Stainless Steel Yacht ?

[s/v Beth]

Getting into welding and machining has made me realize that there is a whole bunch of materials out there that may be great for construction but may cost a little more. I priced quarter inch steel, Aluminum and Stainless Steel plate- the costs were 150, 350 and 550 for a 4 by 4 plate. Higher but doable.
I went on to Yachtworld and saw- there are a few SS yachts out there. I would think this would be the ultimate material- if it has a high enough Chromium level it would be highly rust resistant, tough and and last forever with very little care. Anyone that has one care to comment?

[motion30]

1/4'' sounds heavy unless its a really big boat I like the idea of stainless but.......here it goes YOU ALL GONNA HERE ABOUT CREVIS CORISSION FROM THE NAY SAYERS From my 32year welding in the petro chemical and power insdrustry I like ss

[motion30]

But the way guess what the inside of a nuclear reactor is made from? you guessed it ss

[Tristan]

I do not think it will last forever. Stainless steel to be "stainless" needs some oxygen access . If it doesn't , it would corrode like regular steel. You would have to protect it somehow under the water line. Effectively you deal with it like with carbon steel except it's weaker and more expensive. Above the water line it might be a good idea , but for the aesthetic reasons you will want to paint it anyway.
T.

[cat man do]

Corten steel hardly rusts and being high tensile, thinner plate thickness can be used

Weathering steel - Wikipedia, the free encyclopedia

[Reefmagnet]

If stainless steel were that great, they'd make ships out of it. It's too heavy, suffers from carbide precipitation in the HAZ of welded joints (i.e. rusts) and with only 50% the thermal conductivity and something like 30% more expansion coefficient of low carbon steel (I could be a little out on those numbers - working from memory), it distorts like crazy when welding sheets of it together unless you really know what you are doing. It also needs to be pickled and polished in order to retain a nice non rust covered surface.

[bangkaboat]

[minaret]

Cor-ten steel with zinc flame spray is my vote, if you must have a metal boat.

[s/v Jedi]

I think Monel or Cupro Nickel will do better and think I've read about boats build out of these metals.

ciao
Nick.

[Mr B]

Stainless Steel work hardens, After a while the constant moving in and out will eventually crack it.
Thats why I went back to carbon steel in my 40 foot steel Catamaran.

I would have liked stainless, the extra cost would have been eliminated by no painting,
But panels cracking in my boat was not an option I liked.

[cat man do]

Originally Posted by Mr B

40 foot steel Catamaran.

Please tell us more

[Weyalan]

Adrian Flanagan did a north-south circumnavigation (of sorts) in a stainless steel yacht. It is detailed in his book "Over the Top". there is plenty of detail about the boat and how it performed.

[Microship]

find Geronimo if you can... was in Port Angeles 8 or so years ago. All SS hull, a beauty.... would love to see her now. 50 foot or so.

[s/v Beth]

This is the one that caught my attention. Seems like it has very few of the problems you attribute to stainless. I do note that she is painted though. I wonder what type of steel it really is.
1981 Auzepy Brenneur Stainlees steel Ketch one off Sail Boat For Sale
Also- what is the price of a Corten steel quarter inch, 4 by 4 plate? I am just using that size for comparison.

[Reefmagnet]

The best application of stainless steel on a boat that I have ever seen simply involved the addition of stainless steel flat and round bar sections to all points on the hull where the paint would be susceptible to rubbing or flaking off. Essentially this meant it was applied around the perimeter of the hull, window and hatch frames and a plate of stainless was placed under each deck fitting. The stainless was welded and fared in such a way that it blended perfectly with the steel.

This thread has got me thinking though and, aside from the additional complexities of welding it together and cost in relation to mild steels (although you could get by with thinner sections relatively speaking), super duplex stainless steels like 3cr12 would possibly make a great boat building material???