One Link and 3Link front suspension (homemade)

[bill van snorkle]

Those are the ones I want for the Disco. Fedima makes them in both 9.00R16 and 35x10.5R16 marking, but it´s the same tyre.

This will be a selectable version of that

Good treads also http://forums.lr4x4.com/index.php?showtopic=27817 and http://www.pirate4x4.com/forum/land-rover/816718-diy-3-link-front-suspension-rrc.html

There is a bit of a problem with that hinged hockey stick arrangement in that the 2 bushings on the R/H/S are having to\ do the job of 4 bushings to control front axle tramp on gradients where traction alternates between good and poor. Some also claim that the left front suspension unloads on offcamber descents leading to a roll over although I never really experienced that phenominen on the RangeRover based hybrid I inherited that has a hinged arm fitted.

[simonr]

I built a setup with the bendy hockey stick as above and found that the asymmetry it gave in the steering due to camber change made it hard to predict how it was going to behave at the limits of stability. It didn't cause me to roll over - but gave a few frightening moments!

I then made a setup with a pair of cross connected hydraulic rams which controlled the bending of both hockey sticks - allowing articulation but not axle roll. This worked very well - except - with the limits of size and placement of the rams, it kept blowing the seals because the pressures were too high. The seals were rated at over 6000psi. It was after that that I started experimenting with height adjustable suspension instead.

Dan - wheels or tyres? The tyres were off the twist in the middle buggy and the wheels were donated by Nick Watts.

Although the winch looks low, the cable pulls directly in line with the top of the chassis rails ans is well above the bottom of the sump etc. It has an 80 deg approach angle so it's not as if the winch is going to get caught up on anything.

It weighs in at 1205kg as it stands - which is a lot heavier than I wanted as the twist in the middle truck was only 970kg. To get even that, I stripped every bit of carpet, seat & soundproofing out of it and fitted blow molded polypropylene seats which weigh about 8kg each (From Whitbred).

Si

[dirtydiesel]

Dan - wheels or tyres? The tyres were off the twist in the middle buggy and the wheels were donated by Nick Watts.

Although the winch looks low, the cable pulls directly in line with the top of the chassis rails ans is well above the bottom of the sump etc. It has an 80 deg approach angle so it's not as if the winch is going to get caught up on anything.

It weighs in at 1205kg as it stands - which is a lot heavier than I wanted as the twist in the middle truck was only 970kg. To get even that, I stripped every bit of carpet, seat & soundproofing out of it and fitted blow molded polypropylene seats which weigh about 8kg each (From Whitbred).

Si

I collected the wheels for Nick many moons ago. I wonder if its the body lift thats making the winch looks low.

Ours was fairly stripped out, i don't think i could have got it much lighter without a total re-think, the air shocks on yours probably save getting on for 40kg a corner

[simon_s]

Please stop posting up pictures of awesome Jimnys. This is a LR forum don't you know. Kthxbye.

Between the two of you you've built my two favourite Jimnys in the UK.

[o_teunico]

I suspect that the radious arm anchor points could be moved much closer together and mounted on the crossmember to get more flex. (2 point rubber version of 1 link) Dave Lloyd's truck does have the anchors closer together and under the chassis rails.

What´s the best way of doing that: A or B? (radius arms heated in forge and bent)

[bill van snorkle]

What are the chances of bending some hockey sticks inwards at the axle end bringing the chassis ends together and making a triangle out of tube they could screw/weld into the two ends of and use one of Simons X joints with the ball threading into the other point with the bush case bolted to a modded gearbox x member.

Is this impossible to package due to sump/ prop clearances or would a solid bar prop and cut the rear corners off the sump sort this? You could skin the underside of the hockey sticks going under the axle and trackrod for a serious skid plate/ track rod protected/ sump gaurd.

I was hoping to have a play with this idea next tune I have a rolling chassis but its just not happening.

Will.

What´s the best way of doing that: A or B? (radius arms heated in forge and bent)

I don't know about the material quality of later hockey sticks, but the RangeRover classic ones were nice to work with.Even cold you could virtually tie them in knots without the metal cracking.

