Hello, the model works perfectly with the rig and constraints and it's easy with the 3d cursor in the rotor hub but if I move the 3d cursor everything change. So for this exercise I just need to live it in that position but I cannot imagine how to do if you have a more complex project and you have to move the 3d cursor. My solution was to apply a Limit Location but may there is a smarter solution. Any suggestion? Thanks. Carlo