Tipping a tractor over

[Bill Allis]

Been reading the WF vs NF thread a got to wondering
if there is a formula for the amount of incline where
you get a roll over? I see guys mowing right-of-ways
and they scare me! But, they must be doing it
safely. Realizing that track width, center of
gravity, etc enter into it. Is there a formula? I
guess you could just jack up one side till it tipped
over....but that's hard on equipment!

 

[JMOR]

(quoted from post at 13:50:11 01/06/15) Been reading the WF vs NF thread a got to wondering
if there is a formula for the amount of incline where
you get a roll over? I see guys mowing right-of-ways
and they scare me! But, they must be doing it
safely. Realizing that track width, center of
gravity, etc enter into it. Is there a formula? I
guess you could just jack up one side till it tipped
over....but that's hard on equipment!

ill, I'm safe in saying, yes there is................but I don't know it. However, it will not be of much value, as there are so many variables in real life situation, such as let us say that you are near tipping point , but still OK, and then the high ground wheel drops into a small hole/rut (making you even further from tipping), but you are moving & when that wheel comes back out of that hole, you have a new found acceleration trying to rotate the tractor in the direction that it was already on the verge of tipping. Just this "little extra" and over you go.

 

[Mike(NEOhio)]

Any object tips over when its center of gravity gets outside of the base.

 

[Sean in PA]

My '73 4000 ag chassis started life as a highway mower. It has an inclinometer (sp?) installed on the tin in front of the instrument cluster. It is basically just a flat piece of sheet metal that looks like an upside down T with another piece of sheet metal cut to look like an arrow hanging from the top of the inverted T by a pivot pin. So no matter how the tractor is tilted side to side the arrow always points down, and comparing the arrow to the side arms at the bottom of the inverted T shows you how much you are leaning. I've never had the tractor angled more than about 15 degrees sideways, and that puts the arrow about 3/4 of the way out to the end of the arm of the T It looks like all of the way out would probably be around 20 degrees or so, but I've never actually measured it. From what I've felt when I was at 15 degrees, I don't think I would ever want to go past 20 degrees.

I regularly take my John Deere X500 garden tractor over to about 25 degrees or so when I'm mowing the drainage ditch by the road at the front of my property, but that is with a lot of body english on my part leaning toward the uphill side, plus a lot of pucker factor thrown in.

 

[Kirk-NJ]

I remember reading some post about tests they did on percent of incline, rate of speed and angle of turn for tipping on this sight a couple of years ago. Do a search and maybe it will come up.

Kirk

 

[cdmn]

If you are carrying anything in the front-end loader bucket, you are a lot closer to tipping over. Even if you are on level ground, and taking a turn at much speed, if the inner wheel hits a block of wood in the grass, over you go.
Many people have lived to tell about it because the tractor doesn't go totally upside down, but some do. My dad leapt off when the Farmall flipped over, but he was lucky it missed him. Some
would freeze up and get crushed.

 

[Bill Allis]

Sean, Your incline-o-meter sounds good. You could probably rig some kind of water level using a piece of clear tubing.

Sure agree with having a loaded bucket in the air and it's effect. However a loaded bucket nearly on the ground would be helpful in prevented a roll over. Again we are back to center of gravity and the difficulty in computing it. A tall loaded tire would have the same effect. 38 inch loaded tires would be more prone to roll over than 28 inch tires.

 

[Sean in PA]

If the left and right are filled the same, then taller loaded tires would only make a negligible difference in terms of roll over potential. Since there's just as much additional weight on the uphill side of the tractor the small amount of excess that would be outside of the wheel base on the downhill side shouldn't shift the center of gravity by that much. If you were going to roll it in a certain situation with loaded 38's then I wouldn't want to be in the same situation with loaded 28's either.

 

[tim(in)]

After watching the youtube videos of guys in europe making hay on mountains you would think our tractors should NEVER roll over but they do and often on seemingly flat ground.I was always leary of rollovers. nephew did it on my original wd allis chalmers once being a big shot!

 

[Geo-TH,In]

When I was a kid, loading logs on truck with a NF Farmall, I flipped the tractor. Lucky the back wheel came to rest on a log instead of me.

My terramite backhoe has what angles you should avoid. As for a formula, I would think the wheelbase has something to do with it. Also if you are lifting something with a loader. My back wheels on terramite are only 4 ft outside to outside. I have to be very careful if I run a back wheel up on a rock. Good reason to have a very good roll cage and a seat belt, not just a roll bar that might cut you in half.

I've even been told of a guy who was dragging something with his AC WD. Whatever he was pulling hit a tree stump and flipped the tractor over on him. He was lucky too.

Best thing is use good judgement. Wider wheel base it good too. Avoid steep inclines.

 

[Texasmark1]

I use a fishing weight and piece of string. Since the tractor weighs 10+x what I do, I hold the string just over the steering wheel. If the weight is inside the lower tread on the downhill side, I'm good to go AS LONG AS YOU KEEP IT SLOW AND DON'T BOUNCE THE UPHILL TRACTOR REAR TIRE ON A ROCK OR RAVINE.

Mark

 

[paul]

You are looking for a scientific number, and this is much more of an art, seat of the pants feel.

Rough Terran, cornering, speed, all pray a roll.

You just need to start slow and level, and work your way up, develop a feel for it.

Hit a gopher mound, have a tire lose 10lbs of pressure, turn a corner, pop th clutch, etc and your formula just changed totally.....

Paul

 

[JMOR]

(quoted from post at 02:02:31 01/09/15) You are looking for a scientific number, and this is much more of an art, seat of the pants feel.

Rough Terran, cornering, speed, all pray a roll.

You just need to start slow and level, and work your way up, develop a feel for it.

Hit a gopher mound, have a tire lose 10lbs of pressure, turn a corner, pop th clutch, etc and your formula just changed totally.....

Paul

have heard for years, that if you sneak up on them while they are asleep, that you can tip them over with one finger, narrow or wide!

 

[NoNewParts]

like the guys say, it's just impossible to figure in every situation.
I got in trouble recently using my boxblade on a flat ground curve,
changing the water drainage grade.
turned just right, shallow, gradual dip, everything just right.
left front 3 feet in the air and climbing...impossible...but here we are. Took a lot of body leaning and a 20 point, inch at a time back and forth to get out upright.

Normally, us old guys can just say "listen to that inner voice"
ya know, the one saying you are going to die here LOL
But, this is with a lifetime of growing up before modern safety craziness.
We grew up testing the limits of every toy with an engine and have the scars and mended bones to show for it.
So, the inner voice is well-tuned.
It starts yelling danger....we listen.