Fred W B
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| posted on 15/10/04 at 08:55 AM |
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Midengined build in SA
Hi All
Having spent many lunch breaks over the last 2 years lurking on this site and following the various home built car sites on the net, allow me to
introduce myself and my project. Please excuse the length of this post but I am fascinated with the different backgrounds of, and influences on, the
various people involved in locost and similar projects and want to share in the fun. How some people find the time to keep a full on website up to
date while still keeping the family happy, building a car, and earning the money to pay for the toys, I don't know.
I am a 40 year old mechanical engineer and motor sport enthusiast in Port Elizabeth, South Africa and am in the early stages of building up a self
designed space frame two sweater mid engine sports car from scratch. The idea is to end up with a period looking late 60's CANAM style car to
use on the road for fun and possibly do some track racing, in our "classic" class out here.
I have been competing in two stroke karting at regional and national (SA) level for some time, but this year (2004) have taken a sabbatical so I could
devote all my spare resources (time and financial) towards getting a good start made on the practical side of the car project. That and I was getting
a bit tired of the apparently obligatory motorsport drama and intrigue between different competitors, and between the competitors, the organizing
bodies and other interested parties - the traders etc.
As for theory, I have some of the books (Staniforth, Smith, etc) and have spent a lot of time researching on the web, and am fascinated to see how
just a few theories, that you can see originate somewhere, pop up time and again, from different sources. Another excellent source is my 10 years
worth of back issue's of "Cars and Car Conversions" magazines. What I have leant from my involvement in Karting is that in every
field there are some people who can tell you what works, but very few who can explain why those things work. I prefer to listen to those that can
explain in terms that make engineering sense to me, and then make up my own mind.
I work at management level for a company (www.oddy.co.za) that manufactures bulk liquid transport equipment out of stainless steel, carbon steel,
aluminum and fiberglass, and so have experience with and access to suppliers of the sorts of materials and services which can be used in building
cars. South Africa has a strong car culture, so most things can be done, but those suppliers of specialist parts suitable for scratch built or race
cars seem to have been caught out by the recent strengthening of the South African Rand against US dollar, Euro and UK Pound, so it works out cheaper
to import stuff personally, particularly from the US.
With regard to facilities, I am lucky in that I have a large double garage in my back yard, which I have slowly equipped with tools. So for I have a
175 amp Hobart MIG welder, industrial drill press, 2kw Cut off saw, linishing machine, bench grinder, now up to 3 drill machines, 3 small grinders,
jig saw, orbital sander, sundry hand tools, taps and dies etc. I also built a carport (for my road car now displaced from garage, best to humor the
wife and let her park indoors) and a installed roll up door in the side of garage. May as well have light and air and a view of the garden while
working! Fortunately South Africa's climate is very conducive to outdoor activities. I have also built a flat build table on castors. This is
supposed to be fun, and I don't like to battle more than necessary. Still looking for a cheap small lathe. Fortunately I have a good friend (who
has spent 7 years on a very nicely detailed Cobra replica) who has a small engineering business so I also have access to a proper guillotine and press
brake. Although all this equipment and more is used at my day job, the scale of my company is such that it's not PC to get private jobs done at
work.
Following a considerable period of research and time spent outfitting my garage, actual work on the car in the garage started in early January 2004.
So how far have I got?
Chassis:
Fabricated partial mock up chassis in square and round steel tube, including removable (to get engine in and out) roll bar and bracing, full passenger
compartment, body framing and some of the side bracing on one side only. Still keeping my options open with regard to the wishbone inboard top mount
positions. The cockpit section of the chassis will be strengthened by fixing pressed up 2 mm alloy boxes to the sides with structural rivets, 1.2 mm
internal paneling, and 2 mm alloy floor, so it will end up looking like a monocoque centre section.
My intention is to get all the major components in place and the systems functioning in the mockup, and confirm the body fit, before I complete the
real chassis. I tend to overengineer things, so want to be able to stand back and look at the almost completed mock up before I make final decisions
on tube sizes and thicknesses. A spreadsheet with all the tubes detailed will predict the final chassis mass.
Drivetrain:
Bought early Rover 3.5 V8 engine (from Rover P6). While the cam is a bit worn, the rest looks pretty good, so this is good enough to build up around,
pending replacement or rebuild once the project is further along. This was temporally mounted to an Audi transaxle, from an early 90's 5
cylinder 500SE (these are very common is SA) in order to built the chassis around it.
