Over and Under or around the sides

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flynfrog
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Joined: 23 Mar 2006, 22:31

Re: Over and Under or around the sides

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greenpower dude reloaded wrote:Oooops, of course, Unfortunately it's very tail heavy.. I've looked in to changing that problem but there is not a vast amount we can do we are really pushed for any useful space in this car. I haven't put it on the scales yet but at an estimate I would say that fully loaded it'll be about 120 KG 36kg batteries 44kg driver (you've got to love little sisters!) + 40kg car. All educated geusses. There is one battery directly infront of the rear axle and one directly behind there is also about 10KG of drive train not far behind that.

FL 20 FR 20

1100mm Wheelbase

RL 42 RR 38
you may want to look at moving some of that around or moving your body to the rear. You are most likely not going fast enough to matter.

marcush.
marcush.
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Joined: 09 Mar 2004, 16:55

Re: Over and Under or around the sides

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Credit is also due to MarcusH who mentioned channels previously, but i think this is a fair bit bigger than he meant.

haha is this my 3points lewishamilton input in case if you win the pot next year ,luke? :mrgreen: -oh forgot -it#s laura driving WW ....many excuses.

the channel is actually a lot simpler than my idea was ever going to be ,as I would have left the driver in her current height wich would of course have the effect of dividing the tunnel in the bum area ,where you sure would get a bit of unwanted business for the air to make its way with the two back wheels also in that area.Not sure if my idea would be just too fuzzy...but thanks for taking my ideas into consideration.

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greenpower dude reloaded
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Joined: 29 Dec 2005, 20:03
Location: Portsmouth, UK

Re: Over and Under or around the sides

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In all honesty It's developed this way and I never really planned a channel as such. I had considered your idea myself, but as you said it all gets a bit fuzzy travelling around stuff.

But several factors lead me down this route and I really love it, it looks great!! (I have the gift of being able to visualise a finished product) I'm hoping to get Solidworks over the next few weeks, which should allow me to try rounding everything off quite heavily, but in a sensible way don't worry guys! We'll see how much of a difference it makes to the Cd then take it from there. I think rounded off will improve it vastly in a crosswind, but it'll be interesting to see what difference it makes head on. If it raises it up by 0.01 but drops the Cd in a crosswind then it's probably worth it.

As much as I hate to say it, lets try and make it sexy now :P I grew up with the ambition of being a car designer, which is why Whoosh (the low blue one) was such good fun.
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RH1300S
RH1300S
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Joined: 06 Jun 2005, 15:29

Re: Over and Under or around the sides

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This is a great thread - I always read it when I logon....

I have a question, something just wandered through my mind looking at this.

If you are racing on a circuit, needing some sort of cornering ability - does ackermann have any effect on your design? I would assume you would want to consider that quite carefully to minimise rolling resistance when cornering.

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greenpower dude reloaded
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Joined: 29 Dec 2005, 20:03
Location: Portsmouth, UK

Re: Over and Under or around the sides

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Thanks for your kind words, I'm so pleased that people are enjoying this thread. I hope it gives you all some insight as to how exciting, challenging and rewarding such a project can be.

In my opinion, yes, Ackermann makes a vast difference. There are one or two good teams that don't use it but the majority do. Obviously it's only a factor towards a good vehicle but it is indeed something that makes a positive contribution towards the average speed.
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autogyro
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Joined: 04 Oct 2009, 15:03

Re: Over and Under or around the sides

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greenpower dude reloaded wrote:Thanks for your kind words, I'm so pleased that people are enjoying this thread. I hope it gives you all some insight as to how exciting, challenging and rewarding such a project can be.

In my opinion, yes, Ackermann makes a vast difference. There are one or two good teams that don't use it but the majority do. Obviously it's only a factor towards a good vehicle but it is indeed something that makes a positive contribution towards the average speed.
Do you have to use four wheels?

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greenpower dude reloaded
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Joined: 29 Dec 2005, 20:03
Location: Portsmouth, UK

Re: Over and Under or around the sides

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Unfortunately not, otherwise I'd have run one of our old Shell Eco Marathon Cars...

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autogyro
autogyro
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Joined: 04 Oct 2009, 15:03

Re: Over and Under or around the sides

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I am sorry.
Do you mean that the cars can only have four wheels?

marcush.
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Joined: 09 Mar 2004, 16:55

Re: Over and Under or around the sides

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autogyro wrote:I am sorry.
Do you mean that the cars can only have four wheels?
the regs even give a minimum track width....so no isetta layout.

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greenpower dude reloaded
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Joined: 29 Dec 2005, 20:03
Location: Portsmouth, UK

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So, with nearly 4months since our last update what's been achieved. Well I can assure you lots has been happening.

Although It feels i've neglected it, I can't ever seem to spend enough time on the project.

Anyway, Our next event is (all being well) 25th April for the Corporate Challenge against Prodrive, Bentley, Jaguar Land Rover and a few others. Following on from the form at our last event we are likely to do very well indeed.

Working with several really great people from this forum, notably Richard Smith of Symscape/Caedium http://www.symscape.com/examples/rans/c ... c-race-car I've come to a final shape. Over Easter I've started working on the buck. So far about 25/30man hours has yeilded a lovely shape.

We've knocked about 0.03 off the Fa and about 0.1 off the Cd so not bad at all.

Here are a few teaser images to give you an idea of what we've come up with. So far we are all chuffed as to how it's all come out and I just hope I can get the finish on the buck to give the shape justice.

Image

Image
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flynfrog
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Joined: 23 Mar 2006, 22:31

Re: Over and Under or around the sides

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you are really going to wish you had started sanding that about 30 min after you put all that bondo on it :lol:
Its going to be like sanding a rock now.

pick up a shurform for the rough stuff it will save you some paper

BreezyRacer
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Joined: 04 Nov 2006, 00:31

Re: Over and Under or around the sides

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flynfrog wrote:you are really going to wish you had started sanding that about 30 min after you put all that bondo on it :lol:
Its going to be like sanding a rock now.

pick up a shurform for the rough stuff it will save you some paper
That looks like clay to me.

Great to see you are making all kinds of good progress. Now remember, as you work to final shape the body that you should be thinking of how to leverage this success into your next project. If you get a job with a team, you'll have to invite me over too and show me the secret stuff!

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greenpower dude reloaded
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Location: Portsmouth, UK

Re: Over and Under or around the sides

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I know, it's always awful sanding these things down but it's so far not been too bad.

I like to try and find easy ways out when I'm working on projects. Firstly we knocked up a quick and easy (about 3hrs total)female mould, Hard board, Fibreglass for strength/joining and plastic sheet as release agent.

Filled this with polyurethane and rounded and hotwired this to a final shape.

We then covered this all just normal builders plaster. I couldn't resist the draw of £8.98 for 12.5kgs I'm sure I can get this smooth enough, it doesn't cost a fortune, doesn't go off too quickly but certainly sets fast enough.
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greenpower dude reloaded
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Joined: 29 Dec 2005, 20:03
Location: Portsmouth, UK

Re: Over and Under or around the sides

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Ahh forgot to say, Yes! It is all having a big impact on my next project. It's been a really great way to make a mould, so much easier than other methods i've tried.

I should also let you know the website has had a massive overhaul, www.horsfallracing.co.uk opinions please...
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flynfrog
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Joined: 23 Mar 2006, 22:31

Re: Over and Under or around the sides

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are you planning to pull a mold off of the plug or just pull a body off and pretty it up later?