feeding drum 700 the left fins 710 l however are mounted on the tube 720 so that its elongated face 711 l is disposed at an angle ml to the right of the plane perpendicular to the rotation axis 701 of the feeding drum 700 this particular arrangement of fins 710 r 710 l allow the feeding drum 700 to push the material into two new directions left to right u2014 thanks to left fins 710 l u2014 and right to left u2014 thanks to right fins 710 r u2014 importantly although the preferred configuration exemplified in the figures shows the feed drum 700 with one half of the tube 720 filled with left fins 7101 and the other half filled with right fins 710 r it could be desired to have greater amounts of u2014 movements u2014 to the material by the alternate arrangement of the left and right fins fins 710 l 710 r without affecting the spectrum scope of the following invention it could be also noticed that changes on the angles mr ml of the fins 710 r 710 l could be implemented without affecting the spectrum scope of the following invention fig3 exemplifies an important aspect of the present invention where the preferred geometric shape for the face 705 of the fin 710 u2014 that works in contact with the material to be.