Wheels:
Bought 2 off 7Jx15 and 2 off 8Jx15 steel wheels, had centers modified to suit chosen uprights, wheels repainted, part worn tires fitted.
Uprights:
Firstly cut down and modified Audi front uprights to attach wishbone suspension and get the KPI, castor angle and steering arm length I wanted, but
eventually decided it was getting a bit complicated, so bought some Ford Cortina front uprights (still lots of Cortinas on the roads out here). Rears
are heavily modified cut done Audi front uprights.
Suspension:
Bought enough rod end joints for one side of the car. Fabricated mock up front and rear wishbones of traditional pattern and mounted borrowed coil
overs on one side only, to see how it all fits together.
Steering:
Mini rack mounted in mockup, steering column made up with universal joints, kart steering wheel fitted.
Systems:
Made mock up V shaped fuel tank in wood (60 liter) and mounted in chassis between passenger compartment and engine. Held into chassis by removable
(from underneath) frame. Tank is shaped to allow engine to sit as close to passenger compartment as possible. The distributor ends up right behind the
passengers right shoulder.
Bodywork:
Originally, my planning was based on using a Lotus 23 replica shell, which somebody who knew somebody could get hold of somewhere. This didn't
work out, so I have now decided to go the whole hog and make a plug from scratch.
I have developed quite a thing for 60's full bodied sports race cars, so other sources of inspiration are Crossle 9S, Lotus 19, Brabham BT8,
Elva's, Can Am Mclarens's etc.
Once the decision to use the Rover V8 was made, the car got a bit bigger in order to fit every thing in, until I was up to a 2 400 mm wheelbase, the
same as a Lola T70 Spyder. So why not use the same track, and similar body proportions? So I have bought a 1/18 scale model of the T70 spyder I found
on Ebay. A colleague is currently digitizing this on a 3 axis measuring machine, and will scale it up in CAD in order to get a starting point for the
body. I plan to have plywood section ribs CNC routed, then go the ribs/stringers/foam/CSM skin/spray filler/etc buck route. I may then have the actual
mould made by one of my company's GRP suppliers. Still unsure if I want to try to do a close replica of the T70, or just use the proportions and
make a generic late sixties CanAm style body. In the meantime I have riveted some prototype side panels in alloy onto the mockup, as will be used on
the lower sides.
Seats:
Considering comments about body above, and use of an old motor, the project is leaning more towards keeping a "period" look, so I want the
seats to match. I have been unable to find any thing suitable, so have now made up a seat pattern in wood, two of which will be replicated in folded
ally and riveted in to the passenger compartment, before some padding is added.
So that is about it so far. The above list doesn't seem much for 10 months work, but a lot of decisions have been made. As those building non
book cars will know, you seem to hit points where you have to make choices on how you are going to do/make/position/size something, and as every
detail on the car is related to many other details, sometimes I grind to a halt. I then find it best to get on with some other area of the car, and
come back later to where the decision has to be made.
I am currently making up the engine to transmission adaptor plate/rear bulkhead, and getting everything in place I need to run the motor in the
mockup, that is real fuel tank, radiator, gearshift, clutch, some electrical bits, the exhausts etc.
As yet, still undecided on what to call my project. Any suggestions?
Cheers
FredWB
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swood
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| posted on 15/10/04 at 09:36 AM |
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mid engined build s/a
interesting project, build facilities sound first class, double garage with all that kit !!.
You will have to post some photos.
Have to agree about this web site, it is first class, I'm building an MK indy that some one gave up on, and a quick search give loads of
answers, or helps to make your mind up about the best way to tackle the next job !
good luck !
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mangogrooveworkshop
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| posted on 15/10/04 at 11:26 AM |
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There a company in Pietrmartzburg that makes the adapters and flywheels for your conversion.
Cant remember what they were called.
cant beat local knowlege!
[Edited on 15-10-04 by mangogrooveworkshop]
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Alan B
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| posted on 15/10/04 at 12:54 PM |
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Welcome aboard Fred......
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timf
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| posted on 15/10/04 at 01:28 PM |
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quote:
Originally posted by mangogrooveworkshop
There a company in Pietrmartzburg that makes the adapters and flywheels for your conversion.
Cant remember what they were called.
cant beat local knowlege!
[Edited on 15-10-04 by mangogrooveworkshop]
this lot are in sa and do some interesting convertion stuff http://www.giloeng.com/
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sgraber
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| posted on 15/10/04 at 02:46 PM |
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Hi Fred! Welcome to the madhouse. It sounds like you are well on your way. You certainly have a lot more equipment, space and prior knowledge than
myself.
