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i'd like to see exactly how far my truck can be pushed sideways before rollover. Can any one suggest how to safely do this in a controlled environment and what gear would be needed?
no smart arse remarks required for this one
i was thinking maybe a couple of reeeely big trees, some handwinches and some belay straps to a high point on an adjacent trees to hold it when it decides to finally go over.
Hey man, i have seen footage from a docko, that had an old cj jeep with a wheel mounted on both sides of the body, doing a swerv test on an ex-air field, they were remote controlled doing 60kph then swerve, testing a roll-over will generally have a speed of some sort, slow or fast i would imagine it will affect your results, as i have see in person a Aussie racing car flip on a race track going sideways.
I think land rovers were designed around the 45 deg mark, correct me if i'm wrong, that would be a good angle to go for, your suggestion sounds ok, just watch that the wheels don't slip when near its balance point.
Some one from the site had an MK? patrol, a heap of mattresses from curbside collection. Stacked the mattresses next to the patrol and jacked it up until they could push it over by hand. Might be an idea anyway...
rollover from what situation? high speed manouevering on the road, off a ledge, off a rock, what? Different things can cause a vehicle to roll over, sometimes just the angle of the vehicle, other times a combination of the wrong speed and a bump et c etc.
Way too many variables can come into play to assume you can work out when it will rollover. I'd imagine you can try with a forklift and some sort of strapping etc to anchor it, but not really sure what the accuracy or relevance of finding out how much of an angle takes it to rollover in a carpark compared to actual 4wding would be.
i know what you're saying about the infinite number of variables. i'm thinking more about the many times i have been slooooowly trying to get over an obstacle or along a trail and have had to back off because i'm a skirt and the truck isn't the most confidence inspiring (troopy).
I often wonder if it's just me being a sook, and if the truck had lots left. So yes, while there are a number of variables including speed and loading etc, it would help to get a feel for where the line is.
The easiest and safest way is to connect your winch to a snatch block on a tree off to one side and then double line it back to a high point on your truck. Do this on a slope where the is some sort of ramp or stump or rock. Then simply drive a front wheel up on the ramp, making sure you have the winch rope just off the ground but without too much tension. You want to have the rope just tight enough to give you confidence that the truck wont fall completely over when it gets light. This way you can winch in when you get nervous.
correct me if im wrong, ive seen a table where they strap a car onto chain it down and it lifts on one side, and they are able to work out the roll over angle, but im not sure if they are in australia or even would be cost effective.
You can work out where your centre of gravity is by weighing each wheel whilst the vehicle is flat, then you tilt it sideways by x degrees forward and sidewards and using some mathematical formula you can work out where your cog is relative to the wheels.
That would be the most usefull information you can get accurately, where you will rollover in a dynamic (moving) situation is dependant on lateral and longditudal forces and also what your suspension is doing and what angle the vehicle is on.
[quote="toughnut"] You want to have the rope just tight enough to give you confidence that the truck wont fall completely over when it gets light. This way you can winch in when you get nervous. [/quote]
what i did was drive a rut that was just wide enough for the car to lean on one side when it went over so it only flopped like 4" and i could easily drive out of it.
its all about seat time still ... get the confidence up to drive over that ledge and lift rear wheels
H( * )( * )NZ loves B( * )( * )BIES
if a fat lady falls in the forest do the trees laugh?
[quote="RUFF"]although i didnt mean to, i squealed like a girl :armsup:[/quote]
toughnut wrote:The easiest and safest way is to connect your winch to a snatch block on a tree off to one side and then double line it back to a high point on your truck. Do this on a slope where the is some sort of ramp or stump or rock. Then simply drive a front wheel up on the ramp, making sure you have the winch rope just off the ground but without too much tension. You want to have the rope just tight enough to give you confidence that the truck wont fall completely over when it gets light. This way you can winch in when you get nervous.
Whilst doing this I would also recommend with securing the lowest part of the car, possibly sliders to a tree to prevent the tyres from slipping towards the tree with the winch cable.
toughnut wrote:The easiest and safest way is to connect your winch to a snatch block on a tree off to one side and then double line it back to a high point on your truck. Do this on a slope where the is some sort of ramp or stump or rock. Then simply drive a front wheel up on the ramp, making sure you have the winch rope just off the ground but without too much tension. You want to have the rope just tight enough to give you confidence that the truck wont fall completely over when it gets light. This way you can winch in when you get nervous.
Whilst doing this I would also recommend with securing the lowest part of the car, possibly sliders to a tree to prevent the tyres from slipping towards the tree with the winch cable.
Steve
You don't need to if it is on a bit of a slope or if you are driving a ramp. You only use the winch cable for a safety strap. If you put tension on it you won't get an acurate experiment.
toughnut wrote:This would only work if you didn't have suspension.
Gribble is correct, the suspension will only react to the force implied upon it which inturn acts upon the ground.
