Boat-Work Season

It’s still a bit cold to begin sailing in Montana, but ski season is officially over so let boat-work season begin! Thankfully most of my projects this year will be easy, I want to re-finish pretty much everything and make a few mods/improvements, but nothing too drastic. One of my projects for this year will be to construct a new rudder gantry. I must say that the original gantry that I fabricated out of solid oak was probably the strongest thing on the entire boat. After two years of useit never had a single failure, but that’s probably because it weighs a ton. Going to a carbon gantry will save me a lot of weight. So now I’m trying to figure out what diameter and wall thickness I need in a carbon tube to give me good weight savings but still be reliable. Is there a standard recommended size for gantry tubes?