[plasticbadger]

The pictures above would work ok, but I'd concerned about the lack of control offered by the chassis end bushings. A solid single joint as used by dirty diesel previously would be the way to go.

The build thread somehow disappeared, but I built a couple of three link front trucks. A disco and a rangie with landcruiser 80 axles.

I found packaging the three link was easy, but it had some design flaws. It drove well, but I ended up with too much anti dive, plus too much lift on the lighter engined rangie, causing issues with roll and steering geometry. I also under built the brackets and joints, using only 3/4" rose joints throughout. The big advantage of the front 3 link was the balanced flex and articulation front and rear made the trucks very stable to drive.

[Team Idris]

I don't see the radious arm double bend gains anything, as the bushes will have to do some twisting anyway. And maybe if the anchor points are closer than say 12" you might as well go with a single ball?

Although single link has flex, it's hard to get away from the fact that standard, or 3 link, feeds the shock load of a wheel-impact direct to a chasis rail through a rubber bush and in a direct line. ( I do admire 4 link though, parralel or two triangles).

One of my concearns on flex was the way an 80" landy got around the place being front heavy. Lifting a back wheel was never a major issue as the front axel pulled you through

So then I was thinking that having the majority of the flex was better on the back. But I was still faced with the fact that the Bobcats got every where with no flex at all? And in the end I personally would rather wave a wheel than loose stability.If nothing else, I don't have to re-learn the trucks behaviour.

But my outside-the-box front flex fix was going along the lines of a third radious arm in the middle of the axel. Simple enough on fabrication, and easily reversed if it didn't work well or just for a long road trip.The outers would have the end bolts removed and take end loads, the new inner would stop the axel twist. What I wasnt sure about was how much fore and aft movement this third radious arm would need at the anchor?

I'm not saying it was going to be awsome, but worth a think as a wierd 3 link

[dirtyninety]

DirtyDiesel, you typed this almost 7 years ago, I didnt understand it then, and I'm still struggling. Care to enlighten?

Eg: on a conventional front suspension setup the torque reaction is the same on both sides of the axle so that when the power is applied the rotation of the prop (transferring the torque to the wheels) will always lighten the wheel on the n/s (o/s on the rear) this means that under power one wheel will always have more mechanical grip than the other, by altering the separation of the remaining upper link you can almost completely remove this.

[o_teunico]

But my outside-the-box front flex fix was going along the lines of a third radious arm in the middle of the axel. Simple enough on fabrication, and easily reversed if it didn't work well or just for a long road trip.The outers would have the end bolts removed and take end loads, the new inner would stop the axel twist. What I wasnt sure about was how much fore and aft movement this third radious arm would need at the anchor?

I'm not saying it was going to be awsome, but worth a think as a wierd 3 link

Somethig like this? I like that idea.

[bill van snorkle]

DirtyDiesel, you typed this almost 7 years ago, I didnt understand it then, and I'm still struggling. Care to enlighten?

There are 2 distinct but related forces acting upon an axle assembly due to applied torque reaction. One is where the diff/axle housing , via the diff pinion climbs around the crownwheel axis, sometimes referred to as 'axle roll'. The other force is where the axle housing tries to climb around the pinion axis. Propshaft torque tends to roll the vehicles sprung mass to the right hand side.if the upper link on a rear 3 link for example is offset to the right side of the axle, it should angle down from the axle attachment to the chassis attachment point so that axle roll will apply a lifting force to the right hand side of the chassis, thereby counteracting torque roll.If for packaging reasons, the upper link is offset to the left, then it should angle upwards from axle to chassis to have a similar effect by pulling the left hand side of the chassis down.

A 4 link can be similarly tuned by altering the axle or chassis attachment point of one upper link relative to its opposite number.

