Why is it?

[glastornjet73]

That most all of the OG rc10 racer from back in the day hated the graphite cars? Said they were too stiff but then did everything in there power to stiffen the alum tub cars? I dont understand? I know a guy that ran for associated in the day and he would never use a graphite car he hated them and still does but then he proceded to twll me how he added strength and braces in diffrent places on the pans and had the pans hard annoed to make them stronger and then would only run them a month or soo and sell them because they got too flexable? Can someone shed some light on this for me?

[myfordcnc]

I've wondered about carbon chassis too. But I have no practical racing experience. I remember some members here saying just that they were to stiff. Perhaps there is a sweet spot between the carbon chassis and the perhaps the too flexible alum tubs that necessitated a bit of bracing. ?

[harvey]

I think the answer lies in the properties of the two materials. Carbon is snappy; if you flex it, you'll get a lot of the energy back, in a hurry. Aluminum can have a damping effect, with a less energetic return of energy. This helps the chassis by providing a predictably compliant handling characteristic.
As an analogy, I have a snowboard with a lot of carbon in it, which makes it light and snappy. If I load it in a turn (flexing it), it will have a tendency to launch me into the air when it returns to it's original shape. Fun! Great on fresh groomers.
A different board has a thin sheet of aluminum throughout. This board handles choppy conditions really well i.e. you don't notice the rough surface of the snow as much, so it's easier to hold a consistent arc. Smooth! Predictable on skied out slopes.
Hope this helps?

[Bottom Feeder]

... and had the pans hard annoed to make them stronger and then would only run them a month or soo and sell them because they got too flexable?

Anodizing aluminum is only for wear resistance and looks. It does nothing for the strength or flexibility of the aluminum.

I think the answer lies in the properties of the two materials. Carbon is snappy; if you flex it, you'll get a lot of the energy back, in a hurry. Aluminum can have a damping effect, with a less energetic return of energy. This helps the chassis by providing a predictably compliant handling characteristic.

Entirely this. On paper, there should be zero flex in the chassis and suspension with 100% of bump absorption done with the shocks and springs. But in the real world there is lots to be said for a bit of bulit-in flex giving the car 'feel'. Same can be said for full-size race cars, and Grand Prix motorcycles are an even better example. The stiffer the frame gets, the worse they handle. Those guys have been playing with engineered-in flex for decades now.

[Y'ernat Al]

http://www.rc10talk.com/viewtopic.php?f=35&t=12733

[fredswain]

I personally preferred graphite chassis over the tub. Keep in mind I sucked with both!