Carbon monocoque

Urs · 01-07-08, 01:19 PM

hello
what do you think about carbon monos

Murray Cowley · 01-07-08, 01:32 PM

Expensive ?? !!

Bill Musarra · 01-07-08, 01:38 PM

I think they will have trouble driving the space frames as well!!!!

Bill

Urs · 01-07-08, 02:16 PM

what could be the problems?
what is the weight of an original chassis?
i think a light car is very important.

Russ Noble · 01-07-08, 02:37 PM

Urs,

I agree with you about weight. I'm sure I've read somewhere that carbon fibre when used in a structural application has a limited life expectancy.

Maybe someone experienced with these composites would care to comment?

Bill D · 01-07-08, 02:45 PM

I woould rather see titanium

Ian Anderson · 01-07-08, 03:11 PM

I think it i a great idea and will be light

Also the strength should last and Ascari are already making Carbon chassis for their road cars

Here's a pic of their car when the GT40 clubs visited about 2 years ago

Ian

EGLITOM · 01-07-08, 03:56 PM

Could make a strong and lightweight structure.
If it is used the correct way and proper UV light protected it also should last.
Another good example for it is the porsche Carrera GT.
I have some great pictures of there chassis. as soon as i find out how to post here i will do it.
TOM

EGLITOM · 01-07-08, 04:20 PM

Looks familiar or !

What do you think ? looks close ha

@ron pictures are linked

TonyM · 01-07-08, 11:19 PM

Hi,

About a year ago I saw a 40 for sale that said it had made extensive use of carbon fiber, not sure if it's the whole moncoque or just panels.. I had one picture that I'd saved for reference.

Chris_K · 01-08-08, 12:44 AM

I believe that was the GT40NZ car (but may be wrong) which is a tube frame with the carbon paneling.

It was a gorgeous looker though!

Urs · 01-08-08, 02:33 AM

Hello Russ

I think the durability also because UV and fatigue should be not insolvable.the first thing ist to place the layers in the right way.
There are 1000 of sailplanes which flying thousands of hours in the sun i think the temperature could be a problem.
When you have carrying part on a plane that you wanna do in composit
then you have to do a load test and you have to heat up the part to 80 degrees. When the test is ok you can do a dark paint on the surface.

We also have passenger planes that are made of carbon.

sorry for my english!!

Keith Hardy · 01-08-08, 02:58 AM

Quote:

Originally Posted by ckouba

I believe that was the GT40NZ car (but may be wrong) which is a tube frame with the carbon paneling.

It was a gorgeous looker though!

Wasn't it the GTNA car? A member here bought it and then the company folded. It had Eric Broadley's son involved with it I believe...

Chris_K · 01-08-08, 06:01 AM

Quote:

Originally Posted by Keith1

Wasn't it the GTNA car? A member here bought it and then the company folded. It had Eric Broadley's son involved with it I believe...

Whoops, that was the one I was thinking it looked like. Told you I could be wrong. It was in Indiana or something and there was a white with blue sister car.

Mike Dozier · 01-08-08, 12:48 PM

Many mono customers are not looking for less weight....they are looking for authenticity
to the original chassis design, so welded steel (or SS) is preferred.

Actually I'm surprised more GT40 manufacturers don't offer carbon fibre bodies.
As I recall....Factory Five Cobra offers a CF body that weighs 1/2 the fiberglass weight.

Fran....have you calulated what the price adder would be to offer a CF body ?
How much weight would you save?

MikeD

Big-Foot · 01-08-08, 01:26 PM

Factory Five only offered a small number of the CF Bodies.. I think all you can get now are dashboard, spats, doors and trunk lid in CF..

CF has terrible impact resistance and is actually quite brittle - I don't think I would want a pure CF tub unless it were reinforced with Kevlar and/or honey-comb..

EGLITOM · 01-08-08, 06:08 PM

@Randy
They way to go would be definetly to laminate with strucural supporting materials. like ALUMINUM Honey combs or foams etc. Regarding a crash stability there should be no issue if done right ( just think about formula 1 monos).
@MIKE
totally agree to you, if you are looking for a car which is as close to the original as possible.
But on the other hand you could built a car with superior structural stability with app 200 # less ( Mono plus body ). This combined with a full alloy engine should give a car < 2000 #, put some 18"ers on it with modern high performance tires and a lightweigth 350 mm racing brake and on and on and on JUST DREAMING

would certainly be a nice and fast car. But also would cost a small fortune in design and development.

FRPGUY · 01-09-08, 08:14 AM

I get requests now and then asking if I could make a GT40 body in carbon fiber. When I work up a price, that's the end of it! The price doesn't justify the weight savings to most people.
The trouble FFR had and as do all fiberglass fabricatores using a "wet layup" system, the material is black and you can not see any air voids behind the fabric when laying it in the mould. With FFR Roadster body I had, the amount of body putty I had to use to fill all the air voids made the body weigh more than a fiberglass body. Kevlar has to be vac. bagged. It's pretty tough to lay up Kevlar using a "wet layup" system. It just doesn't work like most fiberglass products when using polyester resin. Kevlar works best with epoxy resins and the same with corbon.

Miles · 01-09-08, 08:32 AM

Just out of interest how much extra would it add in cost for a carbon body?

Hawk Cars, Hawk Cars - HF2000/HF3000 Price List offer an epoxy kevlar option on their stratos replica and this is priced at an additional £2,250-00 plus VATwhich to my mind doers not seem prohibitive.

I did see an example of this on a v8 bike engined Stratos prepared by Cyclone and the quality of the wet lay up did look to be very good (obviously i only saw the internal surfaces as the exterior had been preped and painted!

Obviously this is far simpler than a carbon monocoque. I suspect carbon body panels has more to do with being able to say "carbon, epoxy and kevlar" in preference to "polyester and mat". i.e bench racing.

The one point wehre i thought it might work very well is in the roof panel. I have been suprised to read of the problems peole have had with this sagging priro to instalation of the windscreen and i would have thought that carbon epoxy would have sufficient integrity to resist this.

If anyone could make a double skined epoxy carbon roof with a honeycomb core then I can see real benefits, (pressumably one could then do away with a roll cage?). In practice this could only be too expensive. One could quite economically use a foam core though...

Just some idle thoughts on the subject!