All that matters with an a/b nut is that one nut is firmly bearing on one screw face and the opposing nut is firmly bearing on the opposite face. The relative position of the two is irrelevant as long as they are on opposing faces.
I think the layout is fine either way, compression or tension, you just need to keep the nuts from moving axially relative to one another (i.e. bushes or guide pins), and to remove any end float. I would suspect there is a little of both going on here, but the basic arrangement itself is sound. |