Creating Primary Members from Reference Planes To create primary members from reference planes: Click Ref Plane Member for Primary Member Type. For Reference Set, select the following planes by expanding Reference Data in the flyout FeatureManager design tree. You can also display planes by clicking View > Hide/Show > Planes. For Start and End Plane, click Base and Third. These planes are parallel and define the length of the members. For Plane Set 1, click Right Plane. This plane is perpendicular and intersects with the Start and End Plane. For Plane Set 2, click Front-1 and Back. Plane Set 2 intersects with Plane Set 1. They define the location of the two members that are in the middle of the structure. Unpin the PropertyManager and click . The primary members of the structural system are complete. Parent topicPrimary Members