hey ya'll great responses. thanks so much, but I'm not feeling the vibe. I got aluminum suggestions, ss, and wood. They used to call me Mr wood. I can certanlly build almost anything from wood, including my davits, and all thats previously been mentioned, But my question still stands, anyone build or kno someone who has built galv. pipe works on their boat? Sorry, ther was one post i feel gave a previous install a sort of thumbs up in that it was very heavy and pro done to have been hot dipped after the welds,etc. Maybe it was cold galvanised-sprayed on, i dunno. I just feel that if i built it out of pipe it would have much more inhearant strenght. Anyone have or no of a boat with galvanised pipe onboard?
I worked on merchant ships, that had mixtures of steel and galvanised steel. Not much galvanised, but i remember a galvanised gangway we carried, and stored on deck when we were at sea. Their were other parts of the ship, that were galvanised, but they had to be painted, as what happens when at sea, is the salt water acts as an electrolyte, and causes a current between dissimilar metals, and destroys the weakest metal. So if you attach steel to aluminum, the aluminum will corrode, the zinc that is used to galvanise steel, is a sacraficial metal, it works by corroding, so the steel dosent have to corode. Which is why we painted it. It didnt matter with the gangway, becauser the whole thing was galvanised steel, and it wasnt attached to the ship, so you wouldnt get a corrossion point round the point of attachment.
I worked for a South African, while i was in Israel, he owned a 70 foot steel sail boat, he had built himself in south africa, (well he hadnt exactly built it himself, he had a steel construction business, and he got the guys he employed to build it) He was a qualified structural engineer, he built the frameworks for buildings. He had also worked for berger paints, testing out paint systems for steel, and his hobby, was building boats from steel. He told me, that if you build a boat in steel, everything has to be steel, he said, you can use metals like brass, or bronze, but you shouldnt use stainless, or aluminum. he told me, people build steel sail boats, then to make them look a bit posh, put stainless stanchions on them, and stainless davits, and all sorts of other stainless. Within a few years, their are holes all over the deck, where those stancheons and davits are, because he said (this was back in the eighties (their is no paint system, that will permanentally sepperate two dissimmialr metals, and eventually the sea water (electolyte) will cross between the two metals, and corrode them.
I know you were looking for answers for a fiberglass boat, but, what I say is, it wont make any difference if its galvanised powder coated, or painted, not if you are fitting it to a fiberglass boat, but if it comes into contact with stainless steel,or other metals, you will start to see corrossion. If you used brass tubing, or copper, it wouldnt corrode anything.
