Radiata Pine for canal boat

[B_Kennedy]

Greetings.
I am keen to build an Escargot canal boat as designed by Philip Thiel, but with a 6hp outboard.
Unfortunately, the Venezia is just too big for me to construct. Sorry Mik!
She is very simply designed being only 18'6" x 6' with flat bottom and sides.
The recommended framing is 4x2 and 3x2 (all dimensions are in feet and inches) and I am wondering if I can get away with using Radiata pine with marine plywood skin.
I am in Tassy and know I should use Oregon, Fir etc. but will have to travel to source some.
What if the Radiata is epoxy coated before painting? Will it stay nice and straight as she will be on a trailer most of the time?
Perhaps I should cut them out of ply and laminate up to the moulded dimensions.
Any advice most welcome. Brent

[ian]

Perhaps I should cut them out of ply and laminate up to the moulded dimensions.
Hi Brent

I think that might your best option.
That or travelling to source Oregon or fir

[B_Kennedy]

Thanks Ian. I have a few days off so will go for a drive and look at alternative timbers. If I had an unlimited budget of course I could use Huon, Celery or King William too! ;-)

[Arron]

My experience with building timber boats is limited to building a wherry, a rowing skiff and a canoe, so I'm by no means an expert. However, when building my boats I had the same question.

I assume you are talking about nice clear radiata, not the knotty stuff.

Personally, I can't see any reason not to use it - except perhaps weight.

Radiata is strong, not overly heavy, machines well, stable once dried, and glues reliably. Treated, it will not rot even when used underwater.

I never actually used it because my builds were too weight sensitive, but I'd like to hear any real reason not to on a build like yours.

I think the plan you have chosen suits (and was designed for) utility materials, not expensive stuff.

[B_Kennedy]

Thanks for the info. Yes, I looked at some DAR 90x45 and 70x45 perfectly straight and knot free. I hadn't considered using Radiata until I saw that. A coat of epoxy under paint wouldn't hurt either. I also found that the New Zealand Zephyr dinghy, designed and built 60 years ago used Radiata pine. Apparently, many are still in good condition today.

[Arron]

I think that when we build boats everyone wants to make them as waterproof as possible but really it's easy to overthink it. If it's a trailer boat and its kept under cover then really it's not a boat it's a piece of furniture that gets wet ocassionally.

I'm not aware of any difference in inherent water resistance between radiata, Oregon and spruce. I think the weight difference may lead people to preference the latter two, but really as timbers they are second rate, especially modern plantation Oregon.

I did envelope-coat my boats in epoxy. I do endorse that - it does work.

I repeat, I'm not an expert. It will be interesting to hear from anyone with genuine experience using radiata in boat building.

[B_Kennedy]

Had a bit of a hunt around and found some Oregon that is imported from Canada. Lots of tight knots and a few $$$ more per metre than Radiata with about the same rot resistance and interestingly, about the same weight. It has tighter growth rings so may be stronger, but I don't think that outweighs the cost in this application.
I might use Radiata for some parts, Tas Oak for others and perhaps some Celery Top pine for the chine runners.
Might ask around at the Australian Wooden Boat Festival in a few weeks. B

[b.o.a.t.]

If you use treated pine, then rot won't be a problem.
Radiata grows quickly & is therefore not as strong as slower growing species with tighter growth rings.
Radiata probably makes sense as a filleting material in chine logs & sheer clamps.
Would have thought Tas Oak the better choice for chine runners & outwales - harder wearing.
cheers