Originally Posted by Wet_Boots
I remember the description of the ancient Safe-T-Lawn ball-drive rotors operation stressing how well the water flushed away anything from the wiper seal area, both rising and retracting. It was really more in the way of excessive flow-by, that they got away with on account of the wide (for then) diameter of the turret.
I remember them well. I believe they were "AP" models. I used them on my first install in '78. Good midrange rotor at the time but a pain in the posterior to adjust. They had 2 slotted screws you had to remove to take off the top cover to get at the adjustment disc. Kind of an impact like disc adjustment.