Cutting the front bushing section off hockey sticks to make the lower control arms for a 3 link is ok but the remaining attachment point behind the axle is far too high above the axle centreline to provide adequate resistance to torque reaction unless the top link is mounted a long way above the axle centre line to compensate. It is best to make up dropper brackets that bolt onto the hockey stick brackets to lower the position of the control arms to below axle centreline. Also, for 3 link, sleeve the bushing hole down to accept rear trailing arm bushings because the extra compliance of standard hockey stick bushings is not required and can lead to axle tramp or hop. In fact,the heavy contruction of hockey sticks is a bit of overkill for lower control arms, because they are only subject to tensile and compressive load from torque reaction, wheras radius arms are designed to withstand bending loads.

[muddy]

What´s the best way of doing that: A or B? (radius arms heated in forge and bent)

[img=http://img571.imageshack.us/img571/9087/frontaframe.jpg]

My idea is pic B with as said before one of si's joint at the chassis end, do we think the joint would be up to it?

Will.

[dirtydiesel]

I don't see the radious arm double bend gains anything, as the bushes will have to do some twisting anyway. And maybe if the anchor points are closer than say 12" you might as well go with a single ball?

Although single link has flex, it's hard to get away from the fact that standard, or 3 link, feeds the shock load of a wheel-impact direct to a chasis rail through a rubber bush and in a direct line. ( I do admire 4 link though, parralel or two triangles).

One of my concearns on flex was the way an 80" landy got around the place being front heavy. Lifting a back wheel was never a major issue as the front axel pulled you through

So then I was thinking that having the majority of the flex was better on the back. But I was still faced with the fact that the Bobcats got every where with no flex at all? And in the end I personally would rather wave a wheel than loose stability.If nothing else, I don't have to re-learn the trucks behaviour.

I think your percieved stabilty is an illusion, you would not belive how truely stable your car could be with totally balenced suspension travel front and rear.

I had radius arms front and rear on my G wagon, i had a about 11" of wheel movement per corner, i lifted wheels a lot but it didn't matter i had lockers, it felt fairly stable and predictable (as a 7 foot tall car can be!) Then i made 3 link setups front and rear and it totally transformed the way it drove, really really stable, climbed much better. the only thing i changed was the link arangement i kept the same springs and shocks.

I think a lot of the problems encountered by landrover owners suffer instability after changing link arrangement, is because in order to get the s**t radius arm setup to flex they run far too soft a spring rate, they continue these springs into the new link system and suffer accordingly.

As an example, the back of my nissan patrol is a very flexy 5 link setup, i run very high poundage springs OME +2" +250kg constant load, i can still flex to the limit of my shocks (about 30" wheel movemant) and i have total stability off road or at 60mph with a trailer on.

This is because the link arangement allows totally free axle movement, and the spriing rates are correct for the (huge) weight of the car.

But my outside-the-box front flex fix was going along the lines of a third radious arm in the middle of the axel. Simple enough on fabrication, and easily reversed if it didn't work well or just for a long road trip.The outers would have the end bolts removed and take end loads, the new inner would stop the axel twist. What I wasnt sure about was how much fore and aft movement this third radious arm would need at the anchor?

I'm not saying it was going to be awsome, but worth a think as a wierd 3 link

This setup has allready been tried and tested more than a few times, i think by someone on here has tried it as well, I looked around his truck at kirton once, he said it worked very well off road but had issues under braking on the road, i think he said the bush wear on the central arm was accelerated over normal as well.

[dirtydiesel]

DirtyDiesel, you typed this almost 7 years ago, I didnt understand it then, and I'm still struggling. Care to enlighten?

Wow, i knew that 7 years ago!

I'd done a pretty good job of putting it in words then, and my powers of description haven't improved enough to enlighten you further in words, over a cup of coffe and a axle i could show what i mean/meant.

[Daan]

I think your percieved stabilty is an illusion, you would not belive how truely stable your car could be with totally balenced suspension travel front and rear.

I had radius arms front and rear on my G wagon, i had a about 11" of wheel movement per corner, i lifted wheels a lot but it didn't matter i had lockers, it felt fairly stable and predictable (as a 7 foot tall car can be!) Then i made 3 link setups front and rear and it totally transformed the way it drove, really really stable, climbed much better. the only thing i changed was the link arangement i kept the same springs and shocks.

