triplus wrote:When you use expression and take some parameter of parent feature to define geometry of the child feature (through expression). You end up in the same (topology) situation as when using Assembly 2 workbench to add a constraint between 2 features. There is no real difference involved.
I thought that's the main reason of PartDesign Next, no? You have datum plane to map to instead of the actual model shape. Besides, if you really want to have a parent/child relationship. Who should be the parent? The more complex and volatile actual model, or the potentially much simpler constraint base geometry? This decision making is more evident when you build your part using PartDesign. A threaded socket in the model is a simple cylinder pocket in early steps. And that cylinder comes from a sketch on a datum plane. You can either choose that actual cylinder to be the constraint base, or better, the sketch itself, or a dedicated geometry derived from that sketch where you can do all kinds of magic stuff without worrying of topological change of the model. And yet this constraint geometry and the model is linked through the same sketch. So, you get the auto update you want.
I don't think assembly2 is capable of selecting anything but the actual model shape subelement as constraint base.
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