The place I used to work did tilt tests on various trucks, buses etc. They have a tilt table that they drive the vehicle up on and a crane lifts one side of the table, there is a large pivot on the other side. They would chain down the axles so they had about 50mm of movement then lift the vehicle until the high side started to leave the table. From here they would measure the angle and repeat on the other side. Using this they can work out the roll centre. They also repeat the test with the suspension blocked up to take out any body roll thus calculating the CoG.
toughnut wrote:This would only work if you didn't have suspension.
Gribble is correct, the suspension will only react to the force implied upon it which inturn acts upon the ground.
The place I used to work did tilt tests on various trucks, buses etc. They have a tilt table that they drive the vehicle up on and a crane lifts one side of the table, there is a large pivot on the other side. They would chain down the axles so they had about 50mm of movement then lift the vehicle until the high side started to leave the table. From here they would measure the angle and repeat on the other side. Using this they can work out the roll centre. They also repeat the test with the suspension blocked up to take out any body roll thus calculating the CoG.
I stand by what I said. This is good for C of G but the original post is about roll center and therefore C of G calculations would not give you the roll center angle that Milo is looking for.
phippsy wrote:Some one from the site had an MK? patrol, a heap of mattresses from curbside collection. Stacked the mattresses next to the patrol and jacked it up until they could push it over by hand. Might be an idea anyway...
Heathx4 in the uni dormitory carpark. Pushed his MQ over on matresses. If someone can host i have pic. Remember that a car may be stable at one point with no load on, but as the motor torque loads the suspension can then flip. It all depends on the situation.
Layto....
[quote="v840"]Just between me and you, I actually really dig the Megatwon, but if anyone asks, I'm going to shitcan it as much as possible! :D[/quote]
email it to me at rockcrawler@cliffhanger.com and i will post it. was there any damage to the car? was it a controlled roll or did he literally just push/pull it over. would have been funny to see for a passer by
I have a Troopy as well. About 6 weeks ago, before a Toolangi drive I was gonna do the same thing but we didn't get time. I fitted an inclinometer as I too am paranoid about putting it on it's side. My biggest dilemma was what to tie the strap onto to limit how far it leans, we thought we'd chuck a strap through the side windows and run it around the gargo barrier as well as the pillars. We intended to use a couple of hi-lift jacks to slowly tip it over.
Please let us know at what angle it tips if you end up trying this, mine has a 3" lift and 35" so it'd go over before yours.
Stu
love that little animation. cracks me up every time i see it.
should be doing this when i get home, as i have lots of BIIIG trees near home to use as anchors.
Mine is three inches lifted too, but i have a long range tank which i will have to keep empty as i think when full it would actually help the situation.
did you have a look at the pics i chopped in the yota forum for a troopie soft top ? might be a good idea for when yours finally succumbs to the turret rust blues.
rockcrawler31 wrote:
did you have a look at the pics i chopped in the yota forum for a troopie soft top ? might be a good idea for when yours finally succumbs to the turret rust blues.
I was reading something about a cutting the lid off, I'll have a look.
Cool, my troopy has turned into a ute!
It's only a bit over a year old so I'll wait a while I think.
Last edited by stoo2 on Mon Jul 03, 2006 2:58 pm, edited 1 time in total.
love that little animation. cracks me up every time i see it.
should be doing this when i get home, as i have lots of BIIIG trees near home to use as anchors.
Mine is three inches lifted too, but i have a long range tank which i will have to keep empty as i think when full it would actually help the situation.
did you have a look at the pics i chopped in the yota forum for a troopie soft top ? might be a good idea for when yours finally succumbs to the turret rust blues.
Make sure you post pics of it going over this arvo!
I think i'd tray mine, with a troopy-shaped canopy. That way the cab wouldn't look too high. All the chopped troopy's i've seen look a bit funny cos of the massive cab.
i'm getting a more solid idea as to how i am going to do this.
i going to park alongside a tree that is about 1 and a bit metres thick about 4 metres from the base.
the belay will be a snatch strap or tree protector around the B pillar and rearmost pillar in a triangle shape over the roof towards the tree. a winch cable will be attatched to the middle of the strap and will go to a pully 4 metres up, then to another truck with the winch, butted up against another tree or chained from behind for safety.
the offside wheels will be in a dug channel to locate the tyres, and a chain wrapped around the axles in case the vehicle has to be anchored at the base.
the truck will be progressively jacked up and blocked to tip it over.
either that or i will find a tilt towie to let me drive it on sideways and use his winch as a control. a la the tilting platform mentioned earlier. anyone with a tilt tray?
what do you actually hope to prove. Tipping a vehicle sideways in a controlleed mannner on a flat surface means nothing when you are trying to climb a slippery side slope, or driving through a rutted section of track. You can tip a car over alot easier than you think but sometimes you can also lean a car over alot more than you think. What it comes down to is you need to know when your truck feels like going over. This can only be gained from real time driving experience.
going sideways.
