"They'll save 10 to 15% more grain per acre," says Gary Porter, manufacturer of new sieve extenders for combines that add an extra 8 in. of cleaning surface to standard combine sieves.

The bolt-on extenders simply attach to the rear of the sieves across the entire width of the machine, spaced by 6 "fish-back" separators that help flip crop material over.

To this point, Porter has only mounted the extenders on Deere combines but he says he's looking at other models. "Sieves on Deere combines were not built long enough at the factory. Combines built by Deere in the past year or so have been fitted with longer sieves that don't need an extender," he notes.

Stan Bothman and his son Mike, who farm near Rosalia, Wash., outfitted their 6620 Deere with Porter's extenders and told FARM SHOW they paid for themselves in the first field.

Installation requires only minor drilling to bolt the extenders to existing sieves.