Rotary Cutter Acreage per hour question

irsmun · Nov 9, 2013

I know this will be a subjective question but I have to start somewhere. I recently purchased an 8' rotary cutter. I haven't had the chance to use it but I have advertised its availability. I am trying to base my rate by how long it will take me to cut. I am not one who likes to leave clients with an open ended invoice by saying X $ per hour. I like to say, "I'll do it for X $". I realize there are many variables to consider such as whats being cut, height, obstacles etc. But for the sake of simplicity, on an open field with 2-3' grass and weeds, what is a ballpark on acres per hour to cut with an 8' cutter?

I know this type of question has been asked many times. I am not trying to repeat it. I don't want a formula or anything. I am looking for an answer from experience from those who have used one.

JasG · Nov 9, 2013

IMO your tractor is small for a 8' rotary cutter.

Your best bet is to use the unit yourself and see how long it takes you to cover a certain area. The times will vary greatly based on each machine. A tractor with a higher HP will cover the ground much faster than lower ones. It makes a huge difference.

jenkinsph · Nov 9, 2013

What would do you the most good was if you go out and cut a few acres and see for yourself. No sarcasm intended either, it is just so open ended that I will often try something new and simply learn through practice.

Mathematically you could look at it this way 1 acre 43560 sq ft /8ft width=5445 add 10% for overlap and get 5989 /5280=1.134miles That tells me I could cut almost an acre/hour for each mile/hr I could average ballpark. So 4.5 mph average would be close to 4 acres/hour, so how fast you wan't to go makes a huge difference. Each job can be different the key is to know what the differences are. Seat time helps with this.

Chilly807 · Nov 9, 2013

The 5 footer I have will cut roughly 1.5 acres per hour, but that's highly dependent on how rough the fields are. I would think, on average you should be able to cut 2 acres per hour, maybe a little better. That's assuming you have enough power to run the cutter at the maximum comfortable travel speed.

Sean

Degolyerent · Nov 10, 2013

As far as how much you can cut it depends on what gear you will be operating your tractor in and the speed it will be going in mph. Next figure out how much overlap you will have on average. Then deduct the amount of overlap off the width of the cutter( use inches ). Multiply the inches x the speed and divide by 100
Example:
8' wide cutter is 96" overlap is 10" so 96-10= 86"
multiply 86 x the speed of tractor, say 4.5 mph= 387
now divide 387 x 100 = 3.87 acres per hour
That does not include a efficiency factor, an example would be 80% so multiply x .80 = 3.09 acres per hour ( this will factor in some turns etc. )
Actual times will vary depending on situation
John

irsmun · Nov 10, 2013

Again, I understand times will vary. I also cut grass professionally with a commercial zero turn. I've cut enough that I can just look at a yard and give a pretty good estimate on time. But with this I have never used it and don't have a field lying around to go test it out...or I would. So replies that give me your approximate times on your size cutter at least help me get a feel for where I am.

As for the tractor size, I went in to the dealer with the intention of buying both a tractor and this cutter. I was looking a the size down (the 4035) and he said it would run it but he suggested I go up a size so I did since the cutter was a larger and I wanted to do it commercially. Its a dual blade Howse like this. I would think the hardest part about handling this cutter is its weight (about 1400 lbs) not turning the spindles. The funny thing is, the 7' cutter weighed more. My experience tells me its more about knowing your machine and equipment than "is it big enough just to power through". I cut 36" tall fields with my SCAG. Its slow but I can get the job done because I know how to cut it. It certainly isn't designed to mow that.

TripleR · Nov 10, 2013

Someone posted this on another thread; may help, may not: TractorData.com - Mowing with tractors

Gary Fowler · Nov 10, 2013

irsmun said:
Again, I understand times will vary. I also cut grass professionally with a commercial zero turn. I've cut enough that I can just look at a yard and give a pretty good estimate on time. But with this I have never used it and don't have a field lying around to go test it out...or I would. So replies that give me your approximate times on your size cutter at least help me get a feel for where I am.

As for the tractor size, I went in to the dealer with the intention of buying both a tractor and this cutter. I was looking a the size down (the 4035) and he said it would run it but he suggested I go up a size so I did since the cutter was a larger and I wanted to do it commercially. Its a dual blade Howse like this. I would think the hardest part about handling this cutter is its weight (about 1400 lbs) not turning the spindles.

Except for transporting, half the weight will be on the tail wheel, so it shouldn't be problem when mowing to handle it so I wouldn't worry so much about that. Weeds will cut easily but tall grass is going to slow you down a lot with a bush hog so I would factor in that depending on the work to be down. If tall weeds are to be cut, you can run at about any speed that you can stay in the seat, but tall grass will put you back to 3 MPH or less as the thick edges of a bush hog blade are not efficient when cutting grass like your mowers are and if you go too fast in grass, you will get a bad cut and or stall the engine. I think that you are going to have to experiment with this like your lawnmowing business till you get some experience so you can look at a field and say that will take me x hours. OF course small fields = more turning and overlap so you could go down to 50% efficiency or less with small area and obstacles to go around. Many folks with large acreage will own their own tractors and mowers so I would expect that most of your work might be small lots so be prepared for that.

irsmun · Nov 10, 2013

TripleR said:
Someone posted this on another thread; may help, may not: TractorData.com - Mowing with tractors

Yep, I used that. Its awesome. I am just trying to get some real world numbers.

