Small Kayak for Backwater Canals ? [Archive]

ancient kayaker

11-24-2008, 03:18 PM

I like to build one, for using on the backwater canals. It's still water, not flowing, so I'm looking at a small Kayak Like boat. Like to get some suggestions from this forum.

1. Looking for it to be light. Very Light. say about 7 to 20 KGs.
2. Content with a single cockpit, but two would be nicer.
3. thinking of a skin on frame? Kayak
4. CHEAP. say about $100 max.
5. Will use it for weekend trips, just to paddle around few KMs and back. Dunno if I would be camping etc...

. Please give some ideas, if this thread is not the right place, mods please uproot my post and create a new thread for me.

cheers,
MS

A lot depends on what supplies are available in your country. Here in Canada it can be done within your parameters. I have built several canoes 11 to 12 ft long, less than 10kg for $50-100 each, using 3mm marine plywood. I do not fiberglass them since that adds weigth and cost; I reinforce the seams with 3/4" sq softwood chine logs. Ply canoes are lighter than kayaks, for a given construction and size; the deck adds about 30 or 40% to the weight and cost. These canoes are very quick to build, about 50-60 hours for me (amateur builder), fully finished with wood seat ready to launch. It doesn't have to be marine ply but must be good quality and not too thick, 3-4m is ideal. If you can get the materials I can share one of my designs.

A popular canoe type is built with cedar strip; this costs more and takes longer, and must be fiberglassed to provide across-grain strength. It would be advisable to buy a professional design.

It is also possible to make a skin-on-frame boat, in that case a kayak is a better option since the deck adds stiffness. Canvas used to be used, with a paint formulated to stay flexible, but there are more modern materials available which are tougher and shrink when heated for a better finish.

Whichever you chose there are several sites on the web you can find by Googling.

Are canals used commonly for small boats in India? In the UK they can be quite busy at times, in Canada they are mostly ideal although my nearest one is too polluted as a result of passing through farmland with intensive growing methods. However, in this part of canada we are blessed with an abundance of lakes that are perfect, although not for the next few months due to a seasonal hard water problem!

millionswords

11-25-2008, 01:18 AM

A lot depends on what supplies are available in your country. Here in Canada it can be done within your parameters. I have built several canoes 11 to 12 ft long, less than 10kg for $50-100 each, using 3mm marine plywood. I do not fiberglass them since that adds weigth and cost; I reinforce the seams with 3/4" sq softwood chine logs. Ply canoes are lighter than kayaks, for a given construction and size; the deck adds about 30 or 40% to the weight and cost. These canoes are very quick to build, about 50-60 hours for me (amateur builder), fully finished with wood seat ready to launch. It doesn't have to be marine ply but must be good quality and not too thick, 3-4m is ideal. If you can get the materials I can share one of my designs.

A popular canoe type is built with cedar strip; this costs more and takes longer, and must be fiberglassed to provide across-grain strength. It would be advisable to buy a professional design.

It is also possible to make a skin-on-frame boat, in that case a kayak is a better option since the deck adds stiffness. Canvas used to be used, with a paint formulated to stay flexible, but there are more modern materials available which are tougher and shrink when heated for a better finish.

Whichever you chose there are several sites on the web you can find by Googling.

Are canals used commonly for small boats in India? In the UK they can be quite busy at times, in Canada they are mostly ideal although my nearest one is too polluted as a result of passing through farmland with intensive growing methods. However, in this part of canada we are blessed with an abundance of lakes that are perfect, although not for the next few months due to a seasonal hard water problem!

@ ancient-kayaker :

1. I go between Bombay and Chennai [Bombay/Mumbai is on the west coast and Chennai is on the East Coast]
2. Both big metropolitan cities, and availability of materials is not a problem
3. Around Bombay there are small seasonal rapids, and backwaters. Mildly used for transport but not much of traffic, not crowded.
4. Off Chennai[Madras previously] has good scope for backwater activity, but not much is used, it's kinda pristine and if I'm kayaking I will be a lone Kayaker!
5. It's peaceful, lots to be explored, would be nice during the monsoons and summers are real hot. July, Aug, Sept, Oct would be ideal for some activity.
6. Cedar strips or spruce roots - I dunno if available, may not be around. But there is quite a lot of other timber that we can source.
7. Epoxy, Resin, Gum, hardware, tools are available in plenty. What I need is the big confusion here.
8. With some guidance and some one to clear doubts as it arises I should be good.
9. Fiber glassing too can be done, materials are available [I have seen and been around when doing some car mods, for stereo ICEing.]
10. From what I see, choice1 would be SKIN ON FRAME or go for the Plywood Kayak - ply is available in plenty of choice here.
11. Inflatables and Fibre Mould are used here mostly, like in the Himalayan Rapids and some rapids down south around Bangalore[350KMs from Chennai]
I want to build mine, unique :D
12. So let us drop the idea of Cedar strips or pure wood Canoes.
13. Let me see how to do a SKIN on FRAME Kayak, if the materials are unavailable, I will look at PLY.

