Tandem Torsion Axles Suspension Action

[@rogerhodges9721]

Clever design and a huge improvement over standard trailer suspension. I am impressed!

[@beachboardfan9544]

Why is this a huge improvement over leaf spring axles?

[@pauldavidson6321]

I need this ,clipping kerbs is mainly how I tow trailers.

[@Obi1kenobi10]

Doesn't everyone clip kerbs?

[@AtariFTW]

A great solution for the issue of one torsion axle bearing more weight than the other due to the trailer not being level.

[@geepeerces]

be real interesting to see this with the load sharing beams intentionally locked in place so it behaves like a conventional dual torsion setup, doing the same maneuvers at the same slo-mo, side by side so we could really compare the differences.

[@SyEnsability]

That's a good idea.

[@victorgamer9534]

Exelente proyecto no hace falta amortiguadores.

[@Obi1kenobi10]

Would like to see this under a load.. I'm building a new trailer for work and I like this idea.

[@tonywarmsbecker8952]

see this work with 2 8k axles, don't think center pivot could be built strong enough, to hold that weight, turning would twist the crude out of that setup.

[@anomilumiimulimona2924]

Torsion axles are like three times the cost of regular beam axles

[@ir1798]

I'm intrigued by your walking beam suspension system for tandem axle trailers with torsion axles. My question is: is angular torsion a concern? For example: if one wheel goes over a tall obstacle the walking beam will pivot and potentially induce a rotational deflection on the axle?

[@SyEnsability]

True, it does introduce a torsional element. No, it's not really a concern. The axles are mounted in rubber which allows some motion between the axles and the rocking beams. The beams do have torsion, like going up the step, and that's part of why the wheel lifts in the video. The torsion is constrained by the rocking stops.

[@eldridge201]

At 1:16 when it’s going over that small curb, there is only one tire touching a surface (the front tire) such as the curb or sidewalk or pavement and this would indicate that all the weight would shift on that side and only be on one tire and/or axle on that side anyway. At least at that particular moment. I’m not an engineer but I would assume that all the weight on one tire or axle on one side instead of distributing the weight a little better between both tires and axles on that side would not be a good thing since you would be putting all the stress and weight on only one tire and axle. If your axles are rated at 5000 each and you have roughly 10,000 total weight on the combination of axles including trailer weight and the cargo on the trailer and you’re going over a bump or curb like this and 1/2 of that is supposed to be on that side of the trailer, if 1/2 of one of the 5000 pound axles is 2500 pounds but it is suddenly getting roughly 5000 pounds of weight, isn’t this double what a single axle “should” be handling? Furthermore, isn’t this double what a tire “should” be handling? If you had a heavy load and you did this, I would think that this could potentially damage a tire or axle or possibly more if you weren’t careful. I would worry that this could twist the axles a little too much possibly as well as it looks like there isn’t much “give” in the setup.. Again, I’m not an engineer so perhaps I’m way off here but I would be concerned since this was only a small amount of travel to get on that curb.

[@SyEnsability]

Good observations, and you're not far off. This trailer is quite light, so when empty the rubber grommets that set spacing and allow articulation are not deflecting. That gives it an artificial appearance of stiffness, and yes, the rear wheel lifts. Under some load, not even that much, the wheels track the ground. Full story at www.synthx.com/torsion-axle-walking-beam-suspension/

[@ygtcbee23]

Have you shown this to PJ or Big Tex Trailer? This is good development

[@HubertofLiege]

ygtcbee23 old technology

[@garthrichert5256]

What happend to the opposite set of wheels if they are going over an opposite angle obstacle at the same time / wont it twist the whole frame ?

[@SyEnsability]

There are some rubber thrust and twist bushings as part of the axle mounting that give the system some flex. Good question. Enjoy.

[@jamesrobinson5801]

How about the Torsion Stress this applies to the Beam section of the Torsion Axle. The Square Tube in the Beam is not designed to twist. Say you cross the load equalizer through a ditch like section, front right in full compression and left rear in full compression, that twist FAR exceeds the design of a Static Axle Tube. Torsion Axles are designed so the Flange mounted to a static load takes the full load and twist while the connecting Beam from one side to the other is only there to keep the Camber and Caster of the wheels in line.

