its the carictoristics of the metals as to why alloy cracks (same reason why stanless mainifolds crack with the thermal dymamics of heat )

alloy is light and strong but doesnt like heavy(hard) stress loads at one point

One question what about modern sports bike frames, all alloy (aluminium) and quite often the swing arm pivot point is cast alloy and the swingarm is also alu alloy. Now modern sportbikes put out major power and there would be considerable force running through the rear swingarm on a sportsbike.

My 0.02 c

Cheers

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225hp atw on 14psi. 1/4 Mile no idea. Take one 1971 Mini Clubman, one Starlet GT Halfcut, Simmer over a warm MIG Welder, and Voila Minstar! www.mpdesign.id.au

that's true!

I forgot that my previous engineer did actually tell me I could make my radius arms out of 50x5mm 6005A alloy... they were gonna take the rear load.... I was just regurgitating what Tricky said

Mafia, talk to a structural engineer type person for some advice

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did I tell you that I won a trophy?

True Matt,

Different alloys display different porperties and characteristics I guess.

This information I gained was from a guy who worked for metal merchant (Onesteel) that wholesaled alloy and steel and was considered very knowledgeable! - he was their resident structural engineer!

Personally, I dont have a problem with alloy. Look at yacht masts and spars - hollow extruded sections under enormous loads!

Cheers,
Tricky

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"Not Speeding Officer..........Qualifying"

Ummm....yeah....but they break....

Yep sure do.

That's one of the examples the guy used.

Hence why now all racing yachts use composites like carbon etc.

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"Not Speeding Officer..........Qualifying"

and they break to and cost crap loads more

Jon

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Roundies and Clubbies(except vans) are both ugly that is why I have Midas and a van
1293 Mini Midas Bronze,1275 Clubman van

But they''re a lot lighter! Just depends on how often you want to (can afford to) replace them!!

Could have a full composite Sub-frame, would have to be well designed and probably still would take a few go's!!

I believe in fit for purpose. You can make anything from anything...... i.e. carbon fibre wheels - was done at the 2004 Formula SAE event... and looked very cool.. not to mention they only weighed about 600 grams per wheel... now theres a way to overcome inertial resistance!! And of course the teams in that competition that are making full composite chassis - most of them take a long time and afew go's to get it right though. Or in Monah's case of '04, the chassis delammed on the day of comp.!!

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Answer the Question....
BUT always Question the Answer

That would be a bugger.

Like the norm in F1 now is to have an aluminium firewall behind the driver which cradles the powerplant unit, and the rest is basically made out of composites.

The drivers tub (safety cell), and all the bodywork, suspension components and even brakes rotors are all carbon.

Hellishly expensive but incredibly light and strong (at least in tension).

We could do a carbon fibre subframe, but it would have to be done out or pre-pregs - who can afford that and the freezer to store them?

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"Not Speeding Officer..........Qualifying"

Not the most knowledgeable when it comes to carbon creations.... why pre-pregs?Only experience i've had is watch someone make wings... reaonably sure that was pre-preg... Would be nice to do actually...
Is that pre-preg goes off in normal atmospheric conds and any method other than pre-preg needs to be baked?

I was lookin at makin a dash from carbon.... but got over it and bought a wood grain one instead for a rediculous price...

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Answer the Question....
BUT always Question the Answer

Pre-pregs come from the factory already resin-bound.

They have an outer layer of plastic on either side which you peel of then you basically lay the pre-preg to the job and vacuum bag.

They are the ducks nuts because the resin to cloth ratio is perfect, as is the resin distribution within the cloth.

You need a freezer o store them thoughas they start to cure at anything above about 1 degree C.

You only need to bake to speed up the cure time, but I have heard that some resins bond better when they are baked, as the added heat helps the chemical reaction become more complete.

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"Not Speeding Officer..........Qualifying"

The only bit of carbon the Morris will be wearing is a pair of pre-preg carbon bullet mirror shells I made years ago at a composites course. They were autoclaved in a spun brass shell and ring like steel when you tap them. Overkill I know, but I have to use them on something, they have been floating around for ages!

Madmorrie

Least they might hold up if someone nails one when your car is parked!!

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Answer the Question....
BUT always Question the Answer

I pity the other car!

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"Not Speeding Officer..........Qualifying"

Anyway

Quick question, should I cut the bottom panel off? (Below boot) I’m TOLD that it creates drag.

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