I think a lot of the problems encountered by landrover owners suffer instability after changing link arrangement, is because in order to get the s**t radius arm setup to flex they run far too soft a spring rate, they continue these springs into the new link system and suffer accordingly.

As an example, the back of my nissan patrol is a very flexy 5 link setup, i run very high poundage springs OME +2" +250kg constant load, i can still flex to the limit of my shocks (about 30" wheel movemant) and i have total stability off road or at 60mph with a trailer on.

This is because the link arangement allows totally free axle movement, and the spriing rates are correct for the (huge) weight of the car.

This setup has allready been tried and tested more than a few times, i think by someone on here has tried it as well, I looked around his truck at kirton once, he said it worked very well off road but had issues under braking on the road, i think he said the bush wear on the central arm was accelerated over normal as well.

I agree with the balanced suspension arrangement, that is what I have found as well on mine, where the springrates are in a 60/40 percentage, similar to the weight distribution. The comment about the radius arms, not to sure: I run these front and rear using the landrover early narrow bushes. I hardly ever wave a wheel in the air, I think it is a brilliant setup. People boast about the 'I have more travel than you' thing, but it is almost always at the rear where it happens, and you see the front axle doing nothing at all. It is more about the static deflection of the springs I reckon, which I aimed at being 50% percent of full travel. It is no ramp king, but works predictable in every situation.

My experience anyway.

Daan

[Daan]

much flex at the back, not much at the front:

http://www.google.co.uk/imgres?imgurl=http://www.fuddymuckers.co.uk/gallery/kittygrip/nige_slab_test.JPG&imgrefurl=http://www.pirate4x4.com/forum/land-rover/747190-d110-suspension-lift.html&usg=__xPHA61ZaB-IigsymtT58oeI3qVA=&h=536&w=800&sz=106&hl=en&start=1&zoom=1&tbnid=xuQeXtKoci95PM:&tbnh=180&tbnw=268&ei=MHMzUfSrNsK30QWvo4DYCg&prev=/search%3Fq%3Ddefender%2Bsuspension%2Bextreme%26hl%3Den%26sa%3DX%26biw%3D1600%26bih%3D684%26tbs%3Dsimg:CAQSUgnG5B5e0qhyLxo-CxCwjKcIGiwKKggBEgQjIkhGGiCX6LeAXJtGR3gk8_11d450IjF-fmlgnuJTlipm3-XmZSQwLEI6u_1ggaAAwhHej3xmEKqU0%26tbm%3Disch&itbs=1&ved=1t:3588,r:0,s:0,i:61&iact=rc&dur=1336&sig=101211353121289413835&page=1&tx=173&ty=104

another one:

http://www.google.co.uk/imgres?q=extreme+defender+suspension&hl=en&sa=X&rlz=1T4SKPT_enGB432GB432&biw=1600&bih=684&tbm=isch&tbnid=s40qnx_5ORm-8M:&imgrefurl=http://www.landyzone.co.uk/lz/f8/discovery-rust-boot-sills-wings-161843-75.html&docid=n00BkyPOqBgUCM&imgurl=http://i1141.photobucket.com/albums/n589/GreenHornet5/Green%252520Hornet%252520Build%2525202011/Suspension/8735ea19.jpg&w=1024&h=768&ei=o3MzUc-WH6iP0AXQ4oCgAQ&zoom=1&ved=1t:3588,r:58,s:0,i:263&iact=rc&dur=1639&sig=101211353121289413835&page=3&tbnh=181&tbnw=223&start=43&ndsp=26&tx=67&ty=79

High centered, high cofg:

http://www.google.co.uk/imgres?q=extreme+defender+suspension&start=389&hl=en&sa=X&rlz=1T4SKPT_enGB432GB432&biw=1600&bih=684&tbm=isch&tbnid=ekgtgB2LKpth2M:&imgrefurl=http://www.offroaddrivingschool.com/OEX_Fleet_4x4_driving_school_vehicle_choices.htm&docid=oqfpRiKu6dyBkM&imgurl=http://www.offroaddrivingschool.com/images/Buttons/Defender-90.jpg&w=900&h=675&ei=3nMzUdG0BIOc0QXN5YHYCw&zoom=1&ved=1t:3588,r:95,s:300,i:289&iact=rc&dur=6394&sig=101211353121289413835&page=16&tbnh=164&tbnw=259&ndsp=11&tx=193&ty=89

