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griffinz
04-12-2008, 03:38 PM
OK,

I wanted to compute the time needed to cut my back yard... thus finding the formula needed for my mower.

I walked off the back yard using my Lufkin rolling tape measure... I guess that's what you call it.

This gave my my back yard in sq ft.

So:

SqFt of my back yard = 12768

1 sq foot = 2.29568411 ◊ 10^(-5) acre

Backyard sqft * 2.29568411 ◊ 10(-5) acre = .2931129472 (this is the total acres of the back yard)

mph of mower = 2.0

cut width = 42

acres cut per hour (at 80% efficiency) = ((mph*cutwidth)/120) so...

((2.0*42)/120) = .70 acres per hour

Time it takes to cut back yard = (back yard acres/acres per hour) so...

(.29/.70) = .42 hours to cut back yard so...

.42*60 = 25 minutes to cut back yard.

Is that right????:confused:

Now, don't ask me to cut the back yard and time it!

milsaps118
04-12-2008, 04:02 PM
You have a 42" mower that can only go 2.0 mph??? Either you have a really really bumpy backyard, or you are definitely not running at 80%. It should take you 10min TOPS to cut 12.7K sqft.

griffinz
04-12-2008, 04:12 PM
You have a 42" mower that can only go 2.0 mph??? Either you have a really really bumpy backyard, or you are definitely not running at 80%. It should take you 10min TOPS to cut 12.7K sqft.

I think it cuts at 2.5 mph... its a residential Craftsman :laugh:

milsaps118
04-12-2008, 05:31 PM
I think it cuts at 2.5 mph... its a residential Craftsman :laugh:

Well then if thats the case, 25min is about right.

Dave_005
04-12-2008, 06:11 PM
OK,

I wanted to compute the time needed to cut my back yard... thus finding the formula needed for my mower.

I walked off the back yard using my Lufkin rolling tape measure... I guess that's what you call it.

This gave my my back yard in sq ft.

So:

SqFt of my back yard = 12768

1 sq foot = 2.29568411 ◊ 10^(-5) acre

Backyard sqft * 2.29568411 ◊ 10(-5) acre = .2931129472 (this is the total acres of the back yard)

mph of mower = 2.0

cut width = 42

acres cut per hour (at 80% efficiency) = ((mph*cutwidth)/120) so...

((2.0*42)/120) = .70 acres per hour

Time it takes to cut back yard = (back yard acres/acres per hour) so...

(.29/.70) = .42 hours to cut back yard so...

.42*60 = 25 minutes to cut back yard.

Is that right????:confused:

Now, don't ask me to cut the back yard and time it!

2 MPH'S !!! Wow That is SLOW ! No Offence, but you can go faster than that with a push mower. 12,000 sq ft is a little over 1/4 acre 20 mins with a push mower and its done.