Slopes and tractor tilt

[smiley]

I just printed out the photo of the Aebi tractor and checked the angle. Using the pole in the background as a reference which should be verticle but is very slightly off, probably from the camera being tilted slightly, but close enough to show that the bottom edge of the photo is nearly horizontal. By measuring or with a protractor, you will find that the mower is actually sloping more than 45 degrees (100%) which I think is caused by the obvious crabbing of the tractor, making the top of the mower run further back than the lower side. I realize that perspective and not viewing from head on will make some difference but not a great deal. At any rate it's a lot more than 40% and the only thing keeping that tractor upright is a very wide stance and very low center of gravity. As I mentioned before, I would even be careful with a crawler on a slope like that.
As a side note, HF has a slope meter with magnetic base for $4.99, so if you want a cheap check on your slopes, pick one up and set it up with your tractor on a level area then go see at what degree the pucker factor starts.

 

[JWR]

The garden tractor at 40% isn't exactly what I'd call safe. Doable with caution sure but if you find a hole that use to have tree stump in it you suddenly you pick up 10 degrees. 40% is about 22 degrees, tack on 5 or 10 degrees for safety and you are talking about a 50-60% slope. See Slope - Degree, Gradient and Grade Converter for a nice table that goes both ways. I think their ad is correct, 40% slope is all I'd want the liability for. 40 degrees equals 84% slope would you want the liability for that? Let someone take it steeper if they think they can but I wouldn't call it safe for advertising purposes. What does JD advertise as safe for a garden tractor?

Since 40 % is far less steep than 40 degrees (as you say it is more like 22 degrees) the Aebi advertisement made a huge error in saying percent when surely they meant degrees. Advertising that they readily handle 40 percent slopes is the same as advertising that "we do nothing special and have no claim to fame." Simply foolish and obviously an inadvertant mistake.

No tractor manufacturer would advertise handling a 40 percent slope because everyone can do that.

Rare few prominent tractor manufacturers ever advertise what amount of slope their machines would handle because of liability considerations in this outrageously litigation-prone society. The only ones to advertise that are ones with very unusuable capabilities, capablities that are their "family jewels" or key features such as Aebi. That does not apply to John Deere, Massey Ferguson or Kubota. You will never see such an ad from one of them.

The point is, degrees and percent slope are drastically different if we care anything at all about even approximate accuracy.

 

[JWR]

Guys, I had to post this.....
I ordered and installed an "inclinenometer" on my Kubota last week. The slopes that had initally concerned me are only 15%. (I had gotten used to them) The ones that made me pucker are 25% and MUST be taken in "turtle and 1st gear". A few times I would sink in a hole and it would go to 30% where I would immediately do the down hill steer manuever. I'm using % because I have no DEGREE key. Now that it is installed I will recommend it to everyone.....it's definately an asset and a tool.:thumbsup:

Agree with most of what you said ... BUT GOOD GRIEF !! "Using the % key because you don't have a degree key" is equivalent to saying you don't care if a comment refers to 40 degrees or 22 degrees (since 40 percent slopes are roughly 22 degree slopes.) I originally thought you were just joking. Worst case you can spell out degrees and percent as I just did above.

By the way, there was a great post a week or two ago that pointed to the Grade (slope) - Wikipedia, the free encyclopedia website. This has the best comparison I have seen between percent and degree of slope. Has the formulas, the definitions,etc. too. For those less math oriented, that graph that shows degrees overlaid on top of Percent slope is a terrific tool/illustration.

 

[SPYDERLK]

40% vs 40* slope may be adequate in our context. Or copy the symbol from a word doc: °°°°°°°°°°°°°°°°°°°°°° °°°°°
larry

 

[wannabe20]

I hope to be able to get back to this post, trying to drop some bread crumbs. I love what you say here. Thank you for posting!

 

[Garandman]

From Army field manula.

The pace method is a quick way to estimate percent of slope. Determine, accurately, the height and pace of each soldier for each member of a recon team before using this method. As a rule of thumb, the eye level of the average soldier is 1.75 meters above the ground. The pace of the average soldier is 0.75 meter.

Perform the following procedures for the pace method:

Stand at the bottom of the slope with head and eyes level.
Sight a spot on the slope. This spot should be easily identifiable. If it is not, another member of the team should go forward to mark the location.
Walk forward and stand on the marked spot. Record the number of paces. Repeat this procedure until you reach the top of the slope (estimate fractions of an eye level).
Compute the vertical distance by multiplying the number of sightings by the eye-level height (1.75 meters). Compute the horizontal distance by totaling the number of paces and converting them to meters by multiplying by 0.75 (or the known pace-to-meter conversion factor).
Calculate the percent of slope by substituting the values into the percent-of-slope formula (see Figure 5-9). Because this method considers horizontal ground distance and incline distance as equal, you can obtain reasonable accuracy only for slopes less than 30 percent. This method requires practice to achieve acceptable accuracy. A line level and string can be used to train this method.

 

[Xfaxman]

,,,,

 

[JWR]

View attachment 395207 ,,,, View attachment 395208

Yup, that's the right stuff and it very graphically shows the (drastic) difference between percent slope versus degrees of slope quotations. I cannot imagine quantitative discussion with basic physics principles in play that could ignore degrees versus %.

 

[Garandman]

Army planners expect vehicles to be slowed by any slope greater than 7%.

 

[SPYDERLK]

So I have often joked with my friends that "surely can't be the dumbest person ever to try this".

It appears that amongst those there on TBN "I am." I am a believer that following the manual will save me $250 and the time associated with an insurance claim.

Straight up and straight down steep inclines always facing down.

If you want to add stability put several hundred pounds under you tractor on a rail and pulley system such that you can move the weight from 24-36" outboard on either side of the tractor. (Place the weight on the up hill side.) Assuming you are transversing along the side of the hill.

~Kevin

:thumbsup: ... A system to pump mercury where weight is needed could be quite sanitary and very effective. The trick would be making the system secure against damage. ... And paying for the mercury.