Teak boards over steel deck

[ayates]

I have started volunteering on a Brigantine tall ship youth sail training program. Their ship is a steel hull with a steel deck. The deck covered with teak planks. My understanding is studs were welded to the deck, the boards bored, then nuts used to fasten them down. The holes were then plugged. The boards were bedded in tar. The joints between the boards had a foam backing rod inserted, then some sort of black rubbery adhesive inserted.

Some of the boards have rotted and need replacing. Others have popped up due to rot from underneath causing the nut to no longer hold the board.

The look is beautiful, and a necessity IMHO for the look of the boat. I was wondering if there were any ideas on better ways to fasten, bed, and caulk the boards. Both to make installation and replacement quicker and easier, as well as to reduce the chance of rot.


Thanks,

Allan.

[pdwiley]

Originally Posted by ayates

I have started volunteering on a Brigantine tall ship youth sail training program. Their ship is a steel hull with a steel deck. The deck covered with teak planks. My understanding is studs were welded to the deck, the boards bored, then nuts used to fasten them down. The holes were then plugged. The boards were bedded in tar. The joints between the boards had a foam backing rod inserted, then some sort of black rubbery adhesive inserted.

Some of the boards have rotted and need replacing. Others have popped up due to rot from underneath causing the nut to no longer hold the board.

The look is beautiful, and a necessity IMHO for the look of the boat. I was wondering if there were any ideas on better ways to fasten, bed, and caulk the boards. Both to make installation and replacement quicker and easier, as well as to reduce the chance of rot.


Thanks,

Allan.

If boards have popped up, I'm betting you'll find *rust* under there, not rot. Rust has greater volume than the original steel.

You are in for a pretty nasty time I expect. Start planning on taking all the deck up and starting again.

PDW

[Nick.K]

We have just stripped off the teak overlay from a 65ft steel yacht (with steel deck). The condition of the teak was as you describe, with some soft areas (actually in the plywood sub-base not the teak) and some rust bleeds between joints. The steel deck was originally 5mm but had rusted to practically nothing in places.
You could try going over the deck with a sounding hammer to locate the worst areas and then carefully cut the caulking around the shortest boards and lift to inspect the steel under. As PDW says, if the boards are lifting it is probably rust scale that is pushing them up. Before lifting off all the teak, work through the economics of replacing large areas of deck plate to see if a repair is viable.
Teak or Teak-substitute decks can be prefabricated in large panels which are then bedded on mastic or epoxy.
Nick.

[michael pierzga]

Whatever detail your deck has the steel must be sandblased and epoxy primed before attempting to re lay the new deck or you will be wasting preciuos teak and labour. .

All modern teak over metal decks are laid without fasteners. NO FASTENINGS.

[ayates]

Thank you all to the tips so far. Really appreciate it.

Originally Posted by michael pierzga

All modern teak over metal decks are laid without fasteners. NO FASTENINGS.

Did some Googling on this, and I see what you mean. Lay a plywood base with epoxy, and then lay thinner teak planks with epoxy, with epoxy for the gaps between the boards too.

This is all good to know for a full refit. I suspect though, they will want to just do some repairs to specific boards for the upcoming season.


Thanks,

Allan.

[gonzo]

Epoxy is not the best adhesive; it is too rigid. A flexible adhesive like SABA or Sikaflex is much superior. Vacuum bagging is the way to go. I have done many decks with this system. This is what it looks before sanding the seam caulk.

[eyschulman]

What about the newer flexable epoxy?

[NorCal]

Originally Posted by gonzo

Epoxy is not the best adhesive; it is too rigid. A flexible adhesive like SABA or Sikaflex is much superior. Vacuum bagging is the way to go. I have done many decks with this system. This is what it looks before sanding the seam caulk.

I've been lurking because I'm not a pro and that seems to catch a lot of criticism here but this post has my curiosity going as I would like to put teak decking on one of my boats. Do you have any good references on the vacuum bagging procedure?

I found this basic description: http://www.goodoldboat.com/pdfs/Vacuumbagging.pdf

Thanks for the feedback.

[michael pierzga]

I dont have a good internet connection tonight so I cant search for a link on vacum bagging a teak deck. Its a bit more trouble prone than a simple veneer application on cabin sides.

Commonly you plywood template the deck...move the templates to the shop...vacum the teak veneer to the ply substrate then vacum the teak ply to your deck.

You may also vacum the teak directly to your deck. Ill try next time I get a good connection.

[gonzo]

It is easier to make a template and lay the teak deck on a work bench, then vacuum the panels on the deck.