marc n
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| posted on 29/10/06 at 05:01 PM |
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dick bear
stunning bodywork, a real talent you have mastered there congratulations
please email rather than u2u
direct workshop email ( manned 8am till 6pm )
www.mnrltd.co.uk enquireys to :-
chrismnrltd@btinternet.com
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NOTE:This user is registered as a LocostBuilders trader and may offer commercial services to other users
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gttman
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| posted on 29/10/06 at 07:39 PM |
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Kb your comments seems pretty harsh to me.
Andygtt
Please redefine your limits
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JoelP
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| posted on 29/10/06 at 07:41 PM |
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someone has deleted the post that kb was responding to - its not as bad as it might sounds now it looks like a rant about nothing! 
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gttman
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| posted on 29/10/06 at 08:03 PM |
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OK cheers I did find it a bit puzzling.
Andygtt
Please redefine your limits
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geoffreyh
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| posted on 30/10/06 at 10:13 AM |
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I think both Kurt and Dick have had some stressy days lately and therefore I think the discussion took a wrong turn. I've been reading on
different fora and websites about this issue and I think everybody knows what to do.
We can't forget what both Dick and Kurt did those last years. They both showed us incredible workmanship in their own specialties.
There are of course a lot of others who did similar excellent jobs
Geoff
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ZEN
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| posted on 30/10/06 at 09:41 PM |
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Realy imressive build!
My YouTube channel Cars, bikes - track days, motorsport, sim racing and more.
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RallyHarry
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| posted on 31/10/06 at 01:32 PM |
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What is the weight penalty for using metal vs fibreglas ?
Roughly in %
Cheers
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kb58
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| posted on 31/10/06 at 02:29 PM |
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It depends if it's structural and how much load is on it. It also depends how the composite is made - parts made with a chopper gun are cheap
but heavy because there's so much epoxy in it.
Somewhat related, material choice also depends on the environment. My carbon shell had to be painted with a light color paint. That's because at
the desert race tracks, the heat of the sun can actually soften the epoxy. OTOH, aluminum work-hardens and will eventually crack. It's all a
trade-off.
[Edited on 10/31/06 by kb58]
Mid-engine Locost - http://www.midlana.com
And the book - http://www.lulu.com/shop/kurt-bilinski/midlana/paperback/product-21330662.html
Kimini - a tube-frame, carbon shell, Honda Prelude VTEC mid-engine Mini: http://www.kimini.com
And its book -
http://www.lulu.com/shop/kurt-bilinski/kimini-how-to-design-and-build-a-mid-engine-sports-car-from-scratch/paperback/product-4858803.html
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Fred W B
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| posted on 31/10/06 at 02:43 PM |
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You can use a density factor of 8.07 for steel, 2.73 for aluminium, and very roughly 1.7 for conventional hand laid fibreglass.
So for the same mass, you can have a 1 mm thick steel part, a 3 mm thick ally part or an 5 mm fiberglass part.
Cheers
Fred W B
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Alan B
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| posted on 31/10/06 at 03:37 PM |
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quote:
Originally posted by kb58
........parts made with a chopper gun are cheap but heavy because there's so much epoxy in it...........
Nit picking, maybe, and I could be wrong, but wouldn't most cheap and cheerful parts made with a chopper gun be using the much cheaper polyester
resin?
Polyester is also relatively dense/heavy, which still makes your point valid.
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kb58
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| posted on 31/10/06 at 03:54 PM |
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Right you are!
