About Model Size and Data Precision

Best practices for the Inventor modeling envelope.

When modeling parts and features, including assembly features, keep in mind Inventor’s modeling envelope.

Part geometry or features should be less than 100 meters in size and not farther than ±100m from the part document origin.

Assembly features, modeling features defined in the assembly which involve one or more parts, must be confined to the same parameters within the assembly document. Additionally, any model participating in an assembly feature must also be confined within ±100m from origin and must be smaller than 100m in length.

The Autodesk Shape Manager (ASM) geometric modeling kernel uses 64-bit floating point computations and Inventor sets the modeling tolerance/resolution (i.e. minimum dimension size) to 1.0e-8 meters, therefore the modeling space in Inventor has an upper limit described by a cube of ±100m x ±100m x ±100m centered at the document origin. Any piece of geometry (edge, face, or body) should be contained within those limits. When geometry exceeds these limits, any modeling operations or view constructions on the geometry can lead to unpredictable behavior due to a lack of numerical precision. It is highly recommended to keep any geometry within these limits.