I think I speak for all here when I say that it would seem like you are a quality addition to the group.
Steve
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
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liam.mccaffrey
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| posted on 15/10/04 at 03:25 PM |
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here here,
i think its about time to put my money where my mouth is, expect pics and progress report on my build in the next month or 2.
wlecome fred
mid engine forever
Build Blog
Build Photo Album
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Alan B
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| posted on 15/10/04 at 04:10 PM |
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quote:
Originally posted by liam.mccaffrey
.....mid engine forever
As in takes forever...LOL
But, yeah I agree...
Middys rule..
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kb58
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| posted on 15/10/04 at 04:54 PM |
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Since your car is going to be very similar to a real Lola T70 Spyder, have you checked to see what a *real* T70 shell would cost? It won't be
cheap but could save you literally years of slow messy work. Unless of course you want to do the whole thing 
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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cymtriks
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| posted on 15/10/04 at 10:31 PM |
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Welcome!
Welcome aboard!
It sounds as if you are starting something very interesting. We'll keep watching.
Just a thought. A spaceframe is only the best choice if you can triangulate it properly. Most kit car spaceframes are actually less stiff than ladder
frames of the same weight for this reason.
For a bigger and more powerfull engine adequately triangulating the engine bay becomes harder. For a bigger car this becomes more of an issue.
A small car can get away with a simply braced structure as the car won't need much stiffness and the hole made by the engine isn't that
big anyway. Having said that I'd always add the bracing.
For a big V engine a ladder frame at the rear may be lighter and stiffer than a spaceframe. It will also give better engine access and will make the
routing of exhaust pipes easier.
If you want some good "big engine" spaceframe tips see the UltimaV12.ca site. This site shows a real Ultima chassis massively uprated by
someone who obviously knows what they are doing.
Also check out the La Bala, Meerkat and Project LMP sites.
Good luck with your project.
Chris.
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Hugh Jarce
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| posted on 16/10/04 at 04:59 AM |
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Welcome Fred. It sounds as if you have a handle on the whole thing, but if you run into any dramas en route you can certainly rely on this
group for support.
Keep us posted.
The pay isn't very good , but the work's hard.
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malakiblunt
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| posted on 17/10/04 at 10:19 AM |
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hi Fred
sounds like your doing great.
know exatly what you mean about the inter conectedness of the design, if you dont have the uprights you cant do the suspension geometry so you cant do
the chassis pick ups...ect..
ARSE ive forgoten the steering rack...now were doea that fit? and wait a minuite if i dont know were they stering arm on the upright is.....
Its all good fun! and this MUST be why we choose to do these things!
on the website thing recently got mine up,once you get the intcial set up out of the way the updateing bit doesnt take long and 10-20m at the end of
a project day can help get things straight in your mind about how the projects going etc, theres nothing like explaining what your doing to some one
eles, to make you see were youve gone wrong!!
Kimini has a good point about the bodywork, as you realy wont beleive just how much work ther is in molding your own, i make plugs and molds for a
living and im Still surprised how long it can take!.
anyways best of luck,
philip
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Fred W B
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| posted on 18/10/04 at 12:01 PM |
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HI All
Thanks for warm welcome and constructive comments. Will post some photo's soon, once I scan the 35mm images I have.
Tim F - Thanks for tip on Gilo Eng, I phoned them but they don't do a Rover/Audi plate. No problem, I want to use a large adaptor plate to brace
my rear bulkhead behind the engine anyway.
Kimini and Philip - I did look into importing a shell (Crossle quoted 1850 UK Pounds for a C9S panel set, while the lovely GD Sportscars T70 Rep panel
set is listed at 2995 UKP on their site) but by the time you pay for the parts, crating, transport and the 30 percent SA import duty in our weak rand
(currently 11.5 to 1 UKP) I can pay less to have a mould made professionally here (and can we make moulds here? - see comment below). Also having a
mould is a big benefit if I need repair panels or want to make more cars. I hope that by making a lot of ribs from a good Solidworks model (I can use
a large CNC router for free, and can get ex packing crate plywood cheap) that making the plug will not be too big a deal.
Cymtriks - I do plan to do some analysis, using the tools and brains we have at work, we do FEA all the time.
By the way, do you guys know that the Superperfomance Cobra's and Coupe's (I see Coupe's advertised in "Classic and
Sportscar" at 73 000 UKP) and the Noble (until recently) are all made here in Port Elizabeth. I have spoken with the MD of the company that
builds them, but he won't sell parts to the local SA market.
