Abstract: Swathed grain is picked up by a conventional pick-up and fed into the side of one end of a transversly situated rotary impeller assembly which moves the crop in a spiral motion against threshing grates on the lower portion and spiral fins on the upper portion. The crop reaches the other end of the impeller assembly and is transferred to one end of a second transversly situated rotary impeller assembly whereupon the action is repeated until the crop reaches the other end of the second assembly whereupon the crop with the majority of grain removed, is discharged at right angles to the axis of the impeller assembly and into a final beater assembly. The threshed and separated grain falls from the impeller assemblies to a grain pan and is cleaned by two sieve assemblies which extend the full width of the impeller assemblies. Unthreshed grain is returned to a re-threshing unit mounted at one end of the beater.