pic: Off Season Sheetmetal 6WD

[tim-tim]

As a response as to whether cross supports are needed:

Probably won't need dedicated cross supports for the purpose of cross supports. This may seem confusing; but once you start building off of this frame (i.e superstructure, arm, etc), these new components will act in the same way.

I would say a relatively light (in mass) and strong (against bending) piece across the bottom becomes useful when designing mounting locations for the electrical/pneumatic components.

I think the frame looks well designed, but as always room for improvement. Design is iterative and you can always find ways to lower weight and time for machining. Now that you have something to start from, tweak it to make it better.

Also, you may want to do some research into Finite Element Analysis (FEA). It allows you to determine the stress throughout the design. Precaution: FEA is a difficult skill set to learn. You may want to ask a mentor that is familiar with it to help you. This will really show where the design is poorly designed and overly designed from a structural standpoint.

Keep up the work