Data integrity checklist

• Data integrity rules are independent of viewing angle or display resolution.
• Don't just eyeball it. Understand the CAD/CAM data, not just the display.
• Understand the difference between the dimension text and the geometry data, and when each is used down-stream.
• Use appropriate system tolerances for CAD models.
• All geometry should be drawn to full scale.
• Use layers to separate geometry for parts in assemblies and for non-geometric data.
• Keep models clean and model size small.
• Let the computer do the math for geometric construction.
• Use the simplest possible geometry.
• Operate on intersecting rather than tangent geometry.
• Avoid coincident vertices, edges, and faces.
• Create geometry only once. Avoid duplicate entities.
• Use object snaps during construction to ensure that geometry endpoints meet, leaving no gaps.
• Wherever possible, represent continuous object lines with a single line entity.
• Use clearance and interference checking tools.
• Dimensions should exactly match the size of the geometry they are dimensioning. Thus, all dimensions should be computer-generated.
• Delete unnecessary entities before transfers, including lines and notes used for construction.
• Note the manufacturing tolerances of the final part in the CAD file on the layers containing dimensions. This includes any block tolerances.
• The sender of CAD/CAM data should accompany each file with at least one 3D isometric picture of the entire part, complete with scale or dimensions.

Source:
Hap Stokes, Engineering Consultant