Metallurgy

[Ken_Potts]

I wonder if 304 Stainless Steel is appropriate for marine use. It would be nice not to have to pay the normal markup for having the word "marine" in the name of the hinges I need for my boat. I'm looking for 8 total hinges for the lockers and I'd like to not have to pay a thousand dollars apiece for them:

http://www.leevalley.com/hardware/page.aspx?c=2&p=52474&cat=3,41241,41261&ap=1

Are there any amateur or professional metallurgists here who would like to comment on the suitability or complete inadequacy of 304 stainless for marine use?

[PAR]

304 is commonly used in the marine environment, though 316 is preferred for a salt rich puddle. You should check the pin, many have mild steel pins with the "decorative" stainless hardware. Take a magnet along with you, if it sticks to the hinge (anywhere) then pass on the hinges, because they'll rust up is short order.

[Guest Oyster]

Send them an e-mail commenting on your concerns. Then analize the response, accordingly. Tell them you are an offshore salt water seadog. If you get some studdering, or questions in return, then keep checking. By the way, how many?

[Barry Pyeatt]

There is a fountain of knowledge in this link plus some somewhat reasonably priced items that you may want. Some are truly pricy but will last. Most will do the job and hold up for quite a while. I've used a lot of the products that they sell and never had an issue with them. Other than some are a lot more expensive than I would like. :cry:

http://www.bosunsupplies.com/StainlessInfo2.cfm

[Guest Oyster]

Thats a nice link and something that I would think that could be usefull for everyone when considering stainless products for the salt enviroment. A shine does not always mean a lasting shine in metals.

[Ken_Potts]

PAR makes a good point about the pin. I'm leaning towards spending the extra money for "marine" stuff since Barry's link (I've bookmarked it) pointed me to some 316 SS hinges that will lay flush to the seat hatches and only cost twice as much as the 304 SS hinges.

Oyster, that's 8 hinges (4 hatches). one of the few places I'm varying from the CS17 design is to add hatches to the sealed air tanks under the seats. I expect to sail in good weather mostly and I figure I can always duct-tape hatches shut if I want a better seal. Or if I really regret not having the airtight tanks I can always glass the hatches over and pretend I built the tanks originally. I'll post pictures soon... I promise.

Thanks for the opinions (and resources) guys!

[Barry Pyeatt]

Good information on their site and good products. And best of all, they take the space and try to offer good helpful information on a variety of topics that relate to marine use and enjoyment/maintenace issues.

Good background and reference for every builder, as Oyster stated, that is dealing with saltwater or marine exposure. There is a difference in SS products and as PAR stated, they aint the same. And they do take shortcuts where they can with some products. I do offer this though, the pins are replaceable on they lesser quality hinges in many cases. So a few years down the road you can knock them out and put new pins in. But the Stainless plates may still be in decent condition to keep using.

Your freebee tip from the "Frugal" maintenance person. :roll:

[Pipefitter]

Another caution of "cheaper" stainless hardware. In some cases,if they used carbon steel machining tools on them at the factory,some filings/residue can become embedded in the surface which will also surface rust. I have found this to be in bow rails and even some high dollar mechanical outriggers and flush mounted rod holders.