As long as they are the same 5mm pitch, you don't get any more mechanical advantage, but the stiffness is a big plus. Especially on this machine's X axis, with the table all the way across to one side on the 840mm table length the machining forces in the X direction will be being taken by a long length of ballscrew. Both in compression and tension depending on machining direction of course. Basically I will fit the biggest screws I can fit in there, as long as they aren't out of my price range. |