Bale Wrapper Film Tensioner

I have an Ag Wrap bale wrapper that I have struggled with on and off with for years. I always ran 20 inch film in it, but 20 inch is getting to be a thing of the past. Recently tried some 30 inch and it doesnt work well at all. The film prestretcher doesn't stretch the film and its very loose at the top edge. I started looking into the pre stretcher and the film routing direction. It appears the 30 in film works best when the "fast roll" on the prestrecher is closest to the bale and the "slow roll" is closest to the film. This however is not the correct routing of the film according to the diagram. With this routing the stretcher tends to hinge and pull away from the roll of film, but it seams to work well. When I reverse the routing to how the diagram shows with the slow roll near the bale and the fast roll near the film roll the film is very loose and not stretched properly. 

   The manual on this machine is pretty pathetic. I did research a few tanco bale wrapper manuals and they almost all show the fast roll closest to the bale... Anybody with experience shed some light on how a prestretcher works best?

Thanks

Mike

Bale Wrapper Film Tensioner