Acres cut per hour

[Builder]

Anyone ever see a chart that combines ground speed with deck width to calculate how much acreage can be cut in an hour?
Got a finish mowing contract-about 20 acres. I usually do larger rough areas with bush hog. Would like to calculate time it will take to cut. Have to buy a flail or finish mower for the job. Would like to see what width & speed would be needed to finish it in 8 hours.

 

[Farmwithjunk]

Width of cut (as opposed to width of mower)in inches X mph divided by 100 = acres per hour (at maximum efficiency)

Deduct for time spent turning, mowing around obstructions, ect...

"Width of cut" has to reflect overlap to be anything like accurate...

This is a quick, easy way to get a close estimate.

 

[Will_C]

I remember seeing a chart like that on a website...either Scag or Exmark, or perhaps both.

Will

 

[jenkinsph]

Farmwithjunk,
That works out to be very accurate, certainly close enough to make me remember it. Thanks for the heads up.:thumbsup:

 

[Builder]

Thanks FWJ. Anyone think 4MPH is a reasonable speed mowing 12-18" tall pasture grass with a 8' finish mower behind my M-7040?

I usually only do bush hogging. When I bush hog, I go ~3MPH with an 8' bush hog through 5' tall weeds, but it leaves some sticking up here & there.

According to my calculations. I should be able to cut 3.8 acres/hour at 4MPH w/ 8' finish mower. I would reduce that to 3 acres per hour to account for turns. So I should be able to mow 20 acres of light pasture in under 8 hours with a 8' finish mower if I run at 4MPH.

Sound plauseable?
I pretty much got the mowing contract, now I gotta find a big finish mower. Flail or finish is the next step.

 

[dkjbama]

TractorData.com - Mowing with tractors
It doesn't output in acres/hr, but I've found the mowing-time calculator at this link to be useful. The HP/width graph is informative as well.

 

[Verticaltrx]

Here's another formula that I use:

(Width of cut in feet x MPH x % efficiency)/8.25

The % efficiency in this equation reflects overlap, time for turns, etc. 100% efficiency would be like mowing full width no turning, stopping, etc.

For example:

(8' x 4mph x .75)/8.25 = 2.91 ac/hr

 

[jenkinsph]

Thanks FWJ. Anyone think 4MPH is a reasonable speed mowing 12-18" tall pasture grass with a 8' finish mower behind my M-7040?

I usually only do bush hogging. When I bush hog, I go ~3MPH with an 8' bush hog through 5' tall weeds, but it leaves some sticking up here & there.

According to my calculations. I should be able to cut 3.8 acres/hour at 4MPH w/ 8' finish mower. I would reduce that to 3 acres per hour to account for turns. So I should be able to mow 20 acres of light pasture in under 8 hours with a 8' finish mower if I run at 4MPH.

Sound plauseable?
I pretty much got the mowing contract, now I gotta find a big finish mower. Flail or finish is the next step.

Reminds me of docking a boat, "Never approach the dock faster than you are willing to hit it."

I might consider going a little slower if the ground is hard to see the first cut. I am sure you can easily choose the right speed within a short time in the seat, just make sure you STAY in the seat.

 

[Builder]

Steve,

Ground is easily seen, so all is well there. I just bush hogged on Tuesday. Did about 40 acres and I'm pretty sure I was running about 2.9MPH. I'm pretty sure I could mow in 4th gear low range.
Seat belt will be buckled! :thumbsup:

 

[kco]

Here's another formula that I use:

(Width of cut in feet x MPH x % efficiency)/8.25

The % efficiency in this equation reflects overlap, time for turns, etc. 100% efficiency would be like mowing full width no turning, stopping, etc.

For example:

(8' x 4mph x .75)/8.25 = 2.91 ac/hr

That's the EXACT formula. Gotta love the English measurement system. :confused2: An acre is 1 rod (16.5 feet) by 1/2 mile or 1/2 rod (8.25 feet) by 1 mile or 43,560 sq. ft. And of course there are four rods in a chain (66') which are the width of prairie road allowances (except they are 1.5 chains in some places).

The money system used to be as much fun. I visited the UK in 1965/66 when the common coins were 1/4 pence (farthing), 1/2 pence, 1 pence, 6 pence, 1 shilling, 1/2 crown (2 shillings, 6 pence), 1 crown (five shillings), and the pound.

There were 12 pence per shilling and 20 shillings per pound.

It was a challenge figuring the value of a pocket full of change. And to make it worse, the 1 pence coin was about the largest, a copper coin about the size of a 50 cent piece or silver dollar!

To confuse things further shops sometimes priced goods in guineas, which I believe was an unofficial value of 21 shillings (i.e. 1 more shilling than a pound).:confused2:

They converted to a decimal system in 1971.