Simplified Assembly components are shifted from the designed geometry after using Auto-Simplify
The Auto-Simplify algorithm scales components when necessary, very slightly, to ensure that the Boolean operation will succeed without causing a non-manifold error, so that a single body representation of the model can be created.
Therefore, depending on the simplification method you use, the dimensions of the simplified parts may not be precisely identical to the original components. Simplified parts are intended to provide a performant visual representation of the designed part. Where precision is critical to your models, you may achieve more accurate results using as-designed parts.
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