Hi MS,

What you describe is quite common around here. There are dozens, if not hundreds, of small, slightly beat-up kayaks and canoes all over the place in Ontario; we have a lot of small, calm lakes and rivers for which these boats are ideal. Of course, that doesn't do you much good being in Bombay....

Two of your requirements- #1 and #4- are contradictory. It is very difficult to get an ultra-light boat that is also under $100. You may be able to build a skin-on-frame kayak yourself for this, if you don't mind scrounging for supplies a bit. I think you might be better off trying to find a small, used fibreglass canoe, if you can.... but I don't know how common they are in your area.

Thanks for the reply Matt.
yeah #1 and #4 are important, and not impossible.
You are band right, a Skin On Frame is the idea, please share any info that might be useful for me to start with. I wish to build one, I have the time now.

I don't mind procuring the materials, which is available in plenty here in India, tools, material and anything else.

Used boats? - lol I would be the first to be Kayaking on these waters I suppose! :D

MS,
I think the cost requirement is difficult to handle for us who don't live in India. Cost levels are different in India compared to Canada (or Sweden). You'll have to avoid imports and find something locally produced, probably not intended for boats, that is suitable for building a boat. If you can get hold of cheap epoxy you have a good start and you can then use building techniques that are commonly advised on this forum.

Impregnated cloth as skin for a kayak ought to be cheap, except I have no idea which cloth or which impregnation that are suitable and locally produced.

Good luck,
Erik

Yep, I second that. Let's leave the cost behind. Don't worry about the cost, please share with me alternative material that I can use, I will keep posting what is available here at what cost, so that we can work out something close to $100 or so. I'm not very strict about the cost now because it will be a first timer's job and hence I understand the complications involved. I have no prior experience in Carpentry but have hands on experience with Plumbing, Mechanical and some Electrical works. I think I can pull it out with some trial and error attempts.:idea:

millionswords

11-25-2008, 02:39 AM

some doubts:

1. Epoxy - I know the Epoxy Adhesives available here, is this the Epoxy we are talking about in Boat Forums? coz there is some Epoxy for varnishing too? isn't it?

2. TIMBER: Timber pertinent to our continent is available in plenty [Palm, Rosewood, Mango, Jack, Deodar, Banyan, Babul, Lauraceae, tamarind(in plenty), Toona Ciliata(red cedar), Pine, Simul Bombax].

I dunno which is cheap. But if you guys tell me which ones to drop out, and which ones would suit best in some order of priority, I will find out the prices for them all. Then decide the value for money timber and go from there.

I thought these are the first primal requirements of material, once these are decided and spot on, we will be good to go.

EDIT Update:

BAMBOO
I went out to check what is available to suit this project, first to the Bamboo Furniture stores:

1. I found that there are bamboo sticks either hollow or [semi ]Solid. The smaller Solid ones are used to make furniture, and structures.
2. The bigger hollow ones are used to strong hold structures, it is less usable in this particular project. We can make strips out of the bigger ones.
3. Bamboo is affordable, value for money. about $1 for 15 feet. Isn't that nice?
4. So now we need to know how much bamboo is required, what type (green or dry), usually we get the semi-dry ones easily.
5. Bending bamboo in itself seems to be an art, I need a heat gun, and some sort of home made vice.

Cedar Wood!!

I inquired about some wood that will give the flexibility to bend, some 4mm thick and bendable.
I found some wood, closely called like Devdar Maram [or something like that in local language Tamil]is light and used heavily in cheap furniture making, is resistant to rotting.
When I came back and searched for Indian Timber that is close to this name I found it to be Cedrus Deodara, a Cedar family! So we have a close match to the Cedar here. But This is grown in the North Indian Himalayan range and must be expensive to procure. Will check with some timber merchants tomorrow or so and update here. But let me keep this for the next project some time later.

Will go on with the Bamboo idea now.
Attached is an example of how I intend to get the bamboo frame done.

S K I N[/SIZE]
Now with the frame in place - what material to use for the skin?
Options are:

1. Canvas - dunno the cost, must be expensive
2. Please suggest something here
3. Propylene Sheet
4. Tarpaulin (http://en.wikipedia.org/wiki/Tarpaulin)/Tarp sheet [hootchie in OZ] - ValueFM
5. Polyethylene Sheets - VFM

The above are available and easy to procure. Please suggest a treatment for them, and how to finish the skin?

