Rotary cutting

[BuzzardA91]

I am buying a rotary cutter for a 3-4 acre field but have never used one. I know how to size the hp but how size the width? The width of my tractor is 66". Can I go with a 5' or is a 6' a must. I will miss a few inches in tight spots with the 5' or can you off set the cutter a few inches by locking the lower arms off center on the 3 point? I don't care about saving time.

Also my 3 pt hitch is rated for 2,200 pounds 24" out. Obviously a rotary cutter is rather large, heavy and long. What weight would be safe to get?

 

[nuffer460]

I am running an IH 411 6' rotory mower. Very heavy unit. I put it behind my NorTrac 254 Tractor. It is at the very limits of my tractor. My tractor is gear drive, not a hydraustat. So I don't lose allot of hp at the pto. I would not have tried this if not for a local Bobcat Dealer. He said that the frame size and tire size are good for a 6' rotory. If the engine temp goes up a little. I just cut a narrower swath. I do have to stop every so often to clean off the radiator screen. I also don't actually lift the whole unit off the ground. It runs down the road on the rear tail wheel just fine.

 

[Soundguy]

if you have the pto hp and safe weight capacity both on the 3pt and fram for a 6' and don't have obstacles.. go 6'

 

[Mark Page]

You don't mention the tractor's horse power. The rule of thumb is 5hp/ft, this would call for a 30 horse machine with a 6 foot hog. I used to use a 6ft mower with a 35 horse Massey and never had a problem. I could lift it all the way up and back down on multi-flora-rose bushes.

 

[Mark Page]

You don't mention the tractor's horse power. The rule of thumb is 5hp/ft, this would call for a 30 horse machine with a 6 foot hog. I used to use a 6ft mower with a 35 horse Massey and never had a problem. I could lift it all the way up and back down on multi-flora-rose bushes.

 

[Jerry/MT]

Conservative rule of thumb is 5 hp per foot of mower width.( If you are not going to cut four foot high weedy fields, 3.5 hp per foot will most likely be adequate.)
Get the width that covers your rear track, probably around 6 ft. That imples ~21.5-30 pto hp. ( A five footer would require ~ 17.5-25 pto hp.)The lightweight mowers are around 450 -500 lbs, the medium duty ones around 700-750 lbs and the heavy duty go 1000 lbs and up. You have adequate capability to raise any of these with the three point hitch but remember the heavier the mower the lighter the front end becomes unless you ballast the front. The price is proportional to the weight.
You can't off set the usual rotary cutter however you can probably find an offset mower but you'll pay a premium for it.

If your just mowing normal high grass( 2-3 ft tall) on 3-5 acres, the light weight will probably be a cost effective solution for you. If you have rocky ground and tall weeds and grass, the medium weight 5 foot model might be a better solution.

Your $'s, your choice.

 

[BuzzardA91]

Thank you. I didn't mention the HP because I did not want to cloud the issue, that part I understand.

I more wanted to know what the disadvantages of going with a 5 foot MX5 vs the 6' frontier. About the same price and weight but the MX 5 is way heavier duty. Mow time would be longer but what else? The width is 66" of the tractor some would be 3" short on each side. Is that going to be a problem?

My field the Frontier will be fine but I may want to do others and am worried about hitting something or thicker stuff.

Also JD doesn't list my tractor under the MX6 but it does the 6' frontier and the MX5. Not a HP issue, I have 32.5 PTO hp. I'm guessing it is the weight difference? Or it could just be a mistake, I have found several in the JD brochures.

 

[deere5105]

Go MX5 and be done. Will last you many years. If you are cutting anything thick, the MX6 will likely be a HEAVY load on 32.5 PTO HP.

 

[BuzzardA91]

Thank you. What about being 3" short on each side of width of tires? Is that an issue, I have never used one.

 

[TerryR]

I will miss a few inches in tight spots with the 5' or can you off set the cutter a few inches by locking the lower arms off center on the 3 point? I don't care about saving time.

I have my tires set at max width because of the significant side-hills on my field, so my cutter is about a foot narrower than the wheels. I do as you suggest, pulling the arms all the way to one side so the cutter matches the wheels on that side. Thus I have uncut wheel tracks only on the first cut through a place. It works fine - just a bit of trouble to re-adjust the arms after mounting or dismounting the cutter.

Terry