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U good with CAD?

Siduna - 26/8/14 at 07:07 PM

Help with car body design wanted!

I’m designing and building a mid engined car with a bike engine. I have a CAD software but having been out of the “CAD-software-use” for some years the modeling speed isn’t what it used to be.
Therefore I´m looking for help to design the body, which I will make out of carbon fibre and epoxy. Not new to making molds and vacuum infusion.

Is there anyone out there interested in helping out? I might be able to help you out with something?

Sam_68 - 26/8/14 at 07:37 PM

Whereabouts are you, and what CAD software are you using?

How complex is the body - are we talking an open car with no doors or windscreen, or a coupe with doors, for example?

balidey - 26/8/14 at 07:59 PM

Not wanting to knock your idea, but if this is a one off project then your time would probably be better spent on sketches and scale models. Forget the CAD part of it.
To get a really pretty, unique, shape using CAD you really want to use surface modelling techniques and this is not easy. Or rather it is easy to do, but not easy to get stunning results from.
If this is just to try out several different 'looks' then you might find someone with Photoshop skills a better starting point.

Sam_68 - 26/8/14 at 08:12 PM

quote:
Originally posted by balidey
Not wanting to knock your idea, but if this is a one off project then your time would probably be better spent on sketches and scale models. Forget the CAD part of it.
To get a really pretty, unique, shape using CAD you really want to use surface modelling techniques and this is not easy. Or rather it is easy to do, but not easy to get stunning results from.
If this is just to try out several different 'looks' then you might find someone with Photoshop skills a better starting point.

I disagree; I wouldn't necessarily waste time 'sculpting' a photorealistic bodyshell in CAD using surface modelling techniques, but what I would suggest may be worthwhile is creating a set of orthographic drawings of the bodyshell, then turning them into a set of loft lines that can be used to cut templates to create an 'egg box' structure as the basis of the mould.

Something like this.

balidey - 26/8/14 at 08:54 PM

oh yes, I agree, its possible, fairly simple to achieve. Have done something very similar (but far more basic) in the past.
I may have appeared a bit negative, but mainly as we know nothing about the project. I assumed that it was a one-off special and I find that these sort of projects often get driven down the CAD, FEA, CFD route because its fashionable and the 'done thing', when often its better and quicker to have a few hours with pencil and pad.
Then these can be taken as the starting point for the next step.

Many people forget that C A D actually stands for something. The C and A are key. It is just one tool that can help the design. But actually getting the design in the first place is where the skill comes in. This is why some of the better looking kit cars (IMHO) have been styled by an expert, see the GTM cars as a prime example.

Good luck to the OP, hope you get some useful help.

Sam_68 - 26/8/14 at 09:09 PM

quote:
Originally posted by balidey...I find that these sort of projects often get driven down the CAD, FEA, CFD route because its fashionable and the 'done thing'...

I absolutely agree with you there: there's a tendency to spend months carefully modelling every nut and bolt in photorealistic 3D, when what you really need to do is create a simple set of fabrication drawings then just get on with it!

But as someone who's been a professional designer for over 30 years (long before CAD was available at a practical and cost-effective level), I do appreciate that there are some things it can do that are very worthwhile.

A lofted 3D model is useful not just for creating the buck, but because unless you're a very gifted and experienced draughtsperson, it can be very difficult to get a true understanding of what 2D sketches will really look like as a 3D form.

Irony - 26/8/14 at 09:15 PM

I am 3D designer and I have 14 years in using 3D visualisation software etc etc etc. It is NOT easy to design a car in any sort of computer software. Trust me on this. There is NO substitute for getting a piece of A3 paper and some pencils. Start sketching the car chassis and body on the paper. Draw the wheels and wheelbase reasonably accurately on the paper and sketch away. If you have access to a photocopier you can copy and reprint the best shapes/designs and then tweak them. Try to get a front, side and rear sketch done to the best of your ability. Then and only then put it into some sort of 3D visualisation software and try to create the car in 3D.

If you try to design straight into the computer you will get a limited design. Especially if you are not a absolute wizard with the 3D software your using. You will compromise the design to overcome your lack of skill with the software. In other words you will say to yourself 'I won't have it like that because I don't know how to model it'.