Here are a couple of benches backs that I cut out of 3/16 steel for the local Chamber of Commerce. They turned out really good. Just wish the person in charge of everything else would have had a better game plan. Their attention to detail is definitely not there.
The seats are granite. As far as I know the seats are just sitting on the frame. Lady I made them for said the seats weighed like 400lbs so they shouldn't move. (according to her) She welded the backs to the metal frame. They need to be reinforced but I couldn't convince her to do it. I would have done it a different way but I did what was asked of me.