[lordjw]

Greetings to everyone

Real racing world uses lightweight materials such as carbon fibre and kevlar extensively. For some reason I was unable to find any references that would indicate use of these materials in slotcar world. Since I like to discover always something new I decided to have a go and build myself carbon fibre slotcar chassis.

Study of materials revealed that carbon fibre is very hard and lightweight, but will be shattered on hard impact. Carbon needs to be laminated with more flexible material for maximum durability. Kevlar or glass fibre can be used to protect carbon fibre. I chose glass fibre for its price and processability. I had also some kevlar, but it's very hard to cut kevlar - you should have very sharp ceramic scissors for this purpose.

When constructing composite chassis you should have at least three layers of material in order to achieve hard, inflexible piece. As bottom layer I used 195g/m2 carbon fibre, middle layer of a body is 200g/m2 glass fibre. Third layer is lightened Revell EasyKit plastic body. Carbon- and glassfibre were first laminated to produce very thin 0,7mm sheet. This sheet was glued with epoxy to modified EasyKit plastic chassis.

Ball bearings were installed to rear. Standard Scalextric gearing components were used. Motor is from electronics surplus store. Guide is the best available, NINCO spring loaded guide. Tyres are from Revell kit.

Finished AudiTT with ball bearings and carbon fibre chassis. Carbon fibre is clearly visible, it looks cool and gives the car more street credibility.

Now I don't mean to boast, but this car is really the best slotcar I've ever driven. Carbon chassis and ball bearings really make the difference. With very thin composite chassis you are able to achieve very low center of gravity. Ball bearings eliminate any free play on rear axle. The result being very quiet car with extremely good handling. And this was just a test project where body weight was not optimized at all, motor is low RPM low cost, tyres are thin EasyKit ones and gearing is just standard Scalextric. Real racers could do wonders by upgrading these components.

How much did it cost then? You will be surpriced!

Ball bearings 2 x 2 = 4 euros (£2.68) - From electronics surplus store
Revell Easykit 14 euros (£9.38)
NC2 type motor 2,5 euros (£1.68) - From car cassette deck mechanism
Sheet of carbon fibre 60mm x 130mm 0,4 euros (£0.27)
Sheet of glassfibre 60mm x 130mm 0,1 euros (£0.07)
Epoxy resin 1,5 euros (£1) - High quality epoxy
Scalextric gearing 3 euros (£2.01)
NINCO guide 1,5 euros (£1)

Total of just 27 euros (£18)

More pictures of this project can be found at:

http://koti.mbnet.fi/scalenet/

Text is unfortunately in Finnish, but there's lots of pictures.

I'd like to know if somebody else has experimented with carbon fibre?

Julius

 

[Russell Sheldon]

Very nice work, Julius.

Pink Kar announced a Reynard LMP275 with a carbon-fibre body at the 2003 Nurnberg Toy Fair, but it has yet to be released.

Image courtesy of MRE.

Although not as lightweight as polycarbonate (Lexan), it is probably a lot more durable.

For anyone wishing to make a carbonfibre chassis, Cartrix sells pieces of carbonfibre measuring 1mm x 62mm x 130 mm, while Pro Track make carbonfibre axles.

Here's a simple carbonfibre chassis, expertly made by Mark Gussin:-

Kind regards

Russell

 

[Doug]

That looks great Julius. Perhaps we can put it in the resources section?

Now you just have to send it here so we can verify the weight saving and speed

Good work

 

[lordjw]

Thanks for positive comments

Is there really interest for this kind of how-to articles? If you really want FULL story of building carbon Audi to "resources" section , please tell me how it's done. Contains 17 pictures about 25K each.

Julius

PS.
If there's any interest I could provide other articles as well. I'm writing these for our finnish site so it's just a matter of translation for me. My specialities are airbrush painting, electronics and composite materials.

[email protected]

 

[EDDY - Junior Junior racer]

do u save much wieght

 

[lordjw]

Hi!

I do save some weight but we're talking about just a few grams. Biggest benefit is lowered center of gravity. Lead weights can easily be placed 1.5mm nearer to track surface. This doesn't sound much but in real world Honda engineers lowered NSX engine just 15mm and it improved the performance of the car significantly. Also installation of ball bearings has more importance to car performance than just plain weight reduction.

Julius

 

[peter]

Great job,

Personally I think it would be fantastic to have some of your articles in english, especially the step by step ones. It is always a nice learning exercise to see how others are doing stuff related to the slot hobby.

