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Next step is to draw orphan joints/nodes to the location where the centerline of the trunnion will be welded to the elbow. In this example we click the Draw joint icon where we enter -18" in the Z direction and click the two elbow joints as shown below left to add joints where the trunnion will be welded to the elbow. Next, assign a Body constraint to each pair of joints shown in order to create a zero weight rigid connection. As shown below right, there needs to be a separate Body constraint for each pair of joints.
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