Skin on frame canoe

[heavyweather]

I am building a canoe with some 12yr old students of mine. It will be 4m long. We got 4m of larch for the gunwale... what dimensions should we cut that? Stringers will be larch too. The ribs oak for easier bending ( again what dimensions?) or pine, which one should we use? How many ribs should we put in? I guess about 15-19?

Thank you, Marcus

[jsjpd1]

I built a 3m SOF row boat winter before last, the frames were 6 inches on center. The gunwale was 1 1/2 inches by 3/4 inch and the frames were 3/4 x 3/8 inches.





It worked out well.

Good luck,
Jim

Jim

[heavyweather]

Hi Jim,

Looks very nice. Do you think you could have gotten away with less ribs? I guess we will try 8mmx20mm ribs, 35mmx15mm gunwale and 20x10mm stringers.
Any hints on the lashing? I got 1/2oz of artificial sinew...guess thats about 275meters...should be enough? What did you use for the skin?

[jsjpd1]

For the skin I used 8 oz polyester painted with spar varnish. But there are other options available. I'm not sure I'd go with fewer frames, it's already a pretty light weight structure.

Here's a link to the thread I put together while building this boat, you might find it useful.

http://forum.woodenboat.com/showthre...oat&highlight=

Are you building to a plan or just winging it?

[James McMullen]

I think more ribs that are fairly closely spaced are safer for your structure, marcus, as they help distribute and share the stresses so that the individual small pieces of wood that make up the frame don't get too much point loading. I would look at the Geodesic Aerolite boats page and check out the number and spacing of the ribs in their similar sized canoes for an idea of what has been proven to work.

[kfranklin]

Hey HeavyWeather, what design are you going with? I am planning to make a SOF something starting in a few weeks when I graduate.

[heavyweather]

We do not have any plans. We could probably go with one of the plans from gilpatricks book on strip canoes that I bought. Other than that there is so much information that I can't justifie 55$ for plans.
We spent 16€ on wood, 35€ on a wallpaper steamer, 16€ on sinew and will need some more money for skinning if we don't go with the 1.60€\m2 pond liner.
We will sell the boat off on our homepage if it is a success and try another with more budget next time. Got the oak for free though.
Maybe somebody here got a design hor you, then I'd be interested too

The boat will be 90cm wide, 4m long, 35cm deep and very flat bottomed.
We just hope it swims that would be a success.

[heavyweather]

I have probably found all sof canoes on the web by now...


If you are looking for ultralight go here.

http://dbynoe.blogspot.com/search/label/Canoe
The plans are free as long as you don`t sell them (plans or boat).

http://dbynoe.blogspot.com/2011/03/canoe-sculpture.html

These frames are so simple and beautiful.

We go with a flatter boat though. There are no waves here and no wind either. We need a stable boat.

[heavyweather]

What I am not so sure of is that sewing detail.
http://4.bp.blogspot.com/_bXDvvbP-Wv...600/Thwart.jpg
I would rather like the cloth to be sandwiched between outer an inner gunwale.
Maybe I mortise the inner Gunwale to take the ribs and screw on the outer gunwale over the cloth.

[kfranklin]

I haven't built one myself, but I always have seen SOF canoes with the skin over the gunwales in a variety of forms never sandwiched. My thought as to why is because if you sandwich it, you need to remove a gunwale to replace the skin. (This is just a over-educated under-practiced hypothesis!)

[heavyweather]

I have seen it sandwiched on some boats. As I understand there ist a line woven in the edge that holds the cloth above the gunwales. Don`t know how they do that exactly though.
Heres that SOF Andirondack ...the ribs are not in the gunwales on that one though.
http://www.capefalconkayak.com/adirondackguideboat.html

My students are not that into perfection anyways

[Gravy]

Long time reader, first time poster. Remember back in 2008/2009 the solo carry canoe in WBM? Hilary Russell wrote a 2 part article on a SOF canoe. I knew he runs the Berkshire Boatbuilding School (berkshireboatbuildingschool.org) in Sheffield Mass about an hour from here, AND had just written a book - so I rode up to meet him and get a copy. Nicest man (so's his wife), answered all my questions, and gave me a tour of his shop. We talked for probably more than an hour. Might check him out, as well as his book, which I'm about 2/3 through.
BTW just skinned my Gentry Shenandoah Whitehall last weekend.

