that is a good point E30Legend: If you model fails the first time: check for these issue:
Is it to complex for one object. - There is just so much going on that physics cant deal with it whole. Split it up into logical parts if needed, and place all at the same insert point.
Collapse like pieces into sub objects in the model. - This works most of the time. Some times you need to collapse completely.
To many vertices - Don't quote me on the exact number. But do a weld vertices, for the smallest size that the editor will let you do. .001 or 1/64". You will be surprised on how many vertices reduction can happen just there. and the model might work then.
Just some of the many things to try. Just because you could not get it there once, or even ten times, over time you will refine your work flow and, you will see less and less of these issues, as they mostly are learning issues.
Thank you
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