If I want the cross section in an exact spot, is there a way lock it to the front plane or a feature?
Dragging and dropping isn't quite a fine enough control?
Can I get to a co-planar or some other type of constraint?
right click on the section line and choose "edit sketch" - this will give you all of the sketch tool to control is position.
It would be nice to be able to lock it to a plane. But I was able to get it on center with your help.
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