Oh yeah, on how to fasten them to the frame? - a big doubt that still lingers in my mind. Nails would work, bamboo threads can be made and used to tie them down. Would you all suggest something so that I can put it on and off the frame? would it be okay to do that? or should I keep it permanent on the frame?

MS

PS: Hope I covered a lot here, please throw your ideas. Love to hear from you all. Thanks again.

ancient kayaker

11-25-2008, 11:43 AM

If there are rapids involved and you are an inexperienced paddler a kayak is a better choice than a canoe.

Recalling the problems faced by a would-be boat builder in Thailand, I thought it possible that timber might be expensive or unavailable to you so I was going to suggest an aluminum-frarmed skin boat as per George Dyson's book "Baidarka, the Kayak". The book should be available over the internet, and would provide you with several designs plus a detailed description of the method and details of materials. I would imagine you could substitute bamboo for the Aluminum stringers used by Dyson easily enough, with a little experimenting. Aluminum tubing can be bent permanently unlike bamboo, so those parts made of bent Aluminum, also Aluminum plate could be changed to plywood. I would think green wood to be easier to bend and would gain strength as it dried but it sounds like you have experts on the care and feeding of bamboo that can advise you. Dyson uses bindings to secure the stringers to the frames rather than screws which are more common for wood-framed skin boats, and that would probably suit the use of bamboo.

As you have found, canvas is expensive. I know there are better, cheaper and lighter materials, there is information in Dyson's book. You need something that will stretch, to enable you to get a smooth surface as well as to resist knocks and rocks. Most non-fabric plastic sheets or pre-sealed sheeting like tarp lacks flexibility, although you can use tarp as a cheap temporary covering to test the boat before investing in better materials. I have not built one of these boats but I know that the material is not nailed to the frame below the waterline; I believe it is applied in one piece, sewn at the stem to achieve the shape, and secured with a rubbing strip screwed to the gunnels, then heat-shrunk and sealed. That would apply to a wood framed boat of course. You might find Dyson's methods better suited to bamboo which is rather hard and not flat.

There is a picture of a skin-over-frame boat in the last post of http://www.boatdesign.net/forums/projects-proposals/challenge-100-boat-12176-7.html, it has a plastic skin but the builder is planning to replace that with nylon fabric with a polyurethane sealant.

I suppose I shouldn't advertise the competition but you have a better chance of getting experienced help on this topic at this specialised kayak forum: http://www.kayakforum.com/

Good luck with your project!

millionswords

11-26-2008, 10:33 AM

If there are rapids involved and you are an inexperienced paddler a kayak is a better choice than a canoe.

- There are no rapids in Chennai and it's backwaters. I'm looking at a Kayak in this first step. Let me build a nice canoe later, with good timber(cedar)

Recalling the problems faced by a would-be boat builder in Thailand, I thought it possible that timber might be expensive or unavailable to you so I was going to suggest an aluminum-frarmed skin boat as per George Dyson's book "Baidarka, the Kayak". The book should be available over the internet, and would provide you with several designs plus a detailed description of the method and details of materials. I would imagine you could substitute bamboo for the Aluminum stringers used by Dyson easily enough, with a little experimenting. Aluminum tubing can be bent permanently unlike bamboo,

- Bamboo can be bent permanently too. It's strong and durable! It won't rot soon, with few coats of varnish it will last much better.!

so those parts made of bent Aluminum, also Aluminum plate could be changed to plywood.

- I would think over this idea of Ply in place of the bamboo rings.[you call them ribs?]

I would think green wood to be easier to bend and would gain strength as it dried but it sounds like you have experts on the care and feeding of bamboo that can advise you.

- yeah true, I would get the right advice from the right people on what type of cane to but and cure. Green would be better from our logical perspective, dunno if we are right or wrong.

Dyson uses bindings to secure the stringers to the frames rather than screws which are more common for wood-framed skin boats, and that would probably suit the use of bamboo.

- yeah, I saw some neat bamboo barks peeled and used as bindings. Would attach a image here under.

http://img370.imageshack.us/my.php?image=img5793ai2.jpg
http://img201.imageshack.us/my.php?image=img5790bl5.jpg
http://img155.imageshack.us/my.php?image=img5791qn9.jpg
http://img370.imageshack.us/img370/9313/img5792pr5.jpg

As you have found, canvas is expensive. I know there are better, cheaper and lighter materials, there is information in Dyson's book. You need something that will stretch, to enable you to get a smooth surface as well as to resist knocks and rocks. Most non-fabric plastic sheets or pre-sealed sheeting like tarp lacks flexibility, although you can use tarp as a cheap temporary covering to test the boat before investing in better materials.

- I second that. Think will do the testing with Tarp and then decide on what else to use, or get canvas when the frame works out good.