[kfranklin]

I have seen it sandwiched on some boats. As I understand there ist a line woven in the edge that holds the cloth above the gunwales. Don`t know how they do that exactly though.
Heres that SOF Andirondack ...the ribs are not in the gunwales on that one though.
http://www.capefalconkayak.com/adirondackguideboat.html

My students are not that into perfection anyways

OH Sorry Now I get what is going on. When I talk boat I translate gunwale to inwale-outwale. Most true classic canoes have a inwale-outwale combination. On SOF canoes the skin goes over the two. Outside of this is attached a rubrail that isn't there for structure, but protection. The Adirondack guide boat (at least the one in the line) has the gunwale on the inside with a rubrail over the skin. I hope that makes sense, but least that is what I've seen. It makes sense to me because if you have to remove a outwale, that impacts the structure, versus a rubrail which is cosmetic.

[heavyweather]

I see...my fault. So thats a rubrail.
Is there any advantage off sandwiched ribs vs. mortised ribs in a single gunwale?

[kfranklin]

Btw, it was my fault for using ambiguous language!

[James McMullen]

. . . I can't justifie 55$ for plans.

We just hope it swims that would be a success.

Seriously? You're building a boat of a type and a style that you don't have any experience with and you think $55 is too big of an investment?

Seriously?

No really, seriously???

You are being penny wise and pound foolish. That fitty-fi bucks could be the best money y'ever spent, amigo. How much will it cost you to build a crappy boat the wrong way for practice instead of just doing it right the first time? Are you really that broke?

[heavyweather]

James. I guess you never worked at a public school.
55€ for plans when all the material is there?
There is no money for toilet paper and the parents could not care less what there kids are building or not...they are even less eager on spending money for them building a boat that is owned by a group.
I`v spent money on material, tools and not so little of my private time to drive around, get wood, milling the wood and testing things. Thats for one class.
If everything works out we will have more money and support next time.
The boat itself is not the prime focus in education. Besides it won`t turn out crappy.

[Frank R]

Ditto on the plans price. Best money you will ever spend. The Geodesic plans are nice; full size patterns for the frames.

[skuthorp]

This site and it's pics may be of interest and use to your project.
http://www.garyjacobson.org/canoe/

[Cuyahoga Chuck]

This site and it's pics may be of interest and use to your project.
http://www.garyjacobson.org/canoe/

This is a Geodesic Aerolite. It's an ULTRALIGHT. It's built using technology from ultralight aircraft. To stiffen the frame the whole thing is trussed with Kevlar roving. Without the Kevlar this framework is incomplete and could be unsafe. And suggesting there is something that can be extrapolated to a hull being built with traditional Skin-on-Frame techniques is a leap that shoudn't be made. This is a lightweight boat for light loads, mild water and careful handling.
I can't be sure but the position of the thwart suggests this canoe is only a 12 footer which would only have enough room for a single occupant.

The only plans for a SOF canoe I've seen were done by an SOF expert, Robert Morris. He recommends ribs of 1/4" x 1½" on 8 inch centers or ribs of 1/4" x 3/4" on 4 "centers. So the boat in the picture should have about twice as many ribs if it were being built to carry a standard load for it's size. With an SOF framwork such as this all the elements have to share the load and impacts. If one element breaks the rest have to be able to shoulder the load and carry on.

[Canoez]

Seriously? You're building a boat of a type and a style that you don't have any experience with and you think $55 is too big of an investment?

Seriously?

No really, seriously???

You are being penny wise and pound foolish. That fitty-fi bucks could be the best money y'ever spent, amigo. How much will it cost you to build a crappy boat the wrong way for practice instead of just doing it right the first time? Are you really that broke?

Sorry, Heavy, but I have to say "AMEN BROTHER!" to James' comment. Part of the education is to know to work from proper plans - particularly if it's something you've not done before. I know that it isn't a trivial amount of money, but perhaps a small student fundraiser would be allowed to help with such an expense?

[Bram V]

Problem is also, that, even if you have a boat that works, someone might get inspired, but think he/she can do it even lighter, then test it and have the boat sinking. I'd say but the plans, maybe a few, build off the plans at first, if you have a very good idea what choices are made and why, make your own design.

I did not do this, and my boat will be more expensive (a few mistakes and redesigns), and perform less when finished, for me it was not the result that matters, it was the thinking, testing and building I wanted, the boat is just a byproduct of that.

[kfranklin]

This is a Geodesic Aerolite. It's an ULTRALIGHT. It's built using technology from ultralight aircraft. To stiffen the frame the whole thing is trussed with Kevlar roving. Without the Kevlar this framework is incomplete and could be unsafe. And suggesting there is something that can be extrapolated to a hull being built with traditional Skin-on-Frame techniques is a leap that shoudn't be made. This is a lightweight boat for light loads, mild water and careful handling.
I can't be sure but the position of the thwart suggests this canoe is only a 12 footer which would only have enough room for a single occupant.

