I have an assembly with the end cap fully constrainted to the assembly origin, the main "U" tube fully constrained to the end cap, and a second "J" tube constrained concentric to the axis of an outlet port but free to rotate about it (I can drag it to confirm). I defined an assembly reference plane using the outlet port axis (which the "J" tube rotates about) and another outlet in the endcap. When I ask SW to mate the plane of the (free to rotate) "J" tube as parallel to the assembly plane it moves the endcap, totally ignoring the constraint that connects it to the main tube and to the assembly origin rather that rotate the outlet tube. Any ideas how to get SW to not ignore the existing mates? I can visually rotate the part to the correct orientation. After the mate I can edit the concentric mate of the "U" tube to the end cap and SW says it is solved but you can visually see that it is not.