//peter

 

[howmet tx]

Hear hear! Lots more of this please!

Your carbon fibre project has me intrigued. I'd love to hear more, and step-by step instructions would be great.
I'd be sad to swap the warmth of my soldering iron for the teeth grating slicing of carbon fibre and epoxied fingers, though!

 

[LSIntegra94]

What are you using to cut the carbon fibre? And where in the world are you getting it for such a low price!?!?!? The stuff from Cartrix is £7 a sheet if you can find it.

 

[Intergrali]

pendle have the cartrix carbon sheets

 

[Russell Sheldon]

I'd also love to read your article in English, Julius!

For anyone not wanting to cut or drill carbon fibre, you could components made for Plafit chassis by Igoya Works:-

Mark Gussin's article on how he built his chassis is a worthwhile read, also.

Kind regards,

Russell

 

[lordjw]

Hi!

Where to get carbon fibre? You should find a composites shop that is willing to deliver smaller amounts of fabric to racing and boating enthusiasts. Unfortunately you propably are forced to buy minimum amount of one square meter of the fabric.

What will it cost?
Fabrics used in Audi:
Carbon fibre 195g/m2 fabric = 32euros(£21.44)/m2
Fiberglass 200g/m2 very fine transparent fabric = 7euros(£4.69)

So you are forced to buy 1m2 but your car chassis plate will consume only:
0.06m x 0.13m = 0.0078m2 Let's round this up to 0.01 to allow some tooling.
Price for chassis materials is about:
0.01 x 32euros = 0.32euros(£0.21) for carbon fibre
0.01 x 7 euros = 0.07euros(£0.05) for glassiber
Just checked the prices from composites shop.
You will need high quality epoxy as well. This costs 57euros/2l (£38.19)
It takes about 30-50grams to laminate chassis depending on how precise you are.
If you want to use kevlar: 170g/m2 is 30euros/m2 (£20)

How to cut it?
When you have laminated a carbon fibre piece you should wait until resin is almost hardened. Almost is the key word here becouse you have short time slot where the resin has dried, but not fully hardened. You can easily cut the 0.7mm composite plate with scissors or hobby knife. Make the tooling and leave the chassis piece to even surface and let it harden fully. If the resin dries and hardens fully you can still model the piece with hobby saw or knife. There is really no problems cutting carbon but avoid kevlar, it's very difficult to cut with anything.

Will be posting that article soon, hope it's useful

Julius

 

[howmet tx]

Excellent. Thanks Julius.

 

[lordjw]

Hi!

Russel, thanks for interesting link to Mark Gussins article. He used more professional components with his chassis than I did with mine.

Best Regards

Julius

 

[lordjw]

PS.

Sorry Russell, spelled your name wrong. I shouldn't post these replies during these late hours.

Julius

 

[MK2-Escort]

I brought one of those TT's today. I started making it into slot car about 4hrs ago, and it still isn't finished

Infact it's a complete bodge job! I tried at first to make it inline, but it all went wrong with the dremmel- and now I've hacked up a beetle chassis and tried to do a cut n shut.. I bet it will be complete [email protected] when its finished!

 

[GRAH1]

mk2 I have done a how to article on this conversion Its on the forum entitled what to do with those revel kits you got at xmas its also on my web site

 

[MK2-Escort]

Found it, Graham - here.

I gave up at about half 12 last night (surprised how fast the time went!) Anyway, my revell chassis is all cut into pieces, so that is useless now. I saw your article at the bottom of that page about building your own chassis, which looks very useful. I think I might give that a go

Cheers

Sam.

 

[Doug]

A full 'how to' has been added to the resources section here.

Thanks Julius

 

[lordjw]

Hi!

Nuro, excellent job, story layout looks good

- thanks!

MK2-Escort, if it's any help - I have also made a step by step story on building Revell EasyKit the easy way - no carbon or ball bearings used. It's in finnish, but it's the pictures that really tell the whole story. Take a look at:

http://koti.mbnet.fi/scalenet/

Click "Autot" (cars)

Go to the bottom of the page and click "Edelliset>>" (previous)

Story can now be seen: Rakenna Revell EasyKit DTM Mersu, click "Lue lisää" (read this)

Really hope you are able to eventually build your kit. Nothing beats the feeling when you're driving car that you have built by yourself.

Julius