Spinner for a particulate material spreader

An apparatus for broadcasting particulate or granular material over a ground surface, the apparatus comprising:

• a pair of variable-speed spinners and a material conveyor, the pair of variable-speed spinners being positioned below a discharge end of the material conveyor, wherein each of said pair of variable-speed spinners comprises a dish-shaped disk having a center that is below a horizontal plane defined by a periphery of the dish-shaped disk,
• a plurality of interchangeable radially-disposed fins positioned on an upper side of each dish-shaped disk and radiating outwardly from a center of the dish-shaped disk with an adjustable angle relative to a radial of the dish-shaped disk, each of the fins having a top edge portion that is angled relative to a portion of the fin that is attached to the dish-shaped disk, at least a portion of the fin extending beyond a periphery of the dish-shaped disk;
• and
• an adjustable flow divider between the material conveyor and the spinner for directing and adjusting a flow of the material from the material conveyor onto the pair of variable-speed spinners,
• wherein each of the pair of variable-speed spinners is able to spin at a variable rotational speed and is positioned to receive material from the flow divider at a selected location about half way along a length of the fins such that the material is caught by portions of the fins traveling at a speed of about 60 to 70 feet per second and is accelerated to a velocity of about 110 to 157 feet per second at an end of the fins' radial length.