Which timber underwater?

[ErikBenson]

I plan to fit rubbing strips under my 1953 wooden boat, just under the chine. The boat is 16' and mahogany, but this might be a bit too soft. Of course teak is out. Which wood would you suggest. . ..oak ?. . .elm ? I would do Canadian Rock Elm if I could find it. . .alternatives ?
Thanks

 

[johnlilley]

Hi there
quite a large choice really, but most would suggest iroko which is very durable, quite hard wearing and available. Some cuts of it are not easy to work but hold screws well. If you can choose your sections, the lighter coloured initially the easier worked, the darker it is the heavier & more unwiledy it is with more silica included that blunts saws. Turns teak colour after exposure to air/light.

Oak is fine but causes ferrous fastenings to corrode.

Elm was used for underwater components for decades & is quite hard wearing & durable provided it remains immersed.

Sapele/utile is hard enough & reasonably durable although expensive ish.
Ash definite no as it will decay as will beech.

Keruing is very hard and difficult to work but fine for this application & should be cheap.
Jarrah (used for sleepers) very hard & heavy & very durable. Perfect for keels.

There is a link on my website to timber uses/identifiation & properties. Be surprised how many different species of timber there are out there. Go to links tab & timber.


John Lilley

 

[ErikBenson]

Which timber underwater

BRILLIANT John ! and what a great reply in 10 minutes. . .love this website !
I planned to fix them with demountable mastic and silicon bronze screws. I also thought to put them on in scarfed sections so I could replace in the event of over wear or damage.
I'll check out the supply of Iroko and oak in the local suppliers. . .I am near Cognac in France, and it is for my ex RN Fast Motor Dinghy - FMD.
Thankyou , once again . . .Erik

 

[sarabande]

Elm has been used for water pipes since Roman times, and for wharf pilings - but as JL points out , it's underwater.

I'd be tempted to go for green oak - and there are lots of suppliers in SW France.

Have you thought of steaming the wood to shape, rather than using small shaped/scarfed sections ?

 

[ErikBenson]

Which timber underwater

Green oak sounds fine. . I'll have a scrat about. I just thought to scarf in case I had to replace sections.
Actually i, being a COMPLETE beginner , am hoping that my idea isn't a no-no in boaty circles.
Here's my boat