The only plans for a SOF canoe I've seen were done by an SOF expert, Robert Morse. He recommends ribs of 1/4" x 1½" on 8 inch centers or ribs of 1/4" x 3/4" on 4 "centers. So the boat in the picture should have about twice as many ribs if it were being built to carry a standard load for it's size. With an SOF framwork such as this all the elements have to share the load and impacts. If one element breaks the rest have to be able to shoulder the load and carry on.

Where did you come across those plans? (I hope note his amazingly rare out of print book)

[Cuyahoga Chuck]

Where did you come across those plans? (I hope note his amazingly rare out of print book)

Yes. I am one of the fortunate few. I also have Wolfgang Brinck's out-of-printer.
Morse's book is a real treasure chest. I hear he even teaches kayak building to Inuits.

[kfranklin]

Yes. I am one of the fortunate few. I also have Wolfgang Brinck's out-of-printer.
Morse's book is a real treasure chest. I hear he even teaches kayak building to Inuits.

Drat! Why is it not in pdf form?

[2MeterTroll]

SOF canoe; what plans have you got for it? what style are you building? I might have a plan or two around here. as James said the plans are a great investment. if you want fewer ribs you need to have wider ribs, no real savings in wood there. You building with 12 year olds? they can do some really fine work but i think i would start with an umiak; far more robust and useful than a narrow canoe.

Good on ya have a fun build.

[Three Cedars]

http://www.woodenboat.com/wbmag/laun...S_Entry_id=490

http://www.jonsbushcraft.com/Article...0tutorials.htm

The grand old man of skin on frame boats , Percy Blandford has plans for a SOF canoe in his book "Canoes and Canoeing"

[Cuyahoga Chuck]

http://www.woodenboat.com/wbmag/laun...S_Entry_id=490

http://www.jonsbushcraft.com/Article...0tutorials.htm

The grand old man of skin on frame boats , Percy Blandford has plans for a SOF canoe in his book "Canoes and Canoeing"

These plans are the full size patterns for Blandford's 16' "Teal". $30.
http://www.clarkcraft.com/cgi-local/...c8bc6fb0a456bb

[JohnC]

Try borrowing Robert Morris's Book on building SOF boats from the library - it has a lot of your answers for you. It's out of print so the library is the only option.
This is a nice canoe based on the lines in Adney & Chapelles Bark and Skin Boats of Nth America - Another good book to study for canoe lines


http://www.flickr.com/photos/michael...7627188547433/

John

[Greg Nolan]

Check your private messages.

You should check out the website of the Wooden Canoe Heritage Association -- WCHA.org -- where you will find some useful information about SOF canoes.

[Three Cedars]

Ditto on Adney and Chapelles book , the bible for canoe drawings.

The Robert Morris book does include a canoe but as Morris himself has said the canoe hull shape shown is too rounded .

[heavyweather]

Check your private messages.

You should check out the website of the Wooden Canoe Heritage Association -- WCHA.org -- where you will find some useful information about SOF canoes.

Hi Greg, did you get my message? It indicates I answered but it is not in the outgoing folder..
I've already been at the WCHA website last week and found the information very interesting.


I've read anything I could find on the Internet on SOF canoes, kayaks and related information on construction and design, but I am sure there are hundreds of built reports more...

There might be some really perfect designs, hulls and plans but I figure you can just go on and start building a boat. We will keep the bottom really flat, very little to no rocker, lots of ribs and rather opt for a tough build than lightweight design.
I have designed a squirt boat in Rhino some years ago but got more experience in that direction of boating.
When I was around 13 yr old I built a small canoe from green wood on my own. It was all hazle. I still got the thing , might also have a picture somewhere.
edit: here we go: http://666kb.com/i/c3bvfemydvx9pca87.jpg
Safety is not really a question. The boat will never be used for touring or anywhere else than a small lake. It might see the water some times but it probably will be hanging in the school for display...more a sculpture and inspiration.
We might go on from there and will probably buy plans for the next boat...

It`s also a question if it will be possible for the children to finish the boat in their regular classes. We only got some weeks left and my priorities are a little shifted this month...my second son is going to be born around mid Mai...

Thank you guys for that helpful thread and that great forum.

[2MeterTroll]

From experience you might want to focus on the learning part and not on the finishing part. folks trying to finish a kids boat often dont understand what the kids want and take the project over. However; you can diffuse that dynamic if you teach the boat whit the idea that it will be finished in it's own time. Encourage good work and completion not the object. its a fine distinction I know, but the kids get it.