[@SyEnsability]

Good eye. You are absolutely correct if the axles were rigidly mounted to the rocking beams. They are not. While the tube does take some torque, it is mitigated by flexibility in the attachment. That said, there are limits. If it was set up with too much rocking freedom, it would be just as you describe. Thanks for the comment.

[@jaba512]

Would this suspension type benefit of having shockabsorbers on the axles?

[@SyEnsability]

Interesting question. One of the nice things about torsion axles (rubber suspension) the rubber has a natural hysteresis that acts as a damper -- not quite as effective as a shock absorber, but pretty good. There might be some benefit, but I don't think it's needed.

[@jaba512]

@@SyEnsability I was thinkin about dampening the "tilt" - meaning the "seasaw" movement.

[@SyEnsability]

@@jaba512 Since both ends are damped with the rubber, then motion of the rocker beam is also effectively damped. It can't really rock without compression and extension of the axle arms, so I don't think additional damping of the rocker beam will help. In fact, it might hinder the instant reaction it gives to holes and bumps in the road. The reason for shock absorbers is to damp oscillation - like bouncing. The rubber does that fairly effectively. I own this trailer and it is pretty smooth pulling compared to many other trailers I've had.

[@SS-kz7ug]

👍

[@genesisdiaz5456]

Y para 3 ejes ??

[@marcossanchez1245]

Me parece q falta sistema de amortiguación porque cuando monta el cordón de la vereda la rueda trasera se levanta en el aire. Necesitaría una fuerza que empuje el neumático contra es suelo compensando el desnivel en forma negativa.

[@dollywarrior]

What exactly is going to absorb the shock ?

[@cataliculetz]

i could be wrong, but the whole weight of the load sits on 2 screws and 2 nuts, where the fixed chassis is connected to the rocker beams. isnt this dangerous?

[@SyEnsability]

Not sure what you are seeing. If you're talking about the 2 big pivot bolts, one on each side, yes they are overkill, and double secured.

[@cataliculetz]

@@SyEnsability ok, It's hard to tell from the video if it's an overkill.There is constant friction and and force applied to those bushings, both vertical due the load of the trailer and also horizontal force when pulling the trailer in a circle. That connection should be at least a good quality bearing able to take the whole load of the trailer and even that is not enough to take the horizontal force.

[@cataliculetz]

drive.google.com/file/d/1clYojrIeTZV4J3IcWhz42a2CcIvPPUsT/view?usp=sharing

[@rastaman7260]

@@SyEnsability Thanks for having patience. Engineers and customers should never meet. lol This is awesome building this now.

[@curtissiwak5349]

It looks smooth, can that trailer and suspension combo support 5000 pounds ?

[@SyEnsability]

This one does up to 4000#. The other one will carry up to 8000#. See mechanicalelements.com/diy/walking-beam-suspension-plans-8k/

[@nirodper]

I don't get what are you using as a bushing or bearing in the pivot point, is it metal on metal?

[@SyEnsability]

This one is a Greased pivot, typical of Trailer suspension. Larger diameter than most for increased surface area. Keep in mind a design parameter was "low cost". Implement bearings by machining the bores and shafts + seals. Adds significant complexity and cost. It all depends on how it's going to be used.

[@nirodper]

@@SyEnsability true, it would be great if there was an off the shelf rubber bushing or silentblock like the ones hendrickson suspensions use that's affordable and heavy duty that could be repurposed for this

[@davidraybould6987]

Cool design but all the weight is on the center bolt of the walking beam not a good design for a car hauler

[@patrickhayes3099]

Any alt options for higher ground clearance?

[@SyEnsability]

2 options. Larger wheels. Nominal torsion arm angle down.

[@dennismoody8140]

Would like to see this trailer in real action like under a heavy load, and will that system work under a car trailer with a car or pick-up on it

[@SyEnsability]

The system could be designed that heavy, but right now we have 2 options: 4000# and 8000# max. mechanicalelements.com/diy-plans/trailers/trailer-accessories/ I will try to record something next time the trailer is heavy loaded.