I have not built one of these boats but I know that the material is not nailed to the frame below the waterline; I believe it is applied in one piece, sewn at the stem to achieve the shape, and secured with a rubbing strip screwed to the gunnels, then heat-shrunk and sealed. That would apply to a wood framed boat of course. You might find Dyson's methods better suited to bamboo which is rather hard and not flat.

- that was wonderful summary.
Certainly the bottom is not nailed, nor the sides. But from the info I have found in most Skin On Frame instructions, staple them to the Gunwale/Gunnel. I personally think we can apply paste to the Gunnel and then nail them along, so it retains the stretch and does not form small cavity.

There is a picture of a skin-over-frame boat in the last post of http://www.boatdesign.net/forums/projects-proposals/challenge-100-boat-12176-7.html, it has a plastic skin but the builder is planning to replace that with nylon fabric with a polyurethane sealant.

I suppose I shouldn't advertise the competition but you have a better chance of getting experienced help on this topic at this specialised kayak forum: http://www.kayakforum.com/

Good luck with your project!

Thank you so much for your time Mr.Ancient_Kayaker

Would some one tell me how to - Seal a nylon fabric with a polyurethane sealant??
And how the canvas is sealed or treated? I have seen so many pictures, but not much text on this.
Please explain what material to use and how to go about it.

cheers
MS

millionswords

11-26-2008, 10:42 AM

rasorinc

11-26-2008, 11:04 AM

build one. https://www.boatdesigns.com/products.asp?dept=185

millionswords

11-27-2008, 01:28 AM

what material are the "car covers" made off?
Thinking if that be a good fabric for the SKIN?

mick_allen

11-27-2008, 04:47 AM

simplest is to follow the complete instructions for one of the wood frame approaches as described in:
http://yostwerks.com/

http://yostwerks.com/WoodSOFMainA.jpg

but look at the aluminum frame methods as well as the inflatables for all kinds of info.

.

millionswords

11-27-2008, 12:23 PM

I have seen this before.
yostwerks.com - it is really helpful.

Please some one give me ideas for the skin, and how to seal the skin.
If to use polyester fabric, what type to use? Just cloth?

ancient kayaker

11-27-2008, 01:34 PM

1) And any suggestions on how long should my Kayak be?
And why should it be so long - if there is any theory!

2) What I try to build would be a recteational Kayak. So what should I bear in mind, (a) Larger Cockpit (b) Stability - should I make the beam (width ) wider? , if then how big?

PS: I would be comfortable with a 6 Feet Kayak. [portability]

Stability is a very difficult thing to quantise in simple terms. Theoretically it increases proportionally with length and as the cube of the waterline beam, but is profoundly influenced by center of gravity. A small boat that rides lower in the water can be more stable than a longer, wider boat.

Primary stability measures resistance to heeling as the boat starts to heel, secondary stability measures resistance to heeling as the gunnels approaches the water. You can have too much stability in some situations; as an illustration, a sea kayak will have less primary stability than a pond boat to allow a big waves to pass underneath without excessive rocking but it will usually have higher secondary stability.

The hull cross-section profile strongly influences the relationship between primary and secondary stability. High primary stability and weak secondary stability is undesirable, even dangerous. Some kayaks are actually designed for low stability to allow rolling.

A 6ft kayak would not be satisfactory even it it supported your weight! Unless you are very short there would be no room for your feet, it would be a dog to paddle, and would probably spin around at the least provocation.

A long narrow boat is generally faster than a short wide one, but a very long boat is harder to push along at low speeds than a shorter one. The long boat will come into it's own when you are working hard. Don't overdo length for speed if you just want an easy paddle!

Most solo kayaks are 12-17 ft long but sea kayaks are often 22+ ft. My shortest kayak is 9.5 ft long with a 30 inch beam; it is very stable and manouverable. However, it is a bit uncomfortable if there are power boats around as the waves cause it to rock rather wildly. About 32 inches is about as wide as a kayak gets.

Canoes are typically wider, 36 inch being typical, but as you sit or kneel higher they need the extra beam. My favorite boat is a wood canoe, 12 ft long with a 25.5 inch beam at the waterline; however I sit in the bottom same as for a kayak so it is a halfway-house kind of boat. It is tippier but it paddles faster with less energy and runs in a dead straight line. The straight running (tracking) is great for bigger lakes where you can just concentrate on the paddling without constantly correctling your course but a nuisance in a winding stream.

In a long boat manouverability can be improved by rocker, which is the amount of curve along the bottom. My wood canoe is dead straight, I am building another similar one with about 2 inches of rocker which should turn easier. Manouverability is also increased by a rounded hull, whereas sharp edges or chines increase tracking.

Cockpit size and shape is a personal thing. I prefer a large cockpit because of my age; it is easier to get in and out. Sea kayakers wear a skirt which seals to the cockpit rim, this is easier with a smaller cockpit.

