Question on implement horsepower ranges

[scoobydufus]

Hi,

I'm a tractor newbie and am just learning the ropes. I've inherited a 78" flail mower with a hp requirement of 30-75hp. How important is it to have PTO horsepower in the middle of the range? I'm a computer nerd and in that arena the minimum spec usually means it'll technically run but be barely usable. Is that the same case here? Are there any rules of thumb you guys use?

Thanks!
-Scoob

 

[Halftrack]

Depends on what your plans are for the mower. I you plan to mow grass and keep a pasture trimmed every 2 weeks, 30 hp will get you by. If you plan to wade into 2 to 3 foot high weeds, you will wish you had 70 hp. I have 33hp and it is extremely slow in the neighbor's old horse pasture with my 6.5' Ford 917, when he wants it knocked down. Rule of thumb- less hp=slow going.

 

[LD1]

Agreed. If it's a finish cut flail that is just clipping a few inches of grass off every week or two, 30 would do just fine.

If it's a rough cut flail, and you are using on overgrowth similar to what you would want a bushhog for.....flails are power hogs and you will want all you can get.

 

[RedNeckRacin]

Agreed, don't forget transmission type and terrain can play into that number to. Even species of grass (if you really want to wander into the weeds) can cut very differently. Manufacturers spec their mowers out to give you an idea of what their equipment needs to run effectively. The trick is figuring out if their numbers are conservative or generous. :thumbsup:

 

[Fallon]

My 32hp (25ish PTO) L3200 handles my 72" 917 flail just fine in my field which doesn't get that gnarly at all.

With most PTO implements, you can just slow down & fudge a bit with minimum HP requirements if your 3pt will lift stuff.

Max HP ratings can be looked in a few ways. The sheer pin or slip clutch (belt on a flail) is the weak spot & will blow before important parts, so to much power isn't that relevant there. If its ground engaging your problem is to much traction. Implements should be rated by tractor weight (which equals traction) instead of HP. But weight & HP usually corelate pretty well in the real world for most tractors. If you have a 30hp rated box blade & you catch a root or rock, your tractor will spin its tires or stall. If you pull the same light 30 HP box blade with a 100hp tractor & snag the same rock or root, you may or may not hear or feel the box blade turning into a pretzel as all that traction pulls it apart.

 

[RPW]

Sharp knives will allow less horsepower to a point