Tractor Sizing need your experience-bush hogging w/ low 30s HP vs 40s HP

[xtn]

50 acres? I'm figuring about an hour and a half.

https://www.youtube.com/watch?v=oPWO_C1rT34

 

[Ed of all trades]

50 acres? I'm figuring about an hour and a half.

https://www.youtube.com/watch?v=oPWO_C1rT34

That is cutting hay not bush hogging. Big dif. Ed

 

[LD1]

That is cutting hay not bush hogging. Big dif. Ed

And likely $500k worth of tractor/mower too

 

[RedNeckRacin]

And likely $500k worth of tractor/mower too

I imagine the repair bills also match!

 

[John_Mc]

The formula for theoretical capacity (100% efficiency) in acres/hour = speed(mph)*width (ft)/8.25. You can multiply this result by your estimate of field efficiency to obtain actual capacity.

Steve

Edit-- Some folks assume 82.5% efficiency and use the "quick and dirty" formula: acres/hour = speed(mph) * width (ft)/10.

Steve, is that formula allowing for any overlap when mowing, or do you just use the efficiency number to account for that?

 

[John_Mc]

Brush mowing with a 30-35 HP tractor vs a 40=45 HP tractor would call for a different size mower to make the best use of your tractor. I've heard a rough rule of thumb that you need about 5or 6 HP per foot of width on a single-arbor brush hog. For example: Lots of folks use a 5 footer behind a Ford 8N (30 HP, with about 27 HP at the PTO) with good results. A 6 footer is more than an 8N can comfprtably drive, unless you are just doing rather light mowing and keeping things mowed regularly.

I use a 5 foot brush hog behind my New Holland TC33D (33 HP HST, with about 27 HP at the PTO). THe tractor and mower are a good match, mowing about 10 acres a few times per year here in the Champlain Valley of Vermont (Hilly, but not too steep). If I had bought the TC40 or 45 (40 or 45 HP), I would have done with a 6 foot mower.

I have a couple of areas I let grow into saplings and only more every 3 years or so (for wildlife habitat purposes). I've found mowing the thick, heavy grass and weeds we get around here a couple times a year takes more HP than mowing the field of +/-3/4" saplings.

 

[smstonypoint]

Steve, is that formula allowing for any overlap when mowing, or do you just use the efficiency number to account for that?

The efficiency value allows for overlap and other factors (e.g., turning).

Steve

 

[GManBart]

For example: Lots of folks use a 5 footer behind a Ford 8N (30 HP, with about 27 HP at the PTO) with good results. A 6 footer is more than an 8N can comfprtably drive, unless you are just doing rather light mowing and keeping things mowed regularly.

Actually, early 8Ns only had 18hp at the PTO and later 8Ns had 23hp at the PTO. Mine (built in late 47) would run a 5' cutter okay, but even lifting a 6' cutter was iffy.

 

[terryknight]

DON'T KNOW ABOUT BUSH hogging, but running a 7.5 ft finish mower cutting ~8 acres used to take ~3 hrs behind a 32 PTO HP tractor it now takes a little less than 2 behind a 45 PTO HP tractor. I can run at a higher speed and still get the same cut. behind the 32 HP tractor we ran a 5ft bush hog, behind the 45 HP tractor we run a 6ft bush hog, I would use a 8ft if I could find a decent one cheaper.

 

[TJP89]

You have to match the mower with the tractor, and match the mower to what you're mowing. I have a 5ft rotary cutter on my 34HP tractor. If I can run it over, I can cut it, no problem, and I'm probably doing 4 mph usually. But I wouldn't want to do 50 acres with that, its too small. You need to figure the amount of mower you need to cut your field(s), then go from there. If you already have the mower, match the tractor. 1ft of cutting width for every 5HP of PTO power is the general rule. If you have the tractor, this is beside the point, as the best cutter is the one that best matches the tractor. A bigger one won't speed things up because it will bog the tractor down.

I've only skimmed the thread so I may have missed it, but you haven't given us what exactly you're planning to do, or what the equipment situation is. That can take this discussion from hypothetical to real facts, info and help.