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Specop_007
Silver Member
Unfortunately no. Think of a ditch on a road. Its not long enough to attack on an up and down length.
At what point does a CUT tip over?
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Unfortunately no. Think of a ditch on a road. Its not long enough to attack on an up and down length.
Most tractors with ag tires will slide before they tip over (as I have tested on my own property). That's one thing that most operators don't know about tire designs. But that was my line of work, too.
But, you can figure it out with a few simple steps. You need a tilt table on which to park your tractor with a simulated dummy on it (use your BIL
). You also need a scale capable of measuring the restraint force needed to keep the table from flopping over when you set the table at various angles (not very large ones either). When you have a dozen or so meaurements at lets say 2 - 5 degree increments you have enough data. Did I mention that you need to chain the tractor down vertically and laterally so it is locked in place. We used wood blocks from the table base up to the frame to hold it in an exactly controlled position. Using the data, compute the intercept of tilt angle when the scale data would go to zero (which it does at incipient rollover). From this you can also compute the center of gravity height, and this dimension gives you the info you need to figure out on what sidehill angle and extra sideforce it would take to roll it over. Yes in reality the tires are turning, you may be steering it, you may lean out of the turn, the earth is moving, the moon's gravity is pulling up on you and the sun is moving in the Milky Way. But, you will have a pretty darned close angle to stay away from. Yes you can get closer by steering the wheels and filling the fuel tank and mounting wights higher on the weight bar, but this tilt table technique is in standard use throughout the industry. We used strain gaged chains to tell us when the restraint loads went to zero (indicating rollover). but that's more info that you don't need to get PFC.
That's how you can tell on your particular machine. Like I said before, most tractors will slide down a hill on grass if presented with a large angle. If you trip it though, the angle would be lower. That means, a quick steer angle, hit a rut, jump off the seat, raise the loader, hit a bump, you get the idea...
5, 4, 3, 2, 1, 0. Now all the makebelieve x-spurts can jump in.
But, you can figure it out with a few simple steps. You need a tilt table on which to park your tractor with a simulated dummy on it (use your BIL
). You also need a scale capable of measuring the restraint force needed to keep the table from flopping over when you set the table at various angles (not very large ones either). When you have a dozen or so meaurements at lets say 2 - 5 degree increments you have enough data. Did I mention that you need to chain the tractor down vertically and laterally so it is locked in place. We used wood blocks from the table base up to the frame to hold it in an exactly controlled position. Using the data, compute the intercept of tilt angle when the scale data would go to zero (which it does at incipient rollover). From this you can also compute the center of gravity height, and this dimension gives you the info you need to figure out on what sidehill angle and extra sideforce it would take to roll it over. Yes in reality the tires are turning, you may be steering it, you may lean out of the turn, the earth is moving, the moon's gravity is pulling up on you and the sun is moving in the Milky Way. But, you will have a pretty darned close angle to stay away from. Yes you can get closer by steering the wheels and filling the fuel tank and mounting wights higher on the weight bar, but this tilt table technique is in standard use throughout the industry. We used strain gaged chains to tell us when the restraint loads went to zero (indicating rollover). but that's more info that you don't need to get PFC. That's how you can tell on your particular machine. Like I said before, most tractors will slide down a hill on grass if presented with a large angle. If you trip it though, the angle would be lower. That means, a quick steer angle, hit a rut, jump off the seat, raise the loader, hit a bump, you get the idea...
5, 4, 3, 2, 1, 0. Now all the makebelieve x-spurts can jump in.
Steve C
Platinum Member
What are you? Some kind of girly man? Afraid of being crushed to death by a diesel and oil filled cast iron weight????
Well I don't blame you, it is good thinking. If you have spent your youth riding dirt bikes you have a good feeling for when you are about to tip over. I would think that most people with tractors have never had that experienc.
To get the information you are looking for you would have to model the c.g of the tractor against a slope. I doubt that it would be helpfull, you just have to go there, with protection! Get some roll over protection and play with it. I have had my Farmpro standing almost on end but have felt very safe because I know what it will do. I was more concerned about the oil pick up.!!!
