u401768
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posted on 20/5/05 at 07:49 PM |
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Aluminum honeycomb chassis
I have been looking around for a while, with the plan to build a mid engined BEC style car from scratch and have been debating using 26mm Aluminum /
honeycomb panels. They are easy to work, joint’s like wood (tongue and grove) Very strong/light and you can glue it together (see Hexcel composites
for details). I have added a PDF of a similar idea. What are ever ones thoughts - has possibilities or a non hoper?
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colibriman
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posted on 20/5/05 at 08:22 PM |
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well this fascinates me...I'm about a third of the way through reading the article/paper..........reading it all will take a while!
need a bike engine? - www.colibriman.com
SVA ready Mk Indyblade possibly for sale.....if the offers good...!
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zilspeed
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posted on 20/5/05 at 08:40 PM |
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The centre section of the Stratchcarron uses honeycomb plank construction, as does the Formula Vauxhall Lotus chassis and the clubmans chassis
built by Lola designer Ben Bowlby (sbject of an equinox programme on the tv - remember that ?)
This was when everyone else was building spacframes.
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ceebmoj
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posted on 20/5/05 at 08:57 PM |
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hi,
as has been said ther ar a number of cars that are built using this tecneak however the Formula Vauxal Lotus cars are very simple 2 parelel planks
with a ally casking at one end and the gear box bolted on the other with two reol hopes in the midle. I can try and fined some pictures if you are
intrested.
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colibriman
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posted on 20/5/05 at 09:15 PM |
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having read through it a few things come to mind...
1. if you were to build it successfully, what would happen if it had damage to the chassis....would it be start again??
2. is the services of a CNC machine an absolute must for the chassis to be right or could it be done manually in your garage.
3. It states material cost of the chassis honeycomb to be around £560....it won't be a cheap build option.
4. if It all works...can I have one?
Not sure how an engineer type of person would view it but I'd like to know....
If your brave enough for a challenge and not skint...go for it
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SVA ready Mk Indyblade possibly for sale.....if the offers good...!
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Dusty
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posted on 20/5/05 at 09:38 PM |
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Alan Staniforth's excellent 'Race and Rally Car Source Book' (Pub: Haynes) shows this material used in building Terrapin monocoque
chassis with some detail on the method.
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u401768
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posted on 20/5/05 at 09:38 PM |
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My initially thoughts were just the same but looking round/read i cam up with the following:-
1) The chassis could be made using a router, and careful marking, cutting, and bending - in terms of the accuracy, it should be as easy to build as
welding as chassis. Modern epoxy resin is very adaptable.
2) the cost would be more than a steel chassis, but would not need paneling etc, so should only be in the region of £200 - more but not
unaffordable.
3) In the event of a crash, the structure would stand up very well, but I’m not too sure if it would be a rebuild or not. You should be able to joint
in new sections.
I would be interested in the formula Vauxal. It was also used by most of the F1 cars in the late 70 – They found it quick/easy and very strong in the
days before military budgets and technology.
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colibriman
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posted on 20/5/05 at 09:53 PM |
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I certainly think it's worth looking into.....have you priced the panels to get the £200 or is that an estimate...
The diagrams in the paper certainly made it look straightforward, but what happens when it comes to attaching suspension etc....I wasn't really
understanding how that's tackled....
This is interesting stuff...
need a bike engine? - www.colibriman.com
SVA ready Mk Indyblade possibly for sale.....if the offers good...!
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Noodle
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posted on 20/5/05 at 11:34 PM |
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I opened a discussion on this before. Didn't get anywhere though.
Fascinating subject!
http://www.locostbuilders.co.uk/viewthread.php?tid=11820
Cheers,
Neil.
Your sort make me sick
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colibriman
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posted on 21/5/05 at 08:19 AM |
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I never saw that one....as you say it kinda dries up....
need a bike engine? - www.colibriman.com
SVA ready Mk Indyblade possibly for sale.....if the offers good...!
