Quote Originally Posted by EddyCurrent View Post
I think you will find mild steel is sufficient for the frame and will be much cheaper than aluminium, also the extra weight will be a benefit when the machine is working.
Agree with Eddy and aluminium tends to crack around welds from vibration over time so wouldn't use it for the frame. I weld aluminium often and wouldn't build the frame from it unless weight was critical and even then I'd use much thicker aluminium than I would steel.