Thiết kế flash - Dimensioning

Dimensioning Definition Size and shapePositionSurface texture or Geometric characteristicOf a featureA dimension is a numerical value that defines the: UnitsMillimeters (mm) in the metric systemInches in the English system The default dimensional units in most CAD systems are:NOTE:Dimensions in millimeters typically expressed as whole numbersDimensions in inches typically expressed to two decimal place accuracyTerminologyLeader – Line (w/ arrow) drawn from a feature to a noteReference dimension – Numerical value provided for information only and not used in fabrication of the part NOTE: Dimension text heights are typically 3 mm, and are uniform throughout the drawing Dimensioning Guidelines for Prisms-1Do not repeat dimensionsDimension most descriptive view of feature being dimensionedDimension between viewsOmit one intermediate dimensionSmaller dimensions inside of larger dimensionsExtension lines may cross object lines and other extension linesDimensioning Guidelines for Prisms-2Avoid dimensioning inside an objectDimension to visible object lines, not to hidden linesDimensioning Rules/Guidelines for Cylinders and Arcs Dimension diameter of cylindrical parts in their rectangular viewsDimension diameter of cylindrical holes in their circular viewsDimension radius of fillets and rounds (180 degrees or less)Locate center of holes C’est tout!