Hello Francisco from Argentina, I have problems in grain loss in wheat, with the challenger 660. I read other forums and it seems that the cleaning area gets full of mog making the chaffer to be over loaded. I think that the solution is an air foil chaffer, here in Argentina air foil chaffer are not common. I try with agco parts dealers here but they told me that airfoil chaffers donít exist here. I was wondering if someone is so kind to send me some pictures and measurements so y can try to do one here. By measurements I mean how big are de holes, distance between them, distance between each section o row. Also the angle, it seems to me that it has an inclination. This information will help me to try to solve my problem.