Cutting a field of grass is a straightforward and satisfying process, given a suitably powered mover. A tractor with a rotary topper to hang on its three-point linkage and power-take-off will make short work of the task.
[Donn DIY] had an agricultural quad-bike, but when it came to mowing its lack of a power-take-off meant it wasn’t much use. When he saw a home-made mower for a quad-bike online he had to give it a go himself, and came up with his own take on a mower made from junk.
He started with the rear axle and differential from a Russian built Lada, which he reconditioned, before mounting in a wooden jig with its input shaft pointing upwards. He then made a frame for three mower shafts, onto which he mounted his custom-made rotors and their machined bearing housings. Some pulley machining, and he could then link the rotor shafts to the differential with a series of V-belts and a further shaft to step up the rotor speed.
He wasn’t finished there, after the rotors came a lever mechanism for lifting the cutters off the ground, and a pair of weight baskets to ensure traction was maintained. The result is a mover that takes its drive from its wheels, and cuts grass very effectively when towed behind the quad-bike. The unguarded blades would probably give a farm insurance assessor an apoplexy, but for the purposes of the video below the break at least we can see everything.