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WIMMERA
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posted on 21/5/05 at 11:13 AM |
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Do a google search on PRB composite.
Wimmera
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colibriman
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posted on 21/5/05 at 12:17 PM |
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had a look at PRB and it sounds pretty good..no mention of price though.
need a bike engine? - www.colibriman.com
SVA ready Mk Indyblade possibly for sale.....if the offers good...!
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Mix
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posted on 21/5/05 at 03:22 PM |
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I have experience of aluminium honeycomb panels as used in aircraft.
They are light and rigid. However they are always used as structural panels within a structural framework.
Personally I would have serious doubts over the integrity of the joints shown in the PDF and certainly have never come across an instance of major
loadpaths being fed directly through this type of material.
As mentioned before, the only method to repair damage is to remove and replace it.
Just my experiences and feelings
Mick
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u401768
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posted on 22/5/05 at 07:04 PM |
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A few years ago (well about 15) I did a Uni project with a fried, where we designed a car using this kind of principle. It was to use a Alfa boxer
engine/BMW K100, and was very similar looking to Taydec in looks. The main structure was using a Ali/honeycomb floor, with 2 very deep (aprox
400x400mm box sections down each side. These carried the suspension loads (A frame/trailing link) and air to the rads. Also it only weight in at
380-400 Kg. The main benefit we found, was the in crash - rather than bending/collapsing the structure progressively failed in the local area. As
previously stated, in the event a crash, the chassis would be written off, but it should be very quick/easy to build a new one and as an other all %
of the investment in a car of this type the martial cost relatively low. With some careful design/though i would think the structure could be made in
2 or 3 major units (front, rear, survival cell) which could dramatically increase safety, and also make repairs possible.
I would think something along the lines of Taydec/Aeon spyder/AGM WLR would lend them self’s to this type of design or even a car like the fisher
Fury to replace the floor and side pods with a strong box section structure that would dramatically increase the torsion stiffness with out a big
increase in weight but also increase the side impact safety. The main thing is to have a design where you can use deep/wide box sections. Fastening of
suspension would need the use of ali top hat/large diameter bobbins to be bonded through the structure to pass the loads to the skins and take care of
the compression loads. The use of a hybrid chassis design could be used (space frame rear honey comb front)
The cost would be higher, but should not be too dramatic, but would the advantages make it worth while. As an alternative would it be worth using in
a standard 7 stile chassie design, to replace the triangulation, side panels and floor?
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britishtrident
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posted on 22/5/05 at 07:25 PM |
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This class material has be around for a very long time but the fact it has been used in very few cars in spite of its tremendous stiffness to weight
must tell you something. F1 used for a while in the Lotus 79 era but quickly turned away from it when carbon composites came on the scene. I know
Charles Barter built a hybrid Davrian Imp with honeycomb structure for hillclimbs back around 1980 but it wasn't as sucessfull has his car with
the standard Davrian grp monocoque.
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clbarclay
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posted on 22/5/05 at 08:53 PM |
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I meet a person in a 'little thief' car park near Shrewsbury today, he was towing a trailer with an aluminium honey comb tub on it. The tub
it turnd out was for a Strathcarron sports car. He said they cost about £3000 new, his cost £250 curtesy of good old ebay.
http://www.strathcarron-sports-cars.com/
The strathcarron looks to use a aluminium tub, with steel space frames attached at each end. Pivtured bellow is a Strathcarron tub.
Rescued attachment Strathcarron tub.JPG
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Volvorsport
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posted on 23/5/05 at 12:08 AM |
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davrain/darrian monocoques rule !!!!
extremely repairable , and strong , and durable .
youll have to go some to beat it on material cost aswell
of course im biased
www.dbsmotorsport.co.uk
getting dirty under a bus
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WIMMERA
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posted on 23/5/05 at 12:58 AM |
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Colibriman, they have a nice little line on one of the sites " PRB will only be supplying this car to those who can prove a competition heritage
and who are not fazed by the premium price"
Wimmera
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colibriman
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posted on 23/5/05 at 07:24 AM |
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need a bike engine? - www.colibriman.com
SVA ready Mk Indyblade possibly for sale.....if the offers good...!