Referring to Mick's pics in the above link, Nikumi is a Baidarka, very narrow and designed for rolling. It has lots of chines with gentle angles so it approximates to a rounded hull. The Sea Bee is shorter and beamier but still fairly narrow, "designed for good handling in rough water conditions."

Here in Canada cars are covered using tarps (tarpaulins), a stiff, completely waterproof fabric supplied in sheets with reinforced eyelets. I have used this material for sails and others have used it for boat skins, but it's a bit crude looking, rustles a lot and although it is tough it punctures easier than nylon. I notice that PVC is mentioned in the above link.

It is starting to get complicated, isn't it? In Canada most people just buy a rotoformed plastic kayak at the nearest hardware store. That's what I did for my first kayak. I don't know if kayaks are readily available in your country; the "factory" boats are typically twice the weight of wood or canvas boats but are tough and usually well designed, generally with an emphasis on safety. As experience and enthusiasm builds, one starts to look for performance and "something different."

millionswords

11-28-2008, 09:25 AM

hey Ancient_Kayaker,

It ain't getting any complicated at all.
It looks it's getting better day by day as you and other members throw light into the making of a kayak.

:: NO KAYAK IS NOT AVAILABLE READILY :: here in India.
Only a couple of websites import and sell, which are way too damn expensive and are only plastic mould kayaks mostly Sit On Top I have seen.

I think knowing about the theory, understanding the principles and building one slowly, making mistakes and learning makes me more confident on the Boat.

I will take my time to research the theory, and understand what I want, in the kind of waters I would be navigating with your help. Then plunge into building one.

To do that, you guys have to guide me through patiently, understanding that I'm not a boat builder or any expert. So far it has been really overwhelming response, I love the way you guys have slowly stuffed so much knowledge into my head and a lot of confidence.

Availability of material, and research for material is the first step, and when the material is decided, procuring the same and starting work is just a little time away.

Looking forward to more info and tips and a lot of encouragement from you guys.,

now some Doubts:

1. Plywood: - I saw some ply in the morning, go bonkers at my dad's house due to flooding. It was the plywood plank that was laid under a Cot that was ruined so badly I got scared seeing it. [my dad's house is now marooned in hip deep water due to storm and heavy rain lashing the city, a Ford car and a Daewoo Matiz car are fully drowned in the flood water!!!] Wish I had built my Kayk before the floods!! ;)

Would Ply do good on a boat? Some serious doubts started to linger in my mind.

2. Found some very Light wood (looking like cedar) strong and resists water in the same house, that started to float from under some packages. Wonder what wood this was, will find out soon.

3. A kayak certainly has a Sharp Chine, as far I have seen. Are there rounded Chine Kayaks made? I would prefer a good tracking, and navigate in winding canals. What is the type of Chine needed then?

4. Do I need a rocker, if so how much rocker.? How do I achieve in bamboo.??

5. No rapids, No speed, no waves made by other boats, virtually a no-mans-canal!! How stable (or unstable) would my Kayak be when there is a motorboat making waves around? (a rare occurrence, only if i decide to paddle in the boat house).

ancient kayaker

11-28-2008, 12:47 PM

I am very sorry to read about the floods: the awful happening in Mumbai/Bombay has overwhelmed the international news here. I hope that you and your family have not suffered too much from either event.

Plywood for boats is usually marine ply, made to BS1088 which sets standards for the veneers, glue, voids, and resistance to water which are quite stringent. There are other good ply types around, but most ply quality is not adequate for use on the outside of a boat where it is exposed to water for long periods and may delaminate. having said that, if the ply is solid and you paint or varnish it well it would probably be OK for the frames (transverse members) of a skin boat. Such a light boat is usually taken out of the water after use and is not left to soak. Suitable thickness: 1/4 inch bare minimum may need reinforcing, 1/2 inch OK but rather heavy.

If you have Light lumber (solid wood cut to dimensions) that is strong and resists water it is probably suitable. If it seems that the boat will end up significantly lighter than the designer intended, you can increase the thickness of the stringers (longitudinal members) a little. Check to see the behaviour of the wood as it dries out, it should not twist or warp excessively.

ps, don't forget you will need a double-bladed paddle for a kayak

There are kayaks with rounded hulls such as molded boats and cedar strip boats which do not have chines. Skin boat and ply boats have chines. Chine is the nautical term meaning a longitudinal edge under the waterline where 2 planks are joined or the skin passes over a longitudinal frame member or stringer. A hard chine is a sharp corner, a soft chine is rounded off somewhat.

