The HP/Cutter Width Rule-of-Thumb

[smstonypoint]

First, my rationale for this post. It's raining so I can't work outside and I fear that the Missus will assign me household chores if I do not appear busy at the keyboard.

The rule-of-thumb that each foot of rotary cutter width requires 5 tractor HP is often cited here. I thought I would test the rule-of-thumb against a manufacturer's recommended minimum HP requirements. I selected Woods rotary cutters for the test for no particular reason, and used the information from the Woods Web site to construct the attached chart. *

Woods Equipment Company


The cutters with black symbols are 3PH-mounted models and those with red symbols are either pull or semi-mounted models. When a model was available as either a 3PH mounted or pull type, I used the pull model data.

How does the rule-of-thumb perform? You be the judge, but I would recommend the rule-of-thumb only as a very rough first approximation.

Steve

* I'm not bored enough to expand the chart to include other manufacturers.

 

[jake98]

I have a 5' on a 25 hp Kioti, and a 17 hp walk behind with 3' cut, both work good. I don't want to do the dishes either.

 

[Builder]

I have a 70 HP tractor and an 8' JD MX-8 semi mount. Runs the mower like it's not even back there-through very heavy field grass.

Will get a 12' folding batwing someday.

 

[clemsonfor]

First, my rationale for this post. It's raining so I can't work outside and I fear that the Missus will assign me household chores if I do not appear busy at the keyboard.

The rule-of-thumb that each foot of rotary cutter width requires 5 tractor HP is often cited here. I thought I would test the rule-of-thumb against a manufacturer's recommended minimum HP requirements. I selected Woods rotary cutters for the test for no particular reason, and used the information from the Woods Web site to construct the attached chart. *

Woods Equipment Company


The cutters with black symbols are 3PH-mounted models and those with red symbols are either pull or semi-mounted models. When a model was available as either a 3PH mounted or pull type, I used the pull model data.


How does the rule-of-thumb perform? You be the judge, but I would recommend the rule-of-thumb only as a very rough first approximation.

Steve

* I'm not bored enough to expand the chart to include other manufacturers.

Can tell you were a statistics/econ professor. Sorry i just thought it was funny and had to comment

 

[smstonypoint]

Can tell you were a statistics/econ professor. Sorry i just thought it was funny and had to comment

I was going to test HO: alpha = 0, beta =5 versus the alternative that at least one equality fails and report the results. However, I might be banished from TBN if I do so.

Steve

 

[Chilly807]

You really DO have too much time on your hands... let this be a lesson, next time buy a tractor with a cab so you can mow in the rain.


Sean