Rudder pintail. Stainless or galvanized steel?

[AndCur]

Hi

I have to replace the rudder pintle at the bottom of the skeg as the old one is badly corroded it was galvanized steel. The skeg is galvanized steel covered in GRP. Would you make the pintle out of 316 stainless or steel that is galvanized to keep all the metals the same?

 

[KenMcCulloch]

I think if you use stainless steel the existing galvanised steel will corrode in proximity. Better to use galvanised.

By the way a Pintail is a kind of bird, it's a pintle you are after, sorry I can't help being a pedant.

 

[Poignard]

I'd keep it the same. In a misguided moment I once used a s/s shackle to connect my galvanised steel anchor to the chain and the chain and anchor soon began to rust.

 

[vyv_cox]

I'd keep it the same. In a misguided moment I once used a s/s shackle to connect my galvanised steel anchor to the chain and the chain and anchor soon began to rust.

??? I have used stainless steel shackles and/or swivels with a galvanised anchor and chain for the past 30 years. Even as a summer liveaboard, anchoring hundreds of times per year, the worst that happens is that the zinc is lost from the last three or four links after several years. The combination is not in water enough, or in good electrical contact, for galvanic corrosion to be a problem.

Permanent immersion on a rudder pintle is a different matter though, as would be a stainless steel shackle on a mooring. I wyuld stay with galvanised steel.

Incidentally, when I destructively tested chandlery-bought shackles the stainless steel ones were markedly stronger than the galvanised. Results on my website.