Rocker is just the bottom curvature of the boat viewed from the side. Zero rocker means the bottom is straight. Negative rocker, or a concave curve, is undesirable and is usually a sign of a damaged boat. Tracking and manouverability are compromises and somewhat opposites; for winding canals a long boat with arrow-like tracking would be a problem and manouverability would be more important. Since chines aid tracking, a chine hull for such an application would typically have more rocker to aid manouvering, perhaps 2 inches, compared with a rounded hull that might have less than half that much. However, it's a matter of how the boat "feels" in the water and highly subjective.

The shape of a skin-over-frame boat and its rocker is defined by the shapes of the frames and their spacing. The frames are placed on a strongback to hold them firmly in place during the building process; when the stringers are bent over the frames and fastened they take up the shape of the hull automatically. It is much simpler than it sounds.

Starting with a known design will give you whatever the designer intended in the way of stability; most designers are happy to discuss their designs so don't be afraid to ask. A really unstable boat can be improved with small floats or sponsons along the gunnels.

Being somewhat of a maverick I subscribe to the JGOWI philosophy (Just Get On With It) for matters that do not involve great cost and risk to life; my first 2 boats were my own designs built using door skin ply, a very light but poor quality ply intended for strictly indoor use. The designs were not very good, but it sufficed for the short life I had in mind for these boats, and allowed me to develop my own ideas of design and construction for very little cash. Remember, you can always build another to a different design, with other materials, and learn as you go. Once you have a grasp of the fundamentals, there is not reason why you cannot modify a design to suit your own needs. With a skin-over-frame boat, if the frame is lashed some portions of it can be reused in the next boat.

messabout

11-28-2008, 01:26 PM

For a first time builder of a boat such as the one you describe, I suggest that you give a serious look at the "Six Hour Canoe". This is a design for a dead simple but entirely adequate boat. It is made from Just two sheets of 4" x 8' ply. The boat was contrived several years ago by Mike O'Brien, one of the editors of Wooden Boat Magazine. It has since been used as a project build for numerous youth organizations. As the name implies it can be built (maybe) in six hours. It is that simple. Finish work is quite another matter. That will take considerably more than six hours, depending on how fancy you wish to seal and paint it. It can be built and be ready for launching, paint and all, in a week to ten days. Most of which is time expired while waiting for glue to set and paint to dry.

Though it is called a canoe, it is kayak like, in that one uses a double paddle for propulsion. It is about 15'-6" in length and 28" beam at the sheer line. There is a paperbound book that walks the builder through every detail. The book is cheap, around $15 I think. That brings us to another subject; The paddle. The Six Hour plans include building ones own paddle. Scrap from the ply sheets allow for material. Total cost should be well within your $100 budget. BUT, after a few outings you will realize that a high quality paddle is desirable. A good paddle will cost at least as much as the whole damned boat, and can even run into several hundred dollars..Carbon fibre and all that don't you know. Nevertheless you can get along with the home built paddle that is on the plans, wherin the paddle will cost two or three dollars.

If you want an exotic kayak, then this is not the one. But if you want an entirely adequate kayak for enjoying liesurely trips on those canals then this is a good bet.

P.S. The manner, in which you write, suggests that you may be a westerner. The events at hotels in the last few days cause many of us to be concerned for new found friends in India. We have had our tragic lessons here in the US and, despite what the crazies think, we do care for people elsewhere.

millionswords

11-28-2008, 10:10 PM

P.S. The manner, in which you write, suggests that you may be a westerner. The events at hotels in the last few days cause many of us to be concerned for new found friends in India. We have had our tragic lessons here in the US and, despite what the crazies think, we do care for people elsewhere.

I feel Sorry - Ashamed - Helpless for the act of the terrorists, who seemed to have infiltrated through the waters into south Mumbai, lucky that I was not in Mumbai/Bombay during these attacks, far away some 1500KMs south of Mumbai, but caught in the flood here.!!

It is a security lapse, certainly they have managed to find foreign(US, Israelis and UK) tourists and nail them down. Seems to have been an extended attack of these citizens on less secure or unexpected land! Guess no one can anticipate such attacks and make security measures?

Wonder where this is all leading to? Fear grips!

Flooding:
Reserve Police, Firemen and the Army men have come to rescue people who were flooded. Attached are some photographs of the assembling of the Inflatables.

millionswords

11-29-2008, 01:17 AM

Some Sat images from Wikimapia of the canals - to understand the layout.

ancient kayaker

11-29-2008, 01:28 PM

I don't want to highjack this thread for a discussion on terrorism, but while they seem to have targeted foreign tourists, the number of people reported as killed far exceeds the deaths of Israelis, Americans and other westerners. As always, it is the unfortunate standers-by who suffer most in these indiscriminate acts of hatred.

millionswords

11-30-2008, 07:18 AM

Collateral Damage - do we call it?

