How big can I go? (cutter)

[Fastball]

Hi, all....considering a rotary cutter (brush hog). I've got a Kubota L2900 (29 hp)
Mostly just rough grass and knee high weeds, not a lot of actual brush.
I see in my "used stuff" site that there are a few options out there, ranging from 42 inches to 72.
How big/small should I go, given the parameters given?
Thanks.

 

[Fallon]

I ran a 7' flail behind my 32hp (25pto) L3200. It wouldn't have lifted a 7' rotary , but would have spun it if I ran slow. It ran a 5' fine & might have ran a 6'. I'd shoot for something that matches your tractor width or just a hair wider.

 

[Areeves08]

I had a John Deere 3033R and a 6' Woods BB72X. It was great for mowing on a regular basis if I kept up with things. It wasn't so great when weeds and grass grew knee-high or taller. If you don't want to feel like you're crawling along, I think the 5' is the best option so long as it covers your tire width. You want a minimum of 5 PTO HP per foot of cutter in a single spindle. More is better.

 

[dieselcrawler]

X2 on the 5' brush hog being a good match. I run a 5' with my JD 3005, w/27 hp, it bogs down in thick stuff, but it's a good compromise of power to width.

 

[Shaneard]

I agree with the 5HP PTO per foot of cutter, not engine PTO though. The more HP on the cutter shaft the better.

 

[RSKY]

Your manual will have factory recommendations for implement sizes. Just make sure you have one wide enough to cover your tracks. We use a 5' behind 22-hp and a 6' behind 52-hp with a 125-hp pulling a 15'. Thick grass will pull the tractor harder than weeds and brush. With 29-hp I would go with a 6'. Since some of the area we mow has small ditches and some is very rough I am of the philosophy that wider and slower is better. Saves the kidneys and back.

RSKY

 

[CobyRupert]

What's the most weight your 3PTH and tractor can lift and handle and how fast do you want to go? That is: horsepower is just a number that means how FAST you can do work (Assuming you can lift it and get it spinning.)
All other things being equal, having 1/2 the horsepower means you can only go 1/2 as fast; having 2x the horsepower means you can 2x faster.
In reality, one is not running at full load all the time, and you can control "full load" by your speed.

 

[bspeedy]

Your grand L will handle a 6-foot cutter with no issues. Might have to slow down a bit if grass is really high. If cutting larger fields is what you are doing, I would opt for the 6-footer. In most cases I would suggest a 5-foot cutter with the hp you have. Grand L is a different situation. Horsepower is the same as a smaller tractor, but the Grand is a different animal.