OK, so what you're really asking for is for others to validate and agree with your opinions -- you could have saved a lot of time if you had just labeled your thread that way to start with.
BTW -- my guess is that your "304" ladder either wasn't 304 or that it had other issues going on inside it.
Oh I'm sorry, I thought this thread was because someone asked for advice on the use of 304 versus 316 in a marine environment, I must be right off topic.
I was just offering a little bit of advice on that specific subject, based on 21 years of real world experience messing with old boats and fabricating stainless.
My opinions are based mostly on the 304 failures that I have personally witnessed - that does not mean that 304 will always fail but I have seen it fail too often to accept it when there is a better option available in 316.
If there is credible evidence to dispute my humble opinion, I would like to hear it.
Baggging the author is not what I would call credible evidence, that is just argementative tactic. This is supposed to be a discussion not an argument...
I am currently working on an 9 year old Hunter 380 which has the same rust problem with its boarding ladder - I suspect 304 because it holds a strong magnet and because is very rusty and because it is an American built production boat.
Compare that to the 30 year old main boarding ladder on my boat which is I believe 316. The indicators for that, are: no rust, will not hold a magnet (except on the welds) and is is a New Zealand built custom.