The targets to how far my brain can think were:

1. Well Off Indians,
2. Israelis
3. Americans and
4. English

They have asked for passport, and IDs before killing.
They have kept people standing (17 of them) in a line and made a call to someone and asked if they can proceed with the killing(massacre) and executed it.

1. Cafe Leopold is a cafe where the average Indian walks by watching the 3 dozen tables fill with Whites, it was not a place for the common man. Leopold was the first target of shooting early during the attack.

2. Taj was not for the common man, Taj Palace was occupied by the worlds biggest money makers and decision makers. Wonder how many of them have lost life, only to wait and see the list come out with some identification in a few days.

I read, a bank chairman was stopped and asked who he was, and what he does for a living - he replied he was a teacher from bangalore and the terrorist asked him "how a teacher could afford to be at the taj Palace?" and prepared to shoot when a grenade exploded near them and the man escaped to tell the story!

Damn - scary.
Still to see what news comes out and how the plot unfolded.

National Security Guards came to the scene after 9.30 hours! - Dhud! shame.
Operation was over when the last man standing was taken by them and to find no hostages were left alive, and every floor has dead bodies and still counting!

I hate to see the TV now!

PS: Me too don't want to hijack this thread - may be we should discuss these in the open forum. (though this event has some relation to boats we don't want it to be in the boat discussion area!!) - I couldn't help replying. Lets drop it here and continue with the boat building.

Will find some more info on material soon, once the flood recedes and get back to you guys.

bye,
MS

ancient kayaker

11-30-2008, 04:53 PM

My dear MS: I have no words for this, but others might want to read and respond to your news. The news on the topic here is very trite and parochial, we do not get the full picture until days later if at all. I suggest you repost your information in the Post Tsunami forum, which is probably the most appropriate; it is at:

http://www.boatdesign.net/forums/post-tsunami/

I for one will be looking for it.

-AK

millionswords

12-01-2008, 02:47 AM

For a first time builder of a boat such as the one you describe, I suggest that you give a serious look at the "Six Hour Canoe". This is a design for a dead simple but entirely adequate boat. It is made from Just two sheets of 4" x 8' ply. The boat was contrived several years ago by Mike O'Brien, one of the editors of Wooden Boat Magazine. It has since been used as a project build for numerous youth organizations. As the name implies it can be built (maybe) in six hours. It is that simple. Finish work is quite another matter. That will take considerably more than six hours, depending on how fancy you wish to seal and paint it. It can be built and be ready for launching, paint and all, in a week to ten days. Most of which is time expired while waiting for glue to set and paint to dry.

- thanks for the suggestion, wold have a look.

Though it is called a canoe, it is kayak like, in that one uses a double paddle for propulsion. It is about 15'-6" in length and 28" beam at the sheer line. There is a paperbound book that walks the builder through every detail. The book is cheap, around $15 I think. That brings us to another subject; The paddle. The Six Hour plans include building ones own paddle. Scrap from the ply sheets allow for material. Total cost should be well within your $100 budget. BUT, after a few outings you will realize that a high quality paddle is desirable. A good paddle will cost at least as much as the whole damned boat, and can even run into several hundred dollars..Carbon fibre and all that don't you know. Nevertheless you can get along with the home built paddle that is on the plans, wherin the paddle will cost two or three dollars.

- Let me build the Kayak First, then will look for the Paddle.! I think I can procure some fiber paddle if it gets complicated.

If you want an exotic kayak, then this is not the one. But if you want an entirely adequate kayak for enjoying liesurely trips on those canals then this is a good bet.

- I certainly do not want an exotic kayak, would love to build one in the due course.

millionswords

12-01-2008, 02:50 AM

ancient kayaker

12-01-2008, 03:37 PM

I found some information at http://www.guillemot-kayaks.com/Building/ExprncBldgngBaidarka.html#RTFToC8

It has details on how to attach the skin; here it is 15 oz nylon and hypalon is also mentioned. Here's another that mentions cotton duck sealed with paint: http://www.qsl.net/wa1urb/98.html

If you google skin & kayaks you will get lots of sites.

As a ps, when wondering which materials are suitable, remember that the Inuit people who developed these fascinating craft over hundreds of years used whatever came to hand, mostly the skin of seals and wood washed up by the sea.

millionswords

12-02-2008, 03:41 AM

Yes AK,

Inuit Kayaks and their techniques are a very strong driving force for me to re-invent the kayak and the simple things to use. Rather buying a fancy Kayak for $1000

I plan to go some 100 KMs south of Chennai/Madras to a place called Marakkanam which is said to be the Boat Builder's village. I think I can get some idea and some simple techniques to learn from them. Should spend some time and watch them work.

