[JesseK]

We CAD the entire robot, but we shell rather than extrude the box aluminum (etc). We've never used weldments, but I wouldn't mind learning what they're useful for. I'd particularly love to know if there's a way to predict the tendency for a frame to warp in a certain direction if a weld is placed on one corner vs. another.

I generally spend a few hours taking CAD models and making dimensioned drawings for the assembly. It's pretty straightforward: 1. Conjoined edges are welded at the welder's discretion (he knows more about strong welds than I do) and 2. Don't weld over holes.