patrickg
Veteran Member
Hard to add much after Bird gives a response but I would mention that the 5HP/ft can only be an approximation in a certain limited size range as the HP requirement, I think, goes up at the square of the blade length. A six ft cut would require about 2.25 times the HP of a 4 ft cut in the same material, same forward speed, etc.
I have 39 PTO HP to a 6 ft mower and routinely cut brush/saplings over 2 inches. For big stuff, I back over it to avoid damage to the tender underbelly (need skid pan). For insane attempts at cutting trees, I raise the cutter way up, back over the tree, and lower the cutter down, eating the tree like over enthusiastic pencil sharpening. Every so often I stall the motor when I let the speed drop and lose hydraulic power to raise the cutter to avoid the stall. If I am really quick and have the presence of mind, I can kick in the clutch and disengage the PTO.
I recently impaled the engine compartment with a 4 ft length of 1 1/2 inch diameter branch. I ididn't notice until I stopped the engine (to remove debris from the screens in front of the radiator) and it woudln't crank back up. Wouldn't spin the starter. Used a come along to remove the stick. Broke a rope, doubled it and broke that, changed rope and pulled the stick out. It has wedged near the starter and touched the clutch linkage. I thought maybe the clutch "safety lockout" was stopping my start attempts but not so. I ran my finigers around where the stick had been and felt a loose wire. It "snapped" back into place on the side of the starter (like a snap on a western shirt) and she cranked right up.
Moral of the story... BE CAREFUL when brush hogging!
Patrick
I have 39 PTO HP to a 6 ft mower and routinely cut brush/saplings over 2 inches. For big stuff, I back over it to avoid damage to the tender underbelly (need skid pan). For insane attempts at cutting trees, I raise the cutter way up, back over the tree, and lower the cutter down, eating the tree like over enthusiastic pencil sharpening. Every so often I stall the motor when I let the speed drop and lose hydraulic power to raise the cutter to avoid the stall. If I am really quick and have the presence of mind, I can kick in the clutch and disengage the PTO.
I recently impaled the engine compartment with a 4 ft length of 1 1/2 inch diameter branch. I ididn't notice until I stopped the engine (to remove debris from the screens in front of the radiator) and it woudln't crank back up. Wouldn't spin the starter. Used a come along to remove the stick. Broke a rope, doubled it and broke that, changed rope and pulled the stick out. It has wedged near the starter and touched the clutch linkage. I thought maybe the clutch "safety lockout" was stopping my start attempts but not so. I ran my finigers around where the stick had been and felt a loose wire. It "snapped" back into place on the side of the starter (like a snap on a western shirt) and she cranked right up.
Moral of the story... BE CAREFUL when brush hogging!
Patrick