick Second extension line origin. Pick Location of dimension. EDT 310 - Chapter 18 - Basic Dimensioning Practices
First Extension Point EDT 310 - Chapter 18 - Basic Dimensioning Practices
Second Extension Point EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimension Location EDT 310 - Chapter 18 - Basic Dimensioning Practices
DIMLINEAR Command • When picking extension line origins: • Use one of the OSNAP modes for accuracy. • ENDpoint is a good one to use. EDT 310 - Chapter 18 - Basic Dimensioning Practices
DIMLINEAR Command • The DIMLINEAR command allows you to generate dimensions that are • Horizontal. • Vertical. • Aligned with a slanted surface. • Rotated at a specified angle. EDT 310 - Chapter 18 - Basic Dimensioning Practices
DIMLINEAR Command • Command: DIMLINEAR • The following prompt appears: Dimension line location (Mtext/Text/Angle/Horizontal Vertical/Rotated) • Notice submenu choices • Mtext • Text • Angle • Horizontal • Vertical • Rotated EDT 310 - Chapter 18 - Basic Dimensioning Practices
DIMLINEAR Command • Dimension line location • Is the default option selection. • Click the location where you want the dimension line. EDT 310 - Chapter 18 - Basic Dimensioning Practices
DIMLINEAR Command • Mtext • Accesses the Multiline Text Editor. • The << >> (Chevrons) indicate the current dimension value. • The < > is an intelligent value. • Normally, you should NOT delete the < >. • If you want the dimension changed, delete < >. EDT 310 - Chapter 18 - Basic Dimensioning Practices
MTEXT Option EDT 310 - Chapter 18 - Basic Dimensioning Practices
DIMLINEAR Command • Text (Uses DTEXT) • Uses the Command Line to change the dimension text. • Angle • Allows you to change the dimension text angle. • Horizontal • Sets dimensions to horizontal distances only. • Vertical • Sets dimensions to vertical distances only. • Rotated • Allows you to change the angle for dimension line. EDT 310 - Chapter 18 - Basic Dimensioning Practices
Text Option chosen EDT 310 - Chapter 18 - Basic Dimensioning Practices
Angle EDT 310 - Chapter 18 - Basic Dimensioning Practices
Vertical Horizontal EDT 310 - Chapter 18 - Basic Dimensioning Practices
Rotated EDT 310 - Chapter 18 - Basic Dimensioning Practices
The DIMALIGNED Command EDT 310 - Chapter 18 - Basic Dimensioning Practices
Dimensioning Angled Surfaces • DIMALIGNED • Use for dimensioning a surface drawn at an angle. • DIMALIGNED • functions similarly to the DIMLINEAR command • aligns dimension lines with the surface. EDT 310 - Chapter 18 - Basic Dimensioning Practices