Cheers
Fred
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Alez
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| posted on 18/10/04 at 12:27 PM |
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quote:
Originally posted by kb58
Since your car is going to be very similar to a real Lola T70 Spyder, have you checked to see what a *real* T70 shell would cost? It won't be
cheap but could save you literally years of slow messy work. Unless of course you want to do the whole thing
Nice kit by Gardner Douglas here:
http://www.gdcars.com/gdt70/gdt70_index.htm
Fantastic looking car in my opinion.
Cheers,
Alex
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malakiblunt
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| posted on 18/10/04 at 09:52 PM |
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Hi Fred
fair point about importing a body, and yes makeing a plug is not a problem just alot of work! when you say making ribs i asume you mean to make up a
'egg box' former like they do for panel beating, then filling in the gaps? whilst in theroy this should work be warned, its very dificult
to not have the ribs show through,if your useing say clay or similar to fill in. and if you use something harder like plaster and try to sand down to
shape its again very hard to not sand down you ribs as well,and not to get low spots because of the different hardness of the materials.
so i would personaly recomend useing negative formers and stations marked on a base board to cheak profile.and of corse if you want good results out
of the mold the plug has to be beter than perfect! as the resultant panels can at best only be as good as your plug(at best!)
you certainly sound like you have the skill levels to do it,its not technicaly dificult ,but it is going to be MUCH more work than you think!
and if you can make the plug then you can also make the molds,they wont take anyware nere as long as the plug! and you could recycle all those plywood
formers as mold reinforcements!
good luck and i lookforward to watching your progress!
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sgraber
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| posted on 18/10/04 at 10:06 PM |
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quote:
Originally posted by malakiblunt
... whilst in theroy this should work be warned, its very dificult to not have the ribs show through,if your useing say clay or similar to fill in.
and if you use something harder like plaster and try to sand down to shape its again very hard to not sand down you ribs as well,and not to get low
spots because of the different hardness of the materials.... ... but it is going to be MUCH more work than you think!
The process is tedious. It takes a long time. But the rewards are large in the form of satisfaction for a job that not many attempt. You might even
take some liberties with the shape and make something uniquely your own. (just a thought)
My suggestion for your formers is to have them cut approx 4mm inward from your final shape. That way you are certain to have ~4mm of surfacing
material where it bridges across the ribs. These areas are prone to surface cracking if the material gets too close to the ribs. That's just my
.0004 pence since I have already been down this road.
You may have visited my site, maybe not, but I used recycled wood for the ribs and construction sheets of styrofoam insulation cut with a home-brew
hotwire. The entire car is now covered with a thick layer of drywall joint compound (gypsum filler) and in the sanding/shaping phase. I have had lots
of problems with cracking early on, but mostly resolved now that I am going thicker with the plaster surface.
Steve
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
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Fred W B
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| posted on 19/10/04 at 05:56 AM |
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Me again
Thanks for food for thought - I like what this guy says, can remember where I got it from
Lifted from web:
Take the time at a library, and read up on yacht design, and one-off build methods.
What you are undertaking is a direct parallel. Lofting the shapes and then building. The marine industry has been at the 'budget' end of
this for hundreds of years, and the technology crosses over with great results.
The quickest way to get the plug built is as follows:-
Make your lateral section shapes from thin ply or mdf, and do the longitudinal sections the same way. Then set them up in position as accurately as
possible. Next, fill the gaps(where the surface will be) with polyurethane foam. I use sheet cut to fit. The foam is easily and quickly sanded to
shape(but very messy). You can give it a light spray with a cellulose paint to see the shapes easier, when you get the shape near what you want. Use
mix up foam to add bulk if needed, at this point.
The next step is to cover the whole thing with a layer of 600 gm/square meter csm (about 3oz, I think?) and resin, to give a solid base. Sand this
layer to fair it, then coat with polyester auto body filler, and sand again, finishing with 180-240.
Now spray with Durabild (Duratec in USA?). Sand this surface, finishing with 1000 wet&dry, then cut and polish. Six coats of Maguires wax, and you
are ready for moulds. ( I used to use two pack acrylic or polyester paint, but the Durabild is primer and top coat in one hit, and gives a hard,
polishable and mouldable finish in one hit.)
Changes can be made by cutting and adding/removing foam, and locally refinishing as I described above.
This method has been used by myself, to build everthing from small parts, to major sections of superyachts, and a number of wheeled vehicles which
some may be familiar with.
Good luck and quick building!!
Cheers,
Syd.
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