The predominant failure will be failure of the knives at the bolt hole. As noted by buickanddeere the knives are pulling (1000/540)^2 = 3.43 times as hard on their moorings. No problem except for the violent abuse suffered when hitting solid objects. Damage>crack>failure> 10# projectile travelling 400ft/sec. THE safest place within shouting distance is ON the tractor.
,,,Between he and LD1 I think everything was addressed -- except different blade designs, length, shape, etc. Most blades are long and shaped to swing well below the stump jumper. This makes them heavy and the shape results in a twist/twitch when they hit something. At least some bushogs from the '60s used a solid, shaped cutter bar with short flat swinging knives at the ends. This prevents the twist as well as applying lighter pull on the moorings. With my JD127 Gyramor as example, the same size blade bolts are used, but to hold a 10" long knife weighing ~5#. I havnt had a blade failure but the holes do elongate - and Im not sure its all from wear. Recently Ive experimented with cutting at 750rpm drive speed. Iv looked hard and for the life of me I cant see any improvement in grass. WEIRD. :confused2:
I think there would be an advantage for trees but I havnt tried it yet.
larry
