GR7 Construction Tolerances Further Information...

Applying the Tolerances Rule

Using tight Construction Tolerances is more important later in the design process:

Illustration of the Design Process

Breaking the Rule

You can ignore the tolerance settings if you are:

The key setting is Maximum Gap Tolerance

The key setting for data transfer is the Maximum Gap Tolerance, as this determines whether surfaces can be considered 'joined' when transfered to a solid-modelling or production CAD system.

Gaps between surfaces

Why not set the tolerances to the tightest possible settings?

Each surface tool (Skin, Rail etc.) or operation (Intersect, Trim, Align etc.) refers to the Construction Tolerance settings to determine how accurately to be applied. Greater accuracy can lead to longer calculation times, so try to select the right settings for the stage of work that you are at.

As you gain production experience with Alias, you will become more confident in choosing how and when to apply different tolerance settings. As a beginner, the easiest choice is to use one of the Construction Pre-sets.

Further Information on Construction Tolerances

For more detailed information on construction tolerances: