Iron Boat Nails and Refastening Methods

[Captain Ted]

I have a fishing dragger with 3" thick oak planks on a sawn frame backbone. Ribs are 4x6".
Boat is from the 1940's and the fasteners are bleeding. She has galvanized iron boat nails in her. We would normally just drive new galvanized boat spikes into the planks and cover them with a bung. When the planks become nail sick we cut the plank off, cut off the old iron spikes flush with the frame and then fit a new plank with new galvanized iron spikes.
Seems to always work well. We never try to pull a fastener, always leave it alone in the rib.
Do you have any other methods we should be exploring?
We never mix metals; always galvanized iron.
What about the galvanized "steel" ring shank spikes you can get for pressure treated wood? Does anyone have any experience with them on oak to oak.
Drop me a note.
Thanks,
Capt. Ted

[Thaddeus J. Van Gilder]

I don't know about galv. steel ring shank nails, but one boat I used to work on used galv. boatnails above the water line and it seemed to work well. This was a 150 foot on deck barquentine, though. They were big spikes.

anyway, old nails on the boat were removed from the frames using a sliding hammer like the ones used to fix car bodies. a #10 or so stud was weld to the end, and the stud was threaded into a hole drilled into the end of the old nail, suitably tapped to accept the stud.
The old nails came right out, and the holes were filled with a suitable plug as per coastie recomendations.

Thad

Thad

[JormaS]

I have a question to both of you. I have a hull with 2" Scots Pine planks on 4 by 4" double frames of Oak. The fastenings are galvanised iron nails. The boat is not very old - built in 1975 - so the fastenings are quite OK so far. However, I have noticed that some bungs in the underwater part have started to creep outwards. I´m going to check them on next haul-out. A similar thing has happened with many bungs on deck, and when I have removed them I´ve found a nail head covered with rust. I have concluded that rust makes the iron expand and thus pushes the bung out. I have scraped the rust off and covered the nail heads liberally with red lead paint, then put in a new bung.

Now, if the bungs in the bottom follow this same pattern I could give those nails the same treatment. The question is, is it worth while? Is it possible to lengthen the nail´s life in this way or is it in vain? Maybe the rust itself gives protection to the iron. Or maybe the head is´nt that important and the condition of the shank is what counts.

What say you?