aluminium chassi

[Bryce]

I love using aluminum.... take a look at my build thread.

I think aluminum has its place.

Aluminum can be stronger than mild steel, however it is more flexible. So it depends on what loads the frame will see and what deflections you are confortable with. Aluminum is 1/3 the weight and 1/3 the stiffness of mild steel. If aluminum was used to replace steel with the same exact design just thicker than it would end up weighing the same to maintain the same stiffness. however you can change the design to take advantages of the properties of aluminum.

Heat treat is a must if you plan on welding to the aluminum.

As stated before, aluminum will work harden and eventually fatigue. If your fatigue loads are 10% of your utlimate strength than you probably will get good life from the part.