Solid leaf-springs

[jorgeopesi]

Leaf springs are made from spring steel which is made to bend and return to it's shape, the plastic plates are molded and not made to bend at all.

Hulk sure can, just kidding dude .

[Someonenamedjon]

what if they accidentally made it with a thin piece of metal that only carriers 100 pounds without car body weight!

[Blakbird]

Leaf springs are made from spring steel which is made to bend and return to it's shape, the plastic plates are molded and not made to bend at all.

Every solid material bends under stress. Most materials follow an elasto-plastic behavior. Under a certain range of loads, the parts will bend proportionally to the load and then return to their original shape. This is elastic deformation. If loaded beyond a certain point called the "proportional limit", then the parts will permanently deform and not return to their original shape. This is plastic deformation. Unfortunately, the word "plastic" used as an adjective to describe permanent deformation has nothing to do with the word "plastic" used as a noun to name polymeric materials. "Plastic" parts actually "elastically" deform for a while. As long as you stay under the proportional limit, this does no harm. So making torsion bars and leaf springs is just fine. If you exceed the proportional limit then the material will start to turn white and will strain very far and be permanently damaged.

[Bzroom]

I'm using Hose Soft Axle for my leaf springs. Why? because they look good, work well, and are to scale. The suspension on the moc is pretty much useless at that scale, but it looks good.

[Someonenamedjon]

hehehe cheepo

[Paul Boratko]

Every solid material bends under stress. Most materials follow an elasto-plastic behavior. Under a certain range of loads, the parts will bend proportionally to the load and then return to their original shape. This is elastic deformation. If loaded beyond a certain point called the "proportional limit", then the parts will permanently deform and not return to their original shape. This is plastic deformation. Unfortunately, the word "plastic" used as an adjective to describe permanent deformation has nothing to do with the word "plastic" used as a noun to name polymeric materials. "Plastic" parts actually "elastically" deform for a while. As long as you stay under the proportional limit, this does no harm. So making torsion bars and leaf springs is just fine. If you exceed the proportional limit then the material will start to turn white and will strain very far and be permanently damaged.

I would be more concerned damaging the actual connector or axlehole base to where the "torsion bar/axle" is being mounted to, rather than the axle itself.. This would more than likely be where damage would occur before any type of deformation to the axle would happen...

[Bzroom]

They're actually $1.00 for new red ones. Not very cheap. It's the most questionable part of making my moc plans available.

[Paul Boratko]

They're actually $1.00 for new red ones. Not very cheap. It's the most questionable part of making my moc plans available.

For what size..?

[Bzroom]

12m from LEGO customer service. On brick link, for "new" they seem to be about the same price. Of course i could roll the dice on used ones. I probably will. But I want some fresh ones for the photos.

4501304 new from LEGO actually cost $1.25

Edited April 5, 2013 by Bzroom

[Paul Boratko]

12m from lego customer service. On brick link, for "new" they seem to be about the same price. Of course i could roll the dice on used ones. I probably will. But I want some fresh ones for the photos.

What's funny is that I was told the 19 ones are actually cheaper than the 12 and 11 ones from Lego...

[jorgeopesi]

Looks like we can make the leaf-spring chat .

[Paul Boratko]

Brick Takeover from Germany has them for .42 cents each and his shipping is very reasonable.. I have bought from them many times... Great to deal with...

[Someonenamedjon]

it probably going to spring to some random things too....

[Bzroom]

Red $ 1.25

Black $ 0.85

:/ but i want them to pop!

Thanks Paul, i'll give them a shot.

Good find. I must not know how to search correctly. When i found the item on bricklink, and then instructed it to sort by NEW, there was only one result, and it was the expensive one.

Edited April 5, 2013 by Bzroom

[nicjasno]

All valid points, but the solid leaf springs that i use are real leaf springs, they do not damage eithet the plates used for the springs, nor the mounts. In the dropbox link is a subfolder with a smaller version of the leaf springs. Also, the longer the leafs, the softer the suspension.

The deformation also happens over a long length of plate, and does not harm the plates. I had leaf springs mounted in the dodge charger model for 2 years (and the model weighed 6kgs. The plates that served as leafs are still straight and undamaged, and that suspension had about 3 studs of travel.

Also, another part of the leaf spring suspension is the fact, that no other links are needed to guide the axle, just the 2 leafs.

Edited April 5, 2013 by nicjasno

[Someonenamedjon]

Good find. I must not know how to search correctly. When i found the item on bricklink, and then instructed it to sort by NEW, there was only one result, and it was the expensive one.

on bricklink you always have to sort by how cheap it is, not by new or used, but with sets i recommend new sets

[Boxerlego]

After my other rare leaf-spring suspensions to develop... (http://www.eurobrick...=74420&hl=kamaz). Now a new ones with more structural capacity, easily adjustable, smaller and work well until now... Now I just need to know what truck build up? . The steering would be like the Sheepo´s Land Rover system.

Ideally a leaf springs needs to be strong and solid with the axle. Your previous Leaf spring design was more solid and strong. This setup looks soft and flimsy for the axle and looks functional have you tested it. Does it work?

Why not use proper leaf springs?

Like i use here: https://www.dropbox....u4sy/C6u888pHF5

On a proper leaf spring, the leaf spring bends in a concave inward direction. The example in your video reflects the opposite. It Is more suited for a mechanical damper spring where the spring is always under tension. The true practice of leaf spring uses the compressional facts of the arch. Your just bending Lego and saying it is a leaf spring. I think the Idea is great, and definitely the start of something good, but it is lacking the true proper form that brings function for a proper leaf spring.

and thats why you shouldn't even attempt leaf springs in lego

Right now a group of people in japan are trying to create a LEGO robot that will be able build with LEGO and we cant even attempt a proper leaf spring setup.

[Lipko]

Every solid material bends under stress. Most materials follow an elasto-plastic behavior. Under a certain range of loads, the parts will bend proportionally to the load and then return to their original shape. This is elastic deformation. If loaded beyond a certain point called the "proportional limit", then the parts will permanently deform and not return to their original shape. This is plastic deformation. Unfortunately, the word "plastic" used as an adjective to describe permanent deformation has nothing to do with the word "plastic" used as a noun to name polymeric materials. "Plastic" parts actually "elastically" deform for a while. As long as you stay under the proportional limit, this does no harm. So making torsion bars and leaf springs is just fine. If you exceed the proportional limit then the material will start to turn white and will strain very far and be permanently damaged.

What about creep? It's there even if you are under the proportional limit.

Edited April 7, 2013 by Lipko

[nicjasno]

Sure, but we cannot have eliptical things in lego. I still think my approact is the closest to real life leaf springs that we can get in lego at the moment.

Edited April 8, 2013 by nicjasno

[Someonenamedjon]

I bet you could probably do that if you had custom made parts..

[dhc6twinotter]

A while back, somebody posted a "leaf" spring suspension using the old steering rack and the steering rack bracket

I can't remember who did that, but it seemed to be a good solution for building leaf spring suspensions.

Edited April 9, 2013 by dhc6twinotter

[DLuders]

@ dhc6twinotter: It was LUGPol member vonsmallhausenPL who designed that leaf spring suspension with those parts -- see this Eurobricks topic for details.

[jorgeopesi]

Nice idea! .

[dhc6twinotter]

Thanks for the links, David!

[Blakbird]

What about creep? It's there even if you are under the proportional limit.

Creep is important in certain metals, especially at extremely high temperatures, but it is not a factor in LEGO parts. If a LEGO torsion spring does not permanently deform immediately under load, it is unlikely to do so even after years of support.