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teecee2008
9th April 2015, 08:28 PM
I am considering making a SOF canoe from Dreamcatcher boats, they specify yellow cedar for there stringers and frames we do have this timber here I was considering using Oregon. Any comments on its bendability for the frames some tight bends or perhaps an alternative.

cheers
Teecee

labr@
9th April 2015, 09:33 PM
I'm not sure about the bendability of Oregon but you could probably use it by laminating thin strips, a bit like making a coaming for a kayak. This would apply to many timbers.

Another, possibly more important, question is how it will stand up to getting wet. Personally I would use western red cedar or paulownia coated with tung oil (the straight oil not the "tung oil finish"). On my SOF kayak I used epoxied WRC for the laminated coaming and oiled paulownia for the stringers and it's a case of so far, so good.

No experience with bent ribs though as I used a plywood frame design from Kudzu.

Don't forget to post up some photos when you get started.

teecee2008
9th April 2015, 10:35 PM
Thanks for the info, I have used both Wrc and paulownia on a stripper I built a few years ago and I am not not sure as to the strength of both in a canoe situation. Guess I need some more thought.

Nanigai
10th April 2015, 12:56 AM
G'day teecee2008, firstly welcome to the forum, hope you enjoy it.

I have been reading up on kayak & canoe building and am about to start my first project, a stand up paddle board.

Have a look here (http://www.dpi.nsw.gov.au/__data/assets/pdf_file/0005/390299/Timber-in-Boatbuilding.pdf) for some info on timber used in boatbuilding in Oz, it's a paper written by the NSW DPI. It advises on the timbers to use for different parts and which bend better etc.

From timber.net.au they say about Oregon "Care is needed in dressing because the softer earlywood may be compressed and later, on recovery, produce a ridged surface. This characteristic makes it unsuitable for steam bending."

I like abr@'s idea of the WRC or Paulownia treated with Tung Oil, I would go with that. An alternative but similar

idea is to use epoxy in place of the oil to improve on strength but I personally wouldn't bother.

Anyway you go best of luck, dont forget the photos :U

Cheers, ian

whitewood
11th April 2015, 09:02 AM
Quote

I like abr@'s idea of the WRC or Paulownia treated with Tung Oil, I would go with that. An alternative but similar

idea is to use epoxy in place of the oil to improve on strength but I personally wouldn't bother.

Anyway you go best of luck, dont forget the photos :U

Cheers, ian




[/QUOTE]
I sold Paulownia for some time and many of my customers used it to build surf and SUP boards. One builder didn't use epoxy and put his foot through the board when he sprang up while catching a wave. To get a board strong enough you would have to balance - framing, thickness of the skin timber and your weight. The usual practice with most of my customers was to use epoxy unless it was an alia board.

Whitewood

labr@
11th April 2015, 05:10 PM
Just a word on the effect of epoxy on strength - on its own epoxy will give very little, if any, strength improvement. With strip built kayaks/canoes/surfboards the surface is covered with fibreglass and epoxy, not just epoxy. The glass cloth is what really gives it the strength and the material becomes a composite. Teecee, you would know that already given your experience.

Obviously with SOF construction, covering each rib with glass/epoxy is not practical. Where epoxy would be useful is in laminating the ribs from very thin strips. I think you would end up with a good strength (and rigidity) to weight ratio. There is more glueing work to do but the bending is easier and the timber is less stressed so breakage is not a problem.

If you decide the ribs are too much work then you might have a look at the fuselage frame style of construction which uses ply wood frames. There are 2 canoes in the range at Kudzu Craft and while these are not as elegant they still look quite good and are a quicker build.
http://www.kudzucraft.com/designs/canoes.php

At least 1 has been built in Aus, Wollongong to be specific, and Meranti was used for the stringers. Here is a Kudzu forum post on the launch:
http://messing-about.com/forums/topic/9183-maple-my-stonefly-is-on-the-water/

Danielvn
5th May 2015, 11:29 PM
I'm in the process of arranging Kiliii Fish of Seawolf kayaks to present a workshop in Sydney during August. Participants will each build their own SOF kayak and a Greenland paddle during the eight day workshop. Message me if interested for more details.

Daniel

Jim Eustice
6th October 2015, 02:56 PM
Adelaide, Sth.Aust.. Have just purchased some paulownia for stringers on a Dave Gentry Chuckanut 15 for my wife and I to use. Have to make the paddles first,
what timber etc. recommended for them in Australia?
Jim

anewhouse
6th October 2015, 03:59 PM
Are you planning a greenland paddle? I have been using one for about four years made from Paulownia. I have also made them from WRC. None of them have developed any problems.
I have tips added on the ends made from whatever denser timber I can find at the time; tas oak, jarrah, myrtle.

Jim Eustice
12th October 2015, 07:31 PM
Yes, greenland or Inuit style. Have been checking various information on line. Puchased Rob Mack's patterns as a further guideline.

anewhouse
13th October 2015, 06:58 AM
One thing that discouraged me from building a greenland paddle was the thought of how much timber simply disappeared as shavings if it was built from a single piece of 100x50.

Then I found this idea. https://sites.google.com/site/kayakamf/making-greenland-paddles

Starting with a 100x25 seems much less wasteful. :)

Jim Eustice
19th October 2015, 01:05 PM
Thank you.