URGENT HELP - Glasswork / GRP / etc.

joeldking

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Hia

Unusual request for you...

Nothing to do with boats (except that I share sponsors with the Airwaves / Claygate powerboat team).

I race Streetluge, an extreme sport similar to the winter Ice Luge, but done on the road. Last year I was national champion and this year I am attending several World Cup rounds. I am also atempting the World Record for a powered Streetluge using a miniature jet engine.

I have had a special new luge chassis I have built, but need help moulding some fairings round it. If you are competant with glas/carbon/kevlar fibre or GRP and live in the Sussex/Hants area PLEASE HELP!

Please follow this link to get an idea of what I'm after:
http://www.chrismcb.com/streetluge/boards/bodywork.htm

My website is:
www.GravityKing.co.uk

Many thanks in advance.

Joel
 

ronsurf

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Hi Joel - I think streetluge would be more akin to motorcycling - have you tried any motorcycle scrappies, backstreet bike shops etc to locate a bike fairing you can modify? Much easier than fabricating one from new... If you have no joy, i can PM the name of a friend at Plymouth Uni who is a composite freak and would probably be willing to help you. But he's in Plymouth....!

D
 

joeldking

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Thanks, keep the suggestions / offers coming.

Unfortunatly motorcycle fairings are completly the wrong shape. The fairing would basically be one or 2 pieces, moulded and bonded to the chassis. See the above link to see what I mean.

I'll try that company.

Thanks

Joel
 

William_H

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The primary difficulty you have is that really good fibreglass work comes from forming it in a mold. The mold can take 20 times as long to produce than the final fairing off the mold. Hence fibreglass work is really good for doing many copies but not good for one off.
You can do a flimsy rough mold more easily for one off but then you will have to put a lot of work into the finish of your fairing.

I notice that some of the fairings are obviously carbon fibre rather than glass fibre. Don't let that meterial put you off Carbon and Kevlar are just like fibreglass to use but can be thinner and stiffer for carbon or thinner and tougher for Kevlar. Carbon is balck Kevlar is yellow.

So I can only suggest that unless you have very generous sponsors that you start experimenting with production yourself. And don't expect showroom results without a huge effort. good luck olewill
 

ShipsWoofy

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You are going to put a jet onto a what is essentially a big tray..

I wish we had a black border mark up for these messages!

You are either very brave or a total nutter!

Anyways, is it just the nose-cone you are after, then surely you will be after carbon-fibre or kevlar materials, need to protect your pins. I think your may be heading into a specialist area here beyond the competence of most, including myself who are what you may call competent with GRP.

I presume you need as much strength as possible with as little weight?

I do wish you the best of luck and hope you manage the record. Please don't kill yourself trying though!
 

ShipsWoofy

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Really?

I thought you had to bake carbon fibre and keep it under x pressure while working it, I always thought it was beyond the average amateur to use.
 

jhughes

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I used to work for a company that did Carbon fibre composites (Formula 1 race car cockpits, mudguards for rapier rocket launchers and SAS grappling hooks) and they were all vacuum bagged and placed in an oven.
 

boatbuilder

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As will H says carbon is ni more diffivult than glass. Allthough we use carbon and kevlar in big mouldings , small ones are done on the bench and not with a bag.
The reason that they are cooked is to post cure the epoxy, as wich must be used with carbon to keep the productlight.
 

William_H

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To explain about the "must cook" for carbon fibre.
Much of the carbon fibre material especially for aviation manufacture comes in the form of "prepreg" that is short for pre- impregnated.
Here the epoxy with hardener is mixed and rolled into the carbon cloth to ensure precise ration of resin to carbon fibre. This mat is then cooled and remains refrigerated until it is used in a mold.
the mat is laid out in the mold. The vaccuum bags are attached to ensure that the layers are pressed together and excess resin is squeezed out to a sacrificial blotter layer. The whole then is cooked to harden the epoxy.
This method gives very accurate quality control in that it does not vary in epoxy content ratio and gives the strongest lightest and reliable product. You can however imagine the logistics difficulty of keeping rolls of mat at a set low temperature for months durig transport from USA to Australia. You need temperature monitoring gear in refigerated containers and even then wastage can be huge due to cooling failure. The material is usually purchased in large lots.

Carbon fibre can however be bought just as a dry cloth and you treat it like glass using polyester epoxy or vinyl ester resins.
olewill
 

boatbuilder

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We use dry cloth mainly as we make one off boats on male moulds. We use a mangle towet out the carbon then lay up and bag.
Biggest job 60ft carbon cat hull .
We rarely use pre preg as it needs so much plant to keep it cool and then hot.
We cook finished boats at about 45C for 24hr /forums/images/graemlins/smile.gif before paint .
 
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