Man. Yes.I'm thinking that a 1/2" thick walled bollard would be strong even with 6061, then also increase the thickness of the ring and cross member.
like the stein units... yes.. It's best of the climber is controlling the load for it to be fine tuned as much as possible... What is the mini porty's diameter?That is what I am thinking also. I would like to make the OD of the ring 7" dia., with a 2.5" dia. bollard. When you say 1/4 cleats, do you mean the stays, 4 on each side?