Polysulfides and stainless bad? Huh?

[chris95040]

A guy at the boatyard the other day was telling me, as I gooped polysulfide all over some stainless hardware I was bedding down to wood, that he thought polysulfide could corrode stainless. I've *always* used the stuff in this scenario, but it got me googling and I turned up this from the Wikipedia article on Polysulfide:

Polysulfides, as sulfides, can induce stress corrosion cracking in carbon steel and stainless steel.

????? Can anyone describe this interaction for me? I even scuff the mating surfaces up a bit before bedding, probably removing the passivated layer in the process, I wonder if that could make this corrosion even more likely?

The poly sulfide products themselves claim compatibility with stainless, so I have to believe that statement on Wikipedia is taken deeply out of context.

[roverhi]

News to me. Have been using Life Caulk going on 40 years without an issue with Stainless. Don't think I'll quit now.

[xymotic]

News to me too but just one more plus for butyl I guess

[delmarrey]

You can't believe everything that Wikipedia has to say.

Maybe if it trapped saltwater under the surface it could be a problem, like around stanchions. But the polysulfide itself is unlikely. I have a 35 YO boat and the SS plating on deck is just fine. The sealant has been replaced a time or two w/o any affects to the SS.

[hellosailor]

You could flag that as needing confirmation, on the Wiki. And call Boatlife on Tuesday to ask them if they've heard of this.

There are griefers who try to sabotage Wiki pages, as well as plain old mistakes.

[chris95040]

Just to settle anyone's nerves, the reply from Boatlife:

Thank you for your inquiry.

I have never heard of polysulfde inducing stress cracking in stainless steel. Life Calk has been used for decades in the application you describe with no ill effects.

Hope this helps.