[WIP] 2019 Formula 1 car (help wanted)

[TheHypaaa]

Hello,

I haven't really posted anything before so I'm not excatly new but regardless:

Over the last few months I've gotten really in Formula 1 so I decided to try to recreate the unique suspension that is used nowadays. The primary difficulty being that modern lower wishbones are mounted on the same height as the wheel mounting and the upper wishbone closely above that. I think I have succeded in doing so (in the front and the rear) but I have a new problem now: Considering that the chassis part where the wishbones attach to can't be very wide or high, I can't think of a way to increase the stiffness of the suspension setup. Right now the suspension is too soft, it can only handle about 150g of force before beginning to compress which wouldn't be enough when the whole 1:8 car is completed. 

So if anyone has an idea or suggestion of how to increase the stiffness I would be very grateful! 

 

I also have an .lxf file of the build (red colored is the most up to date one): https://1drv.ms/u/s!AmTylFNEfzF2hNAS890w5GgEc4NJRg?e=8LBLW6

 

 

Edited September 1, 2019 by TheHypaaa

[Seasider]

Hi, I’m guessing from the image you’ve got yellow springs hiding in there from your image. Have you tried the red springs, I think they’re stiffer.

[TheHypaaa]

Thanks, yes those are the yellow springs. I sadly don't have the red ones but I think the difference would not be enough to make a significant difference :(

[weavil]

The 42000 could be worth a look at. I have it and to me it  felt stiff. There are F1/Indy car MOC's out there that you could look at too.

[Berthil]

F1 cars don't have a suspension travel that is very big, it's not an off-road car. You can put a 4265c bushing in with the spring to stiffen it up. Or even two springs or two bushings depending on suspension geometry. RoscoPC does it all the time in his historic F1 models.

[Jeroen Ottens]

This is all about geometry. If you want to have a stiffer suspension with the same travel on the wheels you'll have to make sure that the springs are compressed more with the same limited travel. One way to do that is by making the lever that connects to the springs longer, or make the lever that connects to 9L link with balljoints shorter. Your current setup has a 2L length (it's a 3L beam with crossholes, but center to center that is 2L long) lever towards the spring and a 2L length towards the links. That gives you a 1:1 ratio between movement of the 9L link and the spring. The spring can move 1.5 studs, so the link also can move 1.5 studs. If you would make the lever to the link only 1 stud long a 0.75 stud movement of the 9L link gives you a 1.5 stud travel of the spring. So you'd get a 2x stiffer suspension. Obviously you can also increase the length of the lever to the spring to get the same effect, but that will require a wider body. To get the same 2x stiffness your 3L beam will have to grow to a 5L beam, making the body 10L wide (or figure out a way to have these links crossing each other)

In your setup the 9L link is almost horizontal. As a result the vertical movement of the wheel is translated only into a small horizontal movement of the link. So another way of improving the setup is by angling the link more upwards, than you also get a better ratio between the vertical movement of the wheel and the horizontal movement of the link. But I guess that was the kind of look you wanted to try to avoid.

You can also make a more elaborate linkage system in the body of the car that amplifies the movement of the lever that would normally go the spring, but I wouldn't advice that, since it will introduce a lot of play in the system.

I hope I explained it well

[TeamThrifty]

f1 suspension uses heave springs in addition to what you already have - that will increase stiffness

Edited September 2, 2019 by TeamThrifty
typo

[TheHypaaa]

1 hour ago, Jeroen Ottens said:

This is all about geometry. If you want to have a stiffer suspension with the same travel on the wheels you'll have to make sure that the springs are compressed more with the same limited travel. One way to do that is by making the lever that connects to the springs longer, or make the lever that connects to 9L link with balljoints shorter. Your current setup has a 2L length (it's a 3L beam with crossholes, but center to center that is 2L long) lever towards the spring and a 2L length towards the links. That gives you a 1:1 ratio between movement of the 9L link and the spring. The spring can move 1.5 studs, so the link also can move 1.5 studs. If you would make the lever to the link only 1 stud long a 0.75 stud movement of the 9L link gives you a 1.5 stud travel of the spring. So you'd get a 2x stiffer suspension. Obviously you can also increase the length of the lever to the spring to get the same effect, but that will require a wider body. To get the same 2x stiffness your 3L beam will have to grow to a 5L beam, making the body 10L wide (or figure out a way to have these links crossing each other)

In your setup the 9L link is almost horizontal. As a result the vertical movement of the wheel is translated only into a small horizontal movement of the link. So another way of improving the setup is by angling the link more upwards, than you also get a better ratio between the vertical movement of the wheel and the horizontal movement of the link. But I guess that was the kind of look you wanted to try to avoid.