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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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Paul_C
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posted on 24/5/05 at 07:46 PM |
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Aluminium Honeycomb
Interesting paper and respect for the effort involved though I don't know how practical the particular configuration shown in the 3D computer
model is. Where do you sit and how do you get in ?
Race Tech magazine (www.racetechmag.com) has been featuring a build of a single seater motorcycle engined hillclimb car that uses an aluminium
honeycomb tub with a spaceframe rear section holding the engine and transmission.
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ERP
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posted on 25/5/05 at 12:46 AM |
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quote: Originally posted by Volvorsport
davrain/darrian monocoques rule !!!!
extremely repairable , and strong , and durable .
youll have to go some to beat it on material cost aswell
of course im biased
I assume they use some sort of composite monocoque?
Is it just ordinary GRP or something more exotic?
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Alaric
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posted on 25/8/05 at 04:49 PM |
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Hi There,
An interesting read through this thread..... I manage my farthers company which manufactures Ali Honeycomb panels amongst other composite
materials.
The PRB looks like a louts 7 / caterham clone & actualy the caterham does have some honeycomb panels in it. I know, we make them ! They are used
mainly for crash impact safty in the sides and in the boot for a weight reduction.
As a side, honeycomb is starting to become common place in a lot of modern road cars. Partialy crushed honeycomb structurs can be acturatly predicted
and absorb a large amount of energy, as such they are being used in the head lining around the driver and pasenger for impact absorbtion.
It is true that the F1 uses carbon, but they also use honeycomb in places, typicaly an arimid called Nomex. Its a resin dipped dupoint fiberous paper
core, typicaly used for its fire rating as its self extinguishes. The core is laminated into mouldings and vac bagged to produce a shaped lightweight
peice. Alas this requires tooling to form the mould and hence is inheriantly expensive for a one off, let alone the material costs.
cya,
Lee
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Volvorsport
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posted on 25/8/05 at 05:50 PM |
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well , if any of you are at brands hatch on sept 17th ill be there showing off my integral kevlar/grp tub .
darrians are built to spec and just plain ole grp and woven roving was plenty durable enough , kevlar/carbon was added in local spots for
reinforcement .
i believe one of the aus cars uses an ally honeycomb construction - the closest person to me who uses this ally honeycomb technique is pilbeam in
their SR2 car .
www.dbsmotorsport.co.uk
getting dirty under a bus
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cymtriks
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posted on 4/9/05 at 08:02 AM |
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The cost of honeycombe looks alarming until you realise that you can buy it ready cut and just slot it together. No cutting to length, no filing of
joints to get a good fit, no distortion during welding.
Of course "ready cut" is even more expensive than uncut but when it all arrives it'll be like assembling a flat pack.
I actually discussed this type of chassis with someone who used to supply autoclaves for composite tubs to the racecars business. He was building his
own design of spaceframe chassis for a race series and had asked me to do some FE on it. He reckoned that by the time you included your, or an
emplyee's time, you were better off with a pre cut flat pack honeycombe chassis.
Interestingly he reckoned that a good spaceframe in this race series had around 3500 ftlbs per degree of stiffness while the honeycombe ones were at
about 5000 ftlbs. He didn't tell me this before I did some concept analysis which gave much the same results for spaceframe and honeycombe
versions of his car!
The crash resistance is higher but the repair is impossible or very tricky. It's probably new chassis time if you have a crunch.
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Triton
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posted on 4/9/05 at 03:26 PM |
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Try this site for honeycomb ali chassis..........www.rallysportreplicas.co.uk
But don't take it too seriously though it might just be a figment of somebody's wild imagination
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