About this 3D model

I am in the midst (a slow midst) of building a CNC mill and my frugal side didn't want to fork out the cash for proper anti backlash threads/nuts. My local Bunnings store sold relatively cheap 1/2" threads and so I designed this as a cheap alternative makeshift anti backlash system. It fits quite snugly and seems to remove all the play but is not yet tested. It uses two nuts and a spring I managed to remove from an old office printer. The .skp is uploaded for modifying.