I think something to consider here is the difference between a static rollover angle and a dynamic rollover angle. (this comes from helicopter aerodynamics but it applies to any vehicle)
Small bumps or changes in the side hill angle will develop a roll rate (a momentum if you will) in which the vehicle, in this case a tractor, will tip over at some angle LESS than the static rollover angle, which was discussed above with the tilt table. The faster you go, the more that the forward motion can be converted (or ramped) into a rolling motion. Hence a gauge is worthless unless you'r3 dead stopped, and the slower you go the better. Also, if your tires are slipping sideways, that sideways motion will be converted into that same rolling motion when the sideways slipping tire eventually snags on something.
Small bumps or changes in the side hill angle will develop a roll rate (a momentum if you will) in which the vehicle, in this case a tractor, will tip over at some angle LESS than the static rollover angle, which was discussed above with the tilt table. The faster you go, the more that the forward motion can be converted (or ramped) into a rolling motion. Hence a gauge is worthless unless you'r3 dead stopped, and the slower you go the better. Also, if your tires are slipping sideways, that sideways motion will be converted into that same rolling motion when the sideways slipping tire eventually snags on something.
dmccarty
Super Star Member
I have and use a Tiltmeter on my tractor. There certainly is time to glance over at the Tiltmeter while watching the ground and where you are driving. I do it all of the time. I hope people watch their engine RPM, temps and fuel gauges. Looking at the Tiltmeter is no different.
The Tiltmeter is not going to see nor tell you there is a stump, rock, log, or hole that you are about to hit that will turn you over but it will tell you that you the tractor angle. You then decide if that angle is safe or not. A single small rock or hole can be enough to take you quickly from a safe angle to a roll over. The operator has to decide what is a safe operation angle for the conditions.
Much more than 10 degrees is not fun. At some point after using the Tiltmeter you get a feel for the angles. I have a ditch that I mow. It starts up very shallow but as it works its way up hill the steepness increases. There is a certain spot where I have to stop mowing with my tires in the ditch. BUT that spot can change over time and it has.
I mow in low range first gear so I am just crawling along and I watch the Tiltmeter. The tractor starts out at 5 degrees and I get out of the ditch between 10-15.
Mowing a ditch or bank you have to be concerned with the dirt moving out from under the tractor as well.
With my tractor and implements held low to the ground I don't think the tractor will flip at 20 degrees but since I don't have a tilt table that is just a guess. I don't get near 20 degrees if I can help it. If I do I quickly get the tractor back to something safer. I seldom get past 10 or so with maybe 15 in that ditch. Maybe.
Later,
Dan
The Tiltmeter is not going to see nor tell you there is a stump, rock, log, or hole that you are about to hit that will turn you over but it will tell you that you the tractor angle. You then decide if that angle is safe or not. A single small rock or hole can be enough to take you quickly from a safe angle to a roll over. The operator has to decide what is a safe operation angle for the conditions.
Much more than 10 degrees is not fun. At some point after using the Tiltmeter you get a feel for the angles. I have a ditch that I mow. It starts up very shallow but as it works its way up hill the steepness increases. There is a certain spot where I have to stop mowing with my tires in the ditch. BUT that spot can change over time and it has.
I mow in low range first gear so I am just crawling along and I watch the Tiltmeter. The tractor starts out at 5 degrees and I get out of the ditch between 10-15.
Mowing a ditch or bank you have to be concerned with the dirt moving out from under the tractor as well.
With my tractor and implements held low to the ground I don't think the tractor will flip at 20 degrees but since I don't have a tilt table that is just a guess.
I don't get near 20 degrees if I can help it. If I do I quickly get the tractor back to something safer. I seldom get past 10 or so with maybe 15 in that ditch. Maybe.Later,
Dan
woodlandfarms
Super Member
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As a side note, there are ROPS you can buy for most any tractor. I don't know yours, but given your goals it sounds like a good investment in your future.
Carl
Carl
MarkV
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For me 15 degrees is about the stopping point. Are your tires filled with a liquid? It helps with stability a lot.
MarkV
MarkV
OP
Specop_007
Silver Member
Its a valid point, but frankly an expense I dont want. I just avoid mowing those areas, which cuts down on my tractor time and that aint a bad thing!