Mid-engine Locost - http://www.midlana.com
And the book - http://www.lulu.com/shop/kurt-bilinski/midlana/paperback/product-21330662.html
Kimini - a tube-frame, carbon shell, Honda Prelude VTEC mid-engine Mini: http://www.kimini.com
And its book -
http://www.lulu.com/shop/kurt-bilinski/kimini-how-to-design-and-build-a-mid-engine-sports-car-from-scratch/paperback/product-4858803.html
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violentblue
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| posted on 1/11/06 at 12:38 AM |
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I used to build boats (and even the odd surfboard) years ago. it is more labour intense to lay fibrelass weave rather than give it a good healthy
layer of chop. but we could build a boat almost half the weight, but just as strong, or even stronger, by hand laying different weaves and thicknesses
of cloth. and thats without exotic materials.
built one kevlar reinforced river boat, that was many magnitudes stronger with no weight gain.
wish I had oppertunity to work with carbon fiber, but never did
a few pics of my other projects
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Dick Bear
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| posted on 1/11/06 at 08:11 AM |
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Weight question
RallyHarry,
It is nearly impossible to give you a % figure for weight advantage using Fiberglass and metal because, as has already been said there are different
methods of Glassing. Further, there are many different types of metal used to fabricate body panels. Even within the Aluminum family there are
numerous different alloys each one having different weights, strengths and workability characteristics within a single gage.
The typical steel used for today’s body panels is 18 or 19 gage. If you are restoring an old vehicle the thickness necessary to match the original,
in most cases, is much thicker. For hand shaping each of the component panels of the McBearen I used .063/3003 aluminum alloy due to its’
workability. If shaped properly this should last indefinitely.
Dick Bear
www.marketpointproductions.com
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cossey
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| posted on 1/11/06 at 09:18 PM |
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quote:
Originally posted by kb58
It depends if it's structural and how much load is on it. It also depends how the composite is made - parts made with a chopper gun are cheap
but heavy because there's so much epoxy in it.
Somewhat related, material choice also depends on the environment. My carbon shell had to be painted with a light color paint. That's because at
the desert race tracks, the heat of the sun can actually soften the epoxy. OTOH, aluminum work-hardens and will eventually crack. It's all a
trade-off.
[Edited on 10/31/06 by kb58]
epoxy is thermoset so if it has been properly postcured it cant be softened it will just decompose
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kreb
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| posted on 2/11/06 at 12:48 AM |
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Out of curiosity, does anyone use foam core or vaccum bagging on auto bodies? I've seen some simply incredible strength-to-weight ratios
acheived with epoxy/Kevlar/foam core/vacum bagging.
Chopper guns are extremely blunt instruments. I'd be embarased to use one for most projects that I'd be involved in.
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kb58
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| posted on 2/11/06 at 04:34 AM |
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quote:
Originally posted by cossey
quote:
Originally posted by kb58
It depends if it's structural and how much load is on it. It also depends how the composite is made - parts made with a chopper gun are cheap
but heavy because there's so much epoxy in it.
Somewhat related, material choice also depends on the environment. My carbon shell had to be painted with a light color paint. That's because at
the desert race tracks, the heat of the sun can actually soften the epoxy. OTOH, aluminum work-hardens and will eventually crack. It's all a
trade-off.
[Edited on 10/31/06 by kb58]
epoxy is thermoset so if it has been properly postcured it cant be softened it will just decompose
I used West Systems epoxy and their engineer says their epoxy will soften at around 130-150deg F. While technically you're correct, about epoxy
softening above the cure temperature, who here does post-cures? I left out that detail because, in our Locost context, it simply doesn't
apply.
For real-world examples, how many composite aircraft are painted black? There are composite cars with dark colors, but with $millions, you can do such
things. For us it's not part of our world.
[Edited on 11/2/06 by kb58]
Mid-engine Locost - http://www.midlana.com
And the book - http://www.lulu.com/shop/kurt-bilinski/midlana/paperback/product-21330662.html
Kimini - a tube-frame, carbon shell, Honda Prelude VTEC mid-engine Mini: http://www.kimini.com
And its book -
http://www.lulu.com/shop/kurt-bilinski/kimini-how-to-design-and-build-a-mid-engine-sports-car-from-scratch/paperback/product-4858803.html
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Browser
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| posted on 7/11/06 at 06:10 PM |
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Come on Dick, where's the next update then? I was hoping to see it'd been finished, painted and had blown away some wannabe 'The
Fast And The Furious' pilot in his overblown Civic
By the way, stunning car and stunning metalwork
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Dick Bear
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| posted on 16/11/06 at 05:18 PM |
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McBearen Update
Hey Browser...