Haoleguy · Nov 10, 2013

Irsmun - Clearly depends on what you're cutting and the terrain you're traveling on. I would suggest starting with a conservative number based on a cost per hour you wish to achieve and then charge less if you're faster. For example if you are shooting for $50/hr start with conservative speed with a quality cut you think you can achieve. To go further if you estimate 1 acre/hr and there's 5 acres to do your quote would be $250 for the job and if you finish early, say 4 hrs, you would charge the customer $200. This strategy would allow you to set a cost ceiling for the customer and they could be pleasantly surprised by a lower cost. At the same time you get the chance to gain experience with your setup and what is achievable that benefits both you and your customer.....Gary

Chilly807 · Nov 10, 2013

Efficiency is a good point, it's easy to chew up time turning and backing. I try for a Zamboni style pattern, with as little idle time as possible.

Sean

irsmun · Nov 10, 2013

I agree with the efficiency issue. But at this point I have to assume average efficiency such as 80% on a perfectly square field with no obstacles. My original assumption was 3 acres per hour on a moderately high grass/weed mix. That seems to be a consensus. Experience with this tractor/cutter combination will get it to a science but I am simply at the disadvantage of not having that experience. I am starting with an arbitrary number of $75 per hour. My normal needs for my business are $60 per hour. I added $15 for the tractor use. Well, I guess its not totally arbitrary. Is that too high or low? There is no way to know except to hit it and learn. I don't think I'm far off though. My problem, which I brought to the forum, is a general estimate of what an 8' cutter is reasonably capable of at a normal cutting speed of 2-3 mph on a moderately high field of moderately tough material to cut. Translation: the middle ground average.

Degolyerent · Nov 10, 2013

I give a solid number to the customer before the job and when I am done I break down the numbers, I find that people want to know the cost up front. Your number of $75 an hour is a good number, I usually end with 75-90 per hour sometimes more and sometimes less, but that is what it takes to survive in the tractor business as there is a lot of unexpected and maintaince cost to tractor, cutter, trailer and truck
John

foreman Etexas · Nov 10, 2013

8ft pull-type and 64pto figure around 3/3.5acres,an HR,as stated above is pretty close,in good conditions. I use freemaptools.com" area calculator",type in your city state(may take zip),then hit the sat.view(zoom in),mark your pins(gives you acreage),cause the pasture is always smaller when you ask.

Tul01 · Nov 10, 2013

We have a 8'Howse dual spindle we use on our 100hp tractor. I think I usually average 2-3 ac/hour, mostly limited by the roughness of terrain. I have pushed it and done up to 4/hr, but it felt like I was going to tear something up by the bouncing. I do like the cutter, it takes a beating. I usually take the notches out of the blades with a grinder 1-2x /year and it will cut a little nicer. It does a nice job with only the 1 tire track being left a little longer when it stands up again. Oh yeah, keep an eye on the bolts holding the gear boxes on. Learned that the hard way- it still cuts with only 1 out of 4 bolts left in! We are away for the weekend, when I get home I will try to post what one field looks like after about 2 months.

Brent

irsmun · Nov 10, 2013

foreman Etexas said:
8ft pull-type and 64pto figure around 3/3.5acres,an HR,as stated above is pretty close,in good conditions. I use freemaptools.com" area calculator",type in your city state(may take zip),then hit the sat.view(zoom in),mark your pins(gives you acreage),cause the pasture is always smaller when you ask.

Yep. I use freemap tools all the time. I highly recommend it. I use it for accurate measuring for lawn mowing.

irsmun · Nov 10, 2013

Tul01 said:
Oh yeah, keep an eye on the bolts holding the gear boxes on. Learned that the hard way- it still cuts with only 1 out of 4 bolts left in! We are away for the weekend, when I get home I will try to post what one field looks like after about 2 months.

Brent

Oh my! Good thing you saw it before it was zero bolts. My client aim is commercial, like land or timber management tracts or land realtors. They usually pay less but they will give more volume. I also know the terrain will be rougher. I know that the bottom line is their game so I need a competitive price. My service will be impeccable as will my timeliness so I think pricing will be key to getting favor. That is why I am trying to get a good feel of what I can do with the 8'. I don't think the tractor is too small. It is on the low range of the cutter's recommendation. But a lot has to do with ground speed in realtion to whats being cut and how well its coming out from the shoot. That will keep the RPMs where they need to be so that it will cut as designed.

I also don't know if it is talking about Engine HP or PTO HP...but I really don't want to de-rail the thread on that one.

Chilly807 · Nov 10, 2013

Cutters are generally rated at pto hp. $75 seems high to me, although if it's a commercial customer they may not mind that price. I'd be more inclined to charge by the acre, I think most customers would be more comfortable with that as well. There's no way to lose money charging by the hour, unless you break something. On the other side, what one operator accomplishes in one hour may take another 2 hours, that's the variable a customer won't like.
Sean

irsmun · Nov 10, 2013

Chilly807 said:
. There's no way to lose money charging by the hour, unless you break something. On the other side, what one operator accomplishes in one hour may take another 2 hours, that's the variable a customer won't like.
Sean

Agreed. That's why I am taking the time to figure out what I'm looking at in time now. I figure on giving the customer a hard number to do the job. I will figure up the hours to acres myself and land on my price. If I'm wrong I eat it. Its invisible to the customer but they know exactly what they are paying.

As for $75 being high there is no way. Insurance, payroll, gas, maintenance, overhead, risk, and oh yeah TAXES. If I can cut someone's 10 acres in 4 hours, they hand me $300 and its done. I will likely do that only 2- 3 times a year...maybe once for some folks. A tractor payment (plus implements, gas, insurance etc.) will be considerably more than that for them. Its cheaper for me to do it. I charge $60 an hour for a grass cut with my mower. A tractor certainly merits an additional $15. This is not a hobby. Some people want cheap. That's not my client. I looking for a client who wants value. Fair price, great service, and dependable. That said, when researching pricing it seems to have a lot to do with where you are in the country. That's why my question wasn't "what should I charge?". I know what I need to make I just need to know how do an estimate for a customer and I will base that on how much I can cut in how much time.