[potomac]

First, I really applaud what you are trying to do here. As a former teacher, I have to say it was the times building things with students that really provided the best educational opportunities for my kids. There was something about figuring things out together that not only got to the heart of the problem, but also fostered a belief that my kids could figure anything out if they put their minds to it. The tricky thing about boats is, the thing you are building is for use in a foreign environment where failure equals putting kids' safety in jeopardy. I know you know this. I was a drama teacher before becoming a NYC cop, (weird right), and I know the way we built sets that was just for show vs. the way we built a set that would allow a kid to sing and dance from a second-story balcony was completely different. I think in a lot of ways, water is easily the equivalent of that second-story balcony. Additionally, if you have the intention of selling this boat, you have a responsibility of creating a safe, seaworthy craft for your customer. That's part of the lesson for your students.

I have a couple suggestions:

1. I'm not sure how far along you are, but I would strongly suggest you check out our own Dave Gentry's website as well as Tom Yost's. I think their building style, which while not being the most traditional, is very doable. My experience with Dave Gentry's plans is that they can easily connect to all sorts of fields of study- definitely math, physics, and reading comprehension. Clearly literature, earth sciences, art, and social studies are not far behind.

2. Talk with your school librarian and see if you can't get them to make plans part of their collection. Plans usually offer license for a single hull, but subsequent hulls are usually much cheaper and would be a very small expense.

3. Write a grant. This can be a tough one, but you don't always have to go the traditional route for looking for funds. If your department, school, district, parents don't have the money or interest, look to local businesses. I get this. I was starting a Drama program in a country high school that was designated an agricultural magnet program. We literally had cows and pigs on campus. When starting a fledgling program, I went with advertising and slowly built from there

4. Reach out to local news agencies. They love stories like these and the positive publicity that goes along with being associated with such a neat project often brings sponsors out of the woodwork.

5. Treat this as a business- eventually. That's an additional lesson for your kids and insures a self-perpetuating program.

6. Remember, good teaching is both content knowledge and pedagogy. I'm sure your district wouldn't hire someone who had simply learned all they needed to about teaching by reading some internet articles. It doesn't cost anything to put some information on the web and likewise, there's not really anyone to make sure the information you are getting is good. A real, professional designer really has to have some credentials. This is a great lesson for your kids too. They are being bombarded with information all the time. Not all of it is good. This is a good way to teach them to consider sources and research credentials.

You are doing a neat thing. It's a good thing and this sort of idea is at the heart of really good teaching. My experience is that twenty years from now, you'll still be hearing from those students, saying, "Remember when..." You will. Good luck- Aaron

http://gentrycustomboats.com/

http://yostwerks.com/

[heavyweather]

I have found a Plan now. There is the "Laker" in gilpatricks book. It can be built 4m instead of 490cm by omitting 2 stations.

[heavyweather]

We got no time left this semester. The kids tried some bending. They are not really very patient steam bending did not work really well. We also do not have good wood for steam bending. 8mm fir worked some times. They also tried dry bending some 4mm spruce which worked very well. Anyways we have to do it next semester. Then I will cut up the wood for them and we will make some small craft with plywood frames. Maybe the Ruth can be modified to make it a little shorter?


I will try to get the thing together anyways. I omitted another station and set up 3 stations on a 4m 75mm square. Used the 20mmx20mms larch stringers I had cut and now I will bend in lots of 4mm spruce ribs. Let's see if it works with the cheap wood and bad building I am doing. Will add some pictures when I am not writing on my mobile.

[heavyweather]

http://forum.woodenboat.com/showthre...-chool-projekt

Wie did it.
Dave Gentry was so kind to donate his Whitehall plans.

I am hooked now.
Need to built a very small sailboat next. I got Bolgers "small boats" and drew the "Mippet". After all Dave has done that boat successfully in sof. But after looking around I am having second thoughs. Maybe a sof pram would be cooler. The selway Fischer boats look good or maybe just an Opti? It should be very light, good capacity, not too slow (well, I guess they are all slow at that length) and maybe free plans (would speak for the options again...a rounder hull looks better to me though).
Any ideas?

[jazzalbart]

These are nice looking boats, and hard to beat for fun and utility. I heard that these skin on frame kayaks are perfect for whitewater. I hope your design can help us to make more fun into the water.

[Wooden Boat Fittings]

A real, professional designer really has to have some credentials.

Yes, but remember it depends on the 'credentials' -- Percy Blandford had no academic qualifications in boat design (let alone naval architecture), and neither did/do Phil Bolger, Iain Oughtred, David Payne, Dave Gentry, or many others in small-boat design (AFAIK.) The question that matters is not What You Have, but What You Do With What You Have. All these are/were competent and successful designers, and their designs have been used and reused successfully by many builders over many years.


And congratulations and thanks also to Dave Gentry for donating plans. I think that was a very generous gesture.

Mike