Anyone tried the wishbone part as a torsion bar pseudo leaf-spring in suspension?

http://alpha.brickli...page?P=x136#T=C

Would be for trucks around the Arocs-size (would be heavy, with PF and batteries - picture at end of post).

Used multiple times as a pseudo-spring in super-heroes sets, desert racers and so on, but they're much smaller vehicles.

I don't want to use coil springs, and there's no original Lego part equivalent to actual leaf springs (think Efferman maybe has some from shapeways).

Concerned about getting a strong connection at the pinholes, and that because the bar is bent, it will try to twist and rotate out from the pin holes as it deflects under load. Also there's only a single pinhole at one end, makes a rigid connection tricky eh?

I could just test it, but eh, there might be shortcuts

The steering axles on this are currently unsuspended and it bounces too much on bumps. Rear axles are walking beam, but the front is too widely spaced for that. Suspension can't be mushy, there's no front outrigger, crane will fall over...

Yair, I did photograph a black + red truck on a red rug. Yuck 4x L-motors for drive though, it scoots well.

Edited December 3, 20159 yr by andythenorth

Do you mean to use it as a sort of leaf spring? Torsion bar suspension is something different entirely, mostly seen in tanks and tracked armored vehicles.

Do you mean to use it as a sort of leaf spring? Torsion bar suspension is something different entirely, mostly seen in tanks and tracked armored vehicles.

Yes, I mean exactly that thanks. I've edited the original post. I forgot what a torsion bar is

Edited December 3, 20159 yr by andythenorth

I toyed with the idea and it works reasonable well.

It has a tendency to twist when only one wheel is connected to one wishbone. By adding a solidaxle between the two wishbones you can get independent suspension without the wheels tilting sideways, but the structure becomes bulky quickly.

In one of the Chima sets it was used by TLG...

I once used them this way

If you want to replicate leaf-springs, try flexible axles.

as leafprings I only use axles and they work perectly....simulates real leafspring with no problems...holding up to a kg ow weight...if not more...bend in a proigressive way and still remain quite soft when the truck is not loaded...

I use 1x12 plates for leaf springs. On a large heavy truck build I used 2 of 1x10 (to make a 1x20), 1x12 then 1x8 stacked on top of each other, separated by smooth tiles so they could slide. this set up allowed the truck to handle a load of 18kg before the suspension was fully compressed.

Edited December 4, 20159 yr by allanp

as leafprings I only use axles and they work perectly....simulates real leafspring with no problems...

Could you post a pic of these as i'm very curious as to how you've accomplished this.. and sound like a very interesting building technic

I personally like the leafsprings Efferman made on shapeways.

Don't kbow yet how to incorporate them in the models, but I will see what I will do in the future.

Could you post a pic of these as i'm very curious as to how you've accomplished this.. and sound like a very interesting building technic

soon will be posted...I just need one more brickowl order to complete the rest of the truck!

I personally like the leafsprings Efferman made on shapeways.

yes efferman did a nice job but I still don't see the point of that 3D parts as leafsprings are esily achievable with normal lego parts

They just look very realistic, like that.

And yes it can be easily achieved with Lego parts.

But for realism, they some times just don't cut it.

Ah, found some pics:

Not quite the look I am going for.

Ah, found some pics:

I actually like them but tbh I would have never thought that they could carry that amount of weight.. Nice work AllanP

Edited December 4, 20159 yr by Siegfried Meyer

To test the weight I placed it on a bathroom scale, zeroed the scales and then placed my foot down on it and kept pressing until the little yellow springs were fully compressed. It took around 18-20 kgs to fully compress the springs. Not sure how accurate that method was but I'de say it was about right. the suspension was very strong but can also be scaled down nicely.

Ah, found some pics:

That seems like a pretty good solution! Definitely the most true-to-life setup I've seen . Any permanent deforming of the parts?

No deformation that I could tell after disassembly but then the model was never fully complete and it wasn't built very long before I got board and moved on the the next idea. I only took pictures of this part for future reference as it worked really well.

Edited December 4, 20159 yr by allanp

Yair, the plate leaf springs are impressive. Won't fit the truck I'm building though

Axles might work. Or I need to figure out a walking beam with a wide axle spacing...

Edited December 4, 20159 yr by andythenorth

Going with a simple walking beam + thrust rods. It's preferable that it's unsprung because it's a crane carrier that has no front outrigger (springs would compress when lifting over the front).

Here's an ugly mockup, functions well.

Edited December 5, 20159 yr by andythenorth

Nice setup but as you said it's not unsprung! Why don't you use instead of the beam a normal axle and then add 4 pneumatic cylinders? so this will give you more leafsprings effect but still suspended via pneumatics…which actually real cranes have anyway and they look cool!

I could add springs where the 3x5 L-beams are (one of them is red in the pictures).

Some vocational trucks (cranes, mixers) etc have twin-steer walking beams set up that way.

Probably won't though, overkill