C4.1 Chassis

[JustARcFan]

The master has spoken

Originally Posted by elvo

Fabs is 100 million percent correct. Technically.

HOWEVER.

There is one little twist in this story. People tend to buy expensive little cars and plow them into solid objects at high speed, I think that is a fair thing to conclude from this thread. So manufacturers are forced to design chassis to cope with that. That is where material strength does influence stiffness, through dimensions.
Example: if the C4.1 chassis were made out of 6061-T6, it would need to be 4mm thick in order to be strong enough. If it had been 7075-T6 - which is very strong - 3mm would have sufficed.
Both materials behave exactly the same in the elastic part of the deformation curve, but the strongest one allows lighter construction, and thus, more flex. A thinner chassis flexes more.

Stronger alloy = more flex. Counterintuitive, eh?


Very similar story: http://www.willswing.com/Support/FAQItem.asp?reqFAQ=66

[Chrislong]

Soooo Elvo, whats your opinion regarding C4.1 to conclude...

[elvo]

Originally Posted by Chrislong

Soooo Elvo, whats your opinion regarding C4.1 to conclude...

I think it looks and drives a lot like the S2, which was my baby....

[Battle_axe]

spot on there elvo glad to see that there is some people on here who understand materials too fabs great explanation there

so all in all guys the problem isnt the grade/type of ally its the thickness that it is. although if you make it thicker the chasiss will be less "bendy" so will handle differently.

i think in this day and age there is allot to be said about differing layups of Carbon and fiberglass to achive the elastic nature of the matiral required

[smokes]

Originally Posted by elvo

Fabs is 100 million percent correct. Technically.

HOWEVER.

There is one little twist in this story. People tend to buy expensive little cars and plow them into solid objects at high speed, I think that is a fair thing to conclude from this thread. So manufacturers are forced to design chassis to cope with that. That is where material strength does influence stiffness, through dimensions.
Example: if the C4.1 chassis were made out of 6061-T6, it would need to be 4mm thick in order to be strong enough. If it had been 7075-T6 - which is very strong - 3mm would have sufficed.
Both materials behave exactly the same in the elastic part of the deformation curve, but the strongest one allows lighter construction, and thus, more flex. A thinner chassis flexes more.

Stronger alloy = more flex. Counterintuitive, eh?


Very similar story: http://www.willswing.com/Support/FAQItem.asp?reqFAQ=66

Fabs is right; But it is not just about the materials it is the shape of the part and how it loaded.

http://en.wikipedia.org/wiki/Buckling
http://en.wikipedia.org/wiki/Bending
http://en.wikipedia.org/wiki/Second_moment_of_area
http://www.mdme.info/MEMmods/MEM3000...ea_Moment.html

you need to understand simple elastic bending theory

http://www.roymech.co.uk/Useful_Tabl...am_theory.html

Only bad thing is when you plastically deform the part and bend it back. Is that the material will have lost its elastic properties and bending the part will reduce it fatigue life.

http://en.wikipedia.org/wiki/Deforma...ic_deformation

[elvo]

Indeed. Composites are a big can of worms....

[smokes]

Which composites. Concrete and steel? Metal alloys hastelloy inconel duplex. Fibreglass or carbon fibre/direction layups or non- directional.

[Body Paint]

Originally Posted by elvo

I think it looks and drives a lot like the S2, which was my baby....

How can you call it your baby... I was there at the time of conception you know LOL

[Pops]

Originally Posted by Body Paint

How can you call it your baby... I was there at the time of conception you know LOL

ooh err...Now we know why it sticks to the track so well..dirty boy

[tony12795]

I always thought it was Craigs baby, althought Elvo was there at the birth.

DNA Test me thinks

Does that mean Jonathans the mother.... which is wrong in everyway

[Fabs]

My point was solely aimed at clearing the fact that changing the grade of aluminium has no effect on the chassis stiffness. I did not mention changing the shape, and by all accounts, under what is considered as normal use, the material is supposed to keep to the elastic range of the stress scale.

If it goes into plastic deformation, and gets bent in a permanent manner, then bent back into shape, so long as the bending wasn't excessive (where it went out of plastic deformation and into the striction domain), then it will by all effects keep the same elastic properties. BUT it's likely the chassis will be slightly longer (maybe not enough to even measure it though) and if it happens too often and always at the same place (which is unlikely), it could effectively become more and more fragile and end up breaking even during normal use.

To clear things up, I haven't got a clue what the mechanical properties of the C4.1 chassis material are. I am not here to comment on whether it bends because of the choice of alloy or because of the design.

[Timee80]

How many everyday drivers have found the chassis bending to be a problem?

[Pedros20]

Well.... Pat's bent his tonight at Don Valley. There's one Tim.

[Richard Lowe]

Originally Posted by Body Paint

How can you call it your baby... I was there at the time of conception you know LOL

And who gave you lots of ideas at that Oswestry national...?

[buhade]

Mine worked good with std chassis at hrotovice Mibosport Cup. Finished 2nd in 3rd a-main after cool fight with hupo. Now I am going to test the Carbon R chassis.

[racingdwarf]

Problem is simple...build a car to win in the hands of great drivers,you can forsake a little strength for better handeling and win national meetings. BUT release the same car to us the genral club racing hard core and your in for problems as there can be some bash and crash...on some less than world std tracks. I think tbh the car for sale in the shops should have a thicker/stronger chassis, yes it may not handle quite as well but in all honesty most club/national drivers wouldn't notice that little change,And this thred would never have existed.
Then I would have sold the TEAM chassis as an upgrade stating the fact that it has more flex, but not as strong.

CML could then have made more money, as every one would rush off,buy the new chassis, bend it, realise they are not Neil cragg and put the old one back on.

But the big problem could be is the car only better because of the flex? but just not strong enough for club racing Hmmm

Just a thought

[carpenterdean]

Originally Posted by carpenterdean

What about now?

Not had any issues since i put these on the car and i can't notice any difference in the handling, however i'm not exactly good so someone more experience may be able to notice the difference.
Like the carbon one by rudebits but £120 ouch!!!! before i start getting bollocked i know c/f is expensive and they obviously have setup costs so it's probably a fair price i'll just have to put a few shekles aside.

[TommyG]

Can anyone who's bought or tried the rudebits carbon chassis comment on any noticeable differences?

[Pops]

Originally Posted by TommyG

Can anyone who's bought or tried the rudebits carbon chassis comment on any noticeable differences?

Same question from me

[buhade]

Its on the way to me, maybe it is ready for the EOS in Hrotovice!