Thanks for the comments, they are all appreciated.
I put the bare frame (as shown in the photo in my
previous post on the postal scale in the shop...10.5 lbs.
We worked today on figuring out how the ball handling mechanisms will fit, and will probably add an upper frame made of the same steel tubing, which will add about 12 lbs, for a total frame weight of under 24 lbs. This is about the same as last year's plywood robot. I think we're doing OK, since we don't see how we can get much weight in the mechanisms this year. I guess if you have 80 lbs of stuff "on top" then the extra 5(?) lbs that steel adds would be a problem.