You can also make a more elaborate linkage system in the body of the car that amplifies the movement of the lever that would normally go the spring, but I wouldn't advice that, since it will introduce a lot of play in the system.

I hope I explained it well

Thanks a lot! I think I think I habe an idea of what I could do.

[steph77]

Did you try to add a 1/2 bush Inside your shock absorber?

Do like below with yellow ones. Must solve your issue Simply.

 

[sicadus]

2 hours ago, Jeroen Ottens said:

This is all about geometry. If you want to have a stiffer suspension with the same travel on the wheels you'll have to make sure that the springs are compressed more with the same limited travel. One way to do that is by making the lever that connects to the springs longer, or make the lever that connects to 9L link with balljoints shorter. Your current setup has a 2L length (it's a 3L beam with crossholes, but center to center that is 2L long) lever towards the spring and a 2L length towards the links. That gives you a 1:1 ratio between movement of the 9L link and the spring. The spring can move 1.5 studs, so the link also can move 1.5 studs. If you would make the lever to the link only 1 stud long a 0.75 stud movement of the 9L link gives you a 1.5 stud travel of the spring. So you'd get a 2x stiffer suspension. Obviously you can also increase the length of the lever to the spring to get the same effect, but that will require a wider body. To get the same 2x stiffness your 3L beam will have to grow to a 5L beam, making the body 10L wide (or figure out a way to have these links crossing each other)

In your setup the 9L link is almost horizontal. As a result the vertical movement of the wheel is translated only into a small horizontal movement of the link. So another way of improving the setup is by angling the link more upwards, than you also get a better ratio between the vertical movement of the wheel and the horizontal movement of the link. But I guess that was the kind of look you wanted to try to avoid.

You can also make a more elaborate linkage system in the body of the car that amplifies the movement of the lever that would normally go the spring, but I wouldn't advice that, since it will introduce a lot of play in the system.

I hope I explained it well

Agreed it all about understanding basics of geometry, after that things get a whole lot easier...

[TheHypaaa]

4 hours ago, steph77 said:

Did you try to add a 1/2 bush Inside your shock absorber?

Do like below with yellow ones. Must solve your issue Simply.

 

I looked that up already earlier and found a post on here from some time ago and I think Jim said that it doesn't actually increase stiffness due to the fact that the coefficient of the spring doesn't change or something similar.

[Jeroen Ottens]

43 minutes ago, TheHypaaa said:

I looked that up already earlier and found a post on here from some time ago and I think Jim said that it doesn't actually increase stiffness due to the fact that the coefficient of the spring doesn't change or something similar.

It doesn't change the stiffness indeed, but it does increase the pre-tension of the spring. That way it will take more force before the spring starts to compress.

[TheHypaaa]

1 hour ago, Jeroen Ottens said:

It doesn't change the stiffness indeed, but it does increase the pre-tension of the spring. That way it will take more force before the spring starts to compress.

Ah very good to know, thanks! Very helpful for my intention.

[Gray Gear]

Please, but especially if you plan on upgrading the Springs, dont use that yellow connector on such a heavy duty task. Its a quite fragile Brick, so it will definatelly break sooner or later. Suspension design needs to be sturdy a f. And I dont think that yellow connector can reliably handle 0.5kg or more of force, which it would have to on a 1:8 model. Such big Models get heavy really quickly.

[letsbuild]

On 9/2/2019 at 2:32 PM, Gray Gear said:

Please, but especially if you plan on upgrading the Springs, dont use that yellow connector on such a heavy duty task. Its a quite fragile Brick, so it will definatelly break sooner or later. Suspension design needs to be sturdy a f. And I dont think that yellow connector can reliably handle 0.5kg or more of force, which it would have to on a 1:8 model. Such big Models get heavy really quickly.

I was about to say the same. Lego once did this with one of their F1 cars too, and the results were many broken connectors. I think they were even yellow too.

[Vectormatic]

Just now, letsbuild said:

I was about to say the same. Lego once did this with one of their F1 cars too, and the results were many broken connectors. I think they were even yellow too.

yup, 42000 has pushrod suspension with that connector, mine is fine, but it just sits on a shelf

[Gray Gear]

The only parts you want to trust with the force of the hard springs are Liftarms/Technic Bricks and axles, and maybe, maybe some pins.

[Appie]

Indeed gray gear, currently building a F1 car in this scale as well. I pretty much avoided that part and this one

in the suspension setup since they can break easily.

Edited September 12, 2019 by Appie