development time for carbon wheels

[Diablo_niterider]

and by the way besides tu graz

tu stuttgart
elephant racing

ran on cf wheels during endurance.

does anyone know what times tugraz was clocking during endurance .

[blister]

Weight savings are not only achieved with carbon fiber only.

There are other concepts, like running smaller engines or/and tires.

Look also at the cars from stralsund or helsinki. Both very fast cars with big engines and big wheels but not too much carbon fiber used.

I would start with simpler parts. Maybe the Steering Wheel?

[PSUAlum06]

Carbon fiber bodywork and a steering wheel are probably a good place to start, and A-arms would be a good second step. Wheels and uprights might be more trouble then they're worth. Just be warned, carbon fiber isn't a cure-all material.

The other thing to keep in mind is that low weight is secondary to just having a well setup car with good handling. I know of one 250 kg car for example that will beat about 85% of the field at any comp.

[flavorPacket]

There is no need to do carbon anything in FSAE. Look at wisconsin and stuttgart.

Michigan weighed in at 397 (180 kg) with a turbo F4i, 2 huge radiators, and dry sump with no carbon components aside from the steering wheel, seat, and bodywork. You can do the same.

And to my knowledge nobody has done a carbon upright, though I'm sure many F1 teams are trying.

[blister]

I must say, that just looking at numbers like weight, stiffness or inertias, carbon fiber rims can definitely improve the lap time. We are developing cfrp rims with 5 spokes. The guys spent nearly 9 months till now. At the moment we have negative forms. Maybe we can show a presentation model at FS Italy. We had support from two small companies (one is kringlan.ch, which is pretty interesting in terms of manufacturing processes) for the engineering and can use an autoclave at our university which is a great help anyway!.

It`s definetely more critical than a monocoque...

And Clenn: It`s only 5 kilometres to swim to the swiss border from Immenstaad. We should arrange something next year! Did you also make your really, really fantastic monocoque there?

[JR @ CFS]

Chalmers has been working on theirs since 2003, getting progressively lighter and stiffer, but still suffering flexing problems. I seem to remember that Pats Corner on www.formulastudent.de has a piece about flexing wheels.

[J.R.]

Darmstadt,

Did you have any problem with loss of tyre pressure due to the way you mounted the valve? Carol Smith warns against mounting the valve pointing directly to the center of the wheel, stating that the centripetal force will open the valve during operation, and I was wondering how this actually plays out a FS velocities?

Car looks great, glad to see you got to use the rims at Hockenheim!

[PSUAlum06]

the other issue I've heard of with student designed or fabricated wheels is out of spec rim flanges. You don't have to be too far outside of the ETRTO or TR&A guidelines to be at the point where it either takes 90 psi to get your tires to seat or your tires just don't stay attached to the wheel.

[exFSAE]

CF wheels.. sketchy at best.

[murpia]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by J.R.:
Darmstadt,

Did you have any problem with loss of tyre pressure due to the way you mounted the valve? Carol Smith warns against mounting the valve pointing directly to the center of the wheel, stating that the centripetal force will open the valve during operation, and I was wondering how this actually plays out a FS velocities? </div></BLOCKQUOTE>
This is one of the reasons to always fit a valve cap. The good ones are o-ring sealed.

Regards, Ian