convenient level directly in front of the operator the float belt 65 is loosened but does not need to be removed from the drive sheave to remove the saw cylinder it should be therefore apparent that the operation of opening the gratefall and removing the saw cylinder for sharpening or maintenance is greatly simplified note that since the doffing roll is not mounted to the gratefall assembly 41 it does not move and doffing roll belt 92 remains tensioned between sheave 63 and doffing drive sheave 93 in as much as the float and doffing roller are driven by the same motor it should be noted that jackscrews 81 82 provide a positive mechanical linkage to the gratefall assembly 41 thus if electrical power is lost during the movement of the gratefall the jackscrew will stop and the gratefall assembly will remain in its then current position rather than falling under the influence of gravity as could occur with a hydraulic system it is also noteworthy that limit switches are in the circuit energizing saw motor 21 and float motor 22 these limit switches open when the gratefall assembly begins to move from the closed position de energizing the saw circuit and thus insuring that none of the belts motors or sheaves are energized during the saw cylinder change out process it should be noted that feeder 11 is the same width as saw cylinder 22 thus seed entering the float chamber 17 and urged toward the saws 24 is able to pass vertically through the delinter without the need to migrate laterally as was the case in the delinter shown in the 39 448 patent accordingly the seed can be processed more quickly and no build up.