[@patrickhayes3099]

@@SyEnsability Can one build this with half axles? Flexiride torsion axles are available in short lengths that would allow for better clearance, IMO.

[@SyEnsability]

@@patrickhayes3099 No, this design is for full axles. Not designed for the moment of a wheel off to the side. For a single axle use the timbren axle-less product. Do not use it in tandem, however.

[@patrickhayes3099]

@@SyEnsability thanks. I thought as much. Still like the design. Shipping on full axles is killing my budget!

[@douglasbiel]

Eu acho que nao precisa desse eixos se remover esse eixo ficaria melhor, por que se apenas um lado passar por um buraco ou um desnível, o eixo inteiro vai se mover e acaba que os dois lado irao se mover se remover os eixo eu acho q ficaria melhor..

[@inspetorgambiarra]

Muito bom.

[@jwhunt3]

Have you come up with or seen a way to implement something like this with a triple axle trailer?

[@SyEnsability]

That's a great question. I've seen some stuff with heavy equipment, but nothing smaller / less complex.

[@adamkubiak6966]

I nie potrzeba żadnych sprężyn, amortyzatorów czy silent-block ów? Tak samo z siebie to amortyzuje nierówności?

[@SyEnsability]

Rubber within each torsion axle tube is the spring for each individual wheel. Then, the rocker beam transfers a balance with all the others. There is also a rubber bumper for bottom-out -- front and back.

[@yolo_burrito]

I don’t think those axles are designed to take off camber torsion like they will.

[@vidkardavilavictorino7571]

Pero que es paraque sirve

[@mp-xt2rg]

That isn't torsion suspension you just mounted two axles on a beam for articulation around a central point. The only "suspension" you have is the tires. You basically made a trailer with no suspension that can equalize load between tires.

[@SyEnsability]

Look a little closer. They are twin torsion axles that absolutely isolate and suspend on the rubber interface. Enjoy.

[@mp-xt2rg]

@@SyEnsability I guess I'm not seeing it. What what mechanism is allowing both wheels to move up or down at the same time?

[@kevinhornbuckle]

Put air bags over the axles.

[@niveknospmoht8743]

Obviously I see this as a fail since nothing has come about it in 3-1/2 years. I do not see the advantage over the torsion axles alone with an additional 100 lbs? and a pivot point of wear. 1 pivot bolt on each side is the only thing holding this whole thing together. A fully loaded 10k trailer with 1 pivot on each side controls the whole thing? Too much to go wrong

[@andrewlippincott]

Problem is when you have torsion axles bolted directly to the frame it is way easier to over load a torsion axles which can be dangerous..... This system eliminates that issue.

[@vidkardavilavictorino7571]

No yeva cargado nada no sirve

[@steverx4460]

It looks heavy. And expensive.

[@SyEnsability]

Heavier than springs, definitely, yet the mechanism weighs less than an axle. More expensive? Yes, some. It's not about light or cheap, it's about changing performance. Thanks for watching.

[@peterphoenix6471]

all that stress on that one bolt.....

[@SyEnsability]

Interesting observation. It's a big bolt, to easily take 10 times that much. Enjoy!

[@peterphoenix6471]

@@SyEnsability yeah i don't know the technical specifications for its stress performance, but i just imagine driving around carrying 2 tonnes then hitting an obstacle i.e. a kerb or rock at sufficient speed....that'll be the test.

[@davidcook5295]

It’s a poor design…you want to load each torsion independently for the benefit of a dual axle torsion setup. This might be better if you in the habit of jump curbs…maybe Load it, and this design is not as good as a standard setup, cost more, and much more prone to failure and suspension wear.

[@SyEnsability]

Yes, it costs a little more - and gives a nicer ride. This one has a lot of miles, with all sorts of loads. For those that drink the typical independent tandem torsion Kool-Aid, I suggest a good look at the physics. Torsions are wonderful as a single axle, but without extra mechanics, create problems when combined. Perhaps this article will help: mechanicalelements.com/torsion-axles-in-tandem-or-triple/

[@hikerJohn]

No one can say this is good intill you test it under a working load. Who cares how it handles with no load. Put 7,000 pounds on it.

[@abodakl10]

👎No