I don't know if you seen the latest updates but I made the last one (actually 2) today.
http://metalmeet.com/forum/showthread.php?p=67421#post67421
You can check them out at the above address.
Thanks for your interest.
Dick Bear
www.marketpointproductions.com
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Syd Bridge
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| posted on 16/11/06 at 05:45 PM |
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Post Cures???
I post cure everything that needs top numbers. But it needs to be the right resins to start with.
Strength/weight. Depends on application.
Stiffness. Can't beat nomex core with a thin skin of something. Ali honeycomb maybe, but depends on application again.
Vacuuming a wet layup can have benefits, but forget it with prepreg, unless it has a very high resin content, which sort of defeats the purpose
really.
Do I know what I'm doing? Sort of. Been playing with carbon since 1974, when it came in single tows!! Using 'composites' since I was
a nuisance under Grandad's feet! And run my own autoclaves.
Cheers,
Syd.
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kb58
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| posted on 16/11/06 at 07:18 PM |
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I didn't mention prepreg because I thought virtually no home car builders used it.
Mid-engine Locost - http://www.midlana.com
And the book - http://www.lulu.com/shop/kurt-bilinski/midlana/paperback/product-21330662.html
Kimini - a tube-frame, carbon shell, Honda Prelude VTEC mid-engine Mini: http://www.kimini.com
And its book -
http://www.lulu.com/shop/kurt-bilinski/kimini-how-to-design-and-build-a-mid-engine-sports-car-from-scratch/paperback/product-4858803.html
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Dutchman
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| posted on 17/11/06 at 01:31 PM |
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this is a dream ...
best project that I've seen , bring some ideas 
Tarzan English with foreign accent!
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madman280
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| posted on 24/11/06 at 04:13 AM |
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Dick, very nice work, your a very talented craftsman.
Don't take the critisism too hard. Opinions are like ass holes ..everyones got one...and its never pleasant when you hear someone elses.
A man who has not made any mistakes is someone who has done nothing. Making mistakes and learning from them is part of the creative process.
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MG David
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| posted on 24/11/06 at 09:56 AM |
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More than relative density, strength and stiffness
Going back to Rallyharry's question about relative density etc. I think there are other factors to consider as well when deciding what material
to build a body out of.
Build speed/practicality and surface quality are very important, as is cost.
Taking Dick Bear’s excellent car as an example, he has made rapid progress using aluminium and has achieved a good surface quality. To build the same
body out of GRP he would have either have had to have a mould or he would have had to build it from foam sheet and then laid up GRP on both sides. The
outer surface would have been the back of the lay up so there would have been further work in achieving a surface good enough to paint. So when
comparing weight we need to remember the weight of a good thick coat of spray putty.
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madman280
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| posted on 25/11/06 at 03:54 AM |
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Talk about inapropriate and off topic. To go on about fiberglass construction in reply to a post about a guy who can do REAL aluminum body work is
just rude. I'd rather have my lotus replica's body all aluminum. I'd polish it and show it off. Anyone can do fiberglass..it takes
talent to do aluminum. Give the guy some respect.
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kb58
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| posted on 25/11/06 at 08:31 PM |
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quote:
Originally posted by madman280
I'd rather have my lotus replica's body all aluminum. I'd polish it and show it off. Anyone can do fiberglass..it takes talent to do
aluminum. Give the guy some respect.
Last I read he was going to paint it. Seems a shame.
Mid-engine Locost - http://www.midlana.com
And the book - http://www.lulu.com/shop/kurt-bilinski/midlana/paperback/product-21330662.html
Kimini - a tube-frame, carbon shell, Honda Prelude VTEC mid-engine Mini: http://www.kimini.com
And its book -
http://www.lulu.com/shop/kurt-bilinski/kimini-how-to-design-and-build-a-mid-engine-sports-car-from-scratch/paperback/product-4858803.html
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