[RedLineMike]

much flex at the back, not much at the front:

http://www.google.co.uk/imgres?imgurl=http://www.fuddymuckers.co.uk/gallery/kittygrip/nige_slab_test.JPG&imgrefurl=http://www.pirate4x4.com/forum/land-rover/747190-d110-suspension-lift.html&usg=__xPHA61ZaB-IigsymtT58oeI3qVA=&h=536&w=800&sz=106&hl=en&start=1&zoom=1&tbnid=xuQeXtKoci95PM:&tbnh=180&tbnw=268&ei=MHMzUfSrNsK30QWvo4DYCg&prev=/search?q=defender+suspension+extreme&hl=en&sa=X&biw=1600&bih=684&tbs=simg:CAQSUgnG5B5e0qhyLxo-CxCwjKcIGiwKKggBEgQjIkhGGiCX6LeAXJtGR3gk8_11d450IjF-fmlgnuJTlipm3-XmZSQwLEI6u_1ggaAAwhHej3xmEKqU0&tbm=isch&itbs=1&ved=1t:3588,r:0,s:0,i:61&iact=rc&dur=1336&sig=101211353121289413835&page=1&tx=173&ty=104

/quote]

the first picture is our very own Hybrid from Hell

[Daan]

I know...

[bill van snorkle]

I've rolled quite a few 4x4's over in my time, and very few of those upsets occurred when the trucks were perpendicular to the gradient.They mostly occurred on standardish trucks when cross axle articulation limits were exceeded. I'd imagine that with a few beefy helpers and a tether strap, it would be relatively easy to quantify relative stability of a flexibile suspension system verses a more rigid setup by experimenting with just the one truck. I am picturing finding a V gulley with suitably steep banks.On the first attempt, drive the truck across the gulley at an oblique enough angle to get the suspension all flexed up. For second attempt, block or chain the suspension at all 4 corners to prevent or limit any articulation and try the gully at the same oblique angle, and have your helpers ready on the tether to prevent a possible rollover.

It goes without saying that the truck should be fitted with at least one difflock.

[o_teunico]

Propshaft torque tends to roll the vehicles sprung mass to the right hand side

Is this an example of that?

[bill van snorkle]

"Is this an example of that"?

Yes. But since the advent of air suspension on heavy vehicles, I've seen many poorly designed link arrangements with very short panhard rods and half parabolic leaf springs employed as radius arms that produce excessive rear antisquat, that it is difficult to know what is going on with that truck, when the one beside it isn't tilting to the right.

[o_teunico]

The more 1Link setups I see, the more I like them...It´s so simple and flexible...In a coiler the axle will need no modification and the bolt-on gbox crossmember and radious arms will be very easy to adapt to this system.

It will be also extremly easy to revert it to hockey stick+panhard setup

[bill van snorkle]

As I mentioned earlier, do try to make the one link at least as long as the hockey sticks to avoid excessive castor angle variation as the suspension cycles. The standard location of the bolt on crossmember is a little too far forward to allow that, so should be moved rearwards or cranked.

[o_teunico]

Sourced from Difflock forum...

Si´s mighty x-joint

More here http://forum.difflock.com/viewtopic.php?t=16760&postdays=0&postorder=asc&start=0

[simonr]

Can I just add - that my joint is not suitable in standard form.

The problem is that as a trailing arm joint, the forces are only longitudinal whereas in an A frame, there are fairly high sideways forces on it as well. This leads the stem of the ball to fatigue & fail!

For mine, nicks and a couple of others, the solution was to make a slightly different version of the ball

EN24 Ball.SLDPRT

Made from EN24 steel instead of EN8 and with a tapered shaft. Screwed tight into the threaded boss it works fine.

On mine, I machined a new boss with a lip around the edge. You then hammer the lip flat against one of the flats on the ball to ensure it doesn't unscrew.

Si