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That said, everyone who's worked with me knows im a notorious hater of Filled Regions, in Wall Sections. Even with the capability to lock/constrain them to the modeled objects, i always take the side of using Edit Cut Profile on the cut patterns of the modeled objects, wherever possible.
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When you attempt it, you are able to get in to sketch mode, and you can work until you try to finish the sketch. That is when you get the ominous "Fatal Error has occurred" window.
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As the self proclaimed "Model Nazi" you can imagine the amount of anxiety i had, at having to concede to a project team that they could detail this portion of the building using Filled Regions, haha.
These walls presented another interesting issue as well:
When i went to place a door in the wall, the door was only able to be hosted at the very base of the wall (Right at the Level T/O Slab). As i was trying to place an Access Door from the roof, this was not useable. It would not allow us to place the door on the ground and raise it up, eiher. We
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The fix for this was interesting: We were able to place WINDOWS inthe walls without incident, so we used Edit Family to make a copyof the door family. We then changed the families catagory to a Window Family, and then we placed it in the tower. AFTER having placed the "window", we were then able to go back to the fmaily, and change its catagory back to a Door Family. This let it stay placed in the desired location in the tapering wall, while still scheduling it as a door.
Fun times with Tapering Walls!