Will update with pictures when I do the above.
Here is a picture of a simple improvised "Kattu Maram" which in Tamil Language means "Tied Wood" which also serves as the origin of the word "Catamaran" aquired by the English during their rule over India.

millionswords

12-02-2008, 05:08 AM

some interesting shots from Kerala's backwaters. "House Boats"

http://farm1.static.flickr.com/144/370771314_0d8beb1fea_o.jpg
http://farm4.static.flickr.com/3127/2675908471_4b484ed01e.jpg?v=0
http://farm4.static.flickr.com/3288/2378981437_6f90f28d12.jpg?v=0
http://farm4.static.flickr.com/3136/2552566183_e84046f7ba.jpg?v=0
http://farm3.static.flickr.com/2022/2014486395_50bfb87362.jpg?v=0
http://www.flickr.com/photos/miffymoo2/2239162039/

ancient kayaker

12-02-2008, 12:28 PM

Some lovely shots there; the canoe is alive and well and living in India! Some of the scenes are the kinds of places I would like to visit by boat; they made my paddling arm itch!

I particularly liked the "Indian-ness" of the houseboats, if I may say that without appearing patronising in any way. They are so utterly unlike the prosaic houseboats I am used to. It would be fun to tie up one of those alongside the waterside general store on my favourite lake and watch the reaction of the other boaters.

It looked like the wicker roof had been built separately on land and was being hauled onto its intended hull. Would that have been custom-built by a specialist or is that just normal practise? I would have assumed the roof would be built onto the hull after launching.

The "Kattu Maram" has beautiful lines. It reminds me strongly of the wood dugout canoes formerly made on the West Coast of canada by the Haida and other indigenous people. Some were very large indeed and works of art as well as seaworthy craft. The Canadian canoe museum is only a 2 hour drive from my home. On my last visit I met the new general manager, John Summers, who showed a friend and me around the Collection Center, which is separate from the public areas of the museum. It is a vast building with an awesome collection of 600 boats of all descriptions, wood and birchbark canoes, kayaks, dugouts, war canoes; mind-boggling. What the mind and hands of man can do with simple resources and tools!

Here are some links to boat museum sites:- http://groups.msn.com/woodenboatbuilder/yourwebpage1.msnw
The canadian canoe museum is at:- http://www.canoemuseum.net/default.asp

millionswords

12-02-2008, 01:08 PM

AK,

the Kaattumaram has always raised doubts in me from my childhood.
Always!
When I'm at the beach with my family, I used to wonder how this piece of log keeps the men safe! When huge boats sink and I have read stories, how these men put trust on a few logs! that look so skeptic!

Still I look amazed when I watch the fishermen venture into the sea with the Kattumaram and how they jump on to it after there is a big wave to take them in!

The Kettuvallam(hbouse boat) is unique to the Kerala part of India.
Kerala is a very very small state in India, but has the most number of backwaters and river canals. Though these boats are purely tourist now, used to be carriers of Rice and other merchandise early days.

They build the roof part on the hull sometimes on land, sometimes after the launch. I have seen both types. They improvise on it, as the requirements arise. The tourists [mostly foreigners] stay on these boats, for days together sometimes, locals cook for them on the boat, they catch fresh fish and cook as they like. The scenery is breathtaking, sunrise and sunsets are magical, and the best part is, where you can reach in these boats - roads cannot!!

The actual Kattumaram looks like this:

http://www.uwa-pro.de/projekte/bilder/05-s.jpg
http://www.flickr.com/photos/nikithecreator/3008844433/
http://www.kodimunai.com/images/kodi_kattumaram.jpg
http://farm3.static.flickr.com/2044/1574563943_28f00b13ed.jpg?v=0
http://www.flickr.com/photos/oochappan/370660704/

millionswords

12-03-2008, 08:03 AM

Bamboo:

there are two types of them, one the hollow and then the solid[not solid really, thick walls]. Managing to get same diameter sticks are a big deal. The bamboo tree grows big on the bottom and narrower on the top. Wonder how these guys at the furniture making find the right stick.

Once I find out how the bamboo sticks are chosen, I can go ahead and procure some. Have to visit the furniture makers once again.

ancient kayaker

12-03-2008, 11:19 AM

Is anyone trying to save these marvellous craft? I noted that they are made from several logs, not from a single log as I had assumed, though some may be. In most, the wall thickness looks greater than the dugouts of the Canadian West coast.

Dugout canoes were built by the Salish, Haida, Tlingit and other peoples of the West. Some of those boats are still being built today, but only as projects, not for their original purposes. The boats were carved from a single tree trunk, and many had lovely lines and amazingly thin walls. The outside was carved first, then small holes were drilled to a predetermined depth so the carver would know when to stop cutting out the inside. The boat was still narrower than desired at this stage, limited by the size of the tree. It was filled with water which was then heated with hot stones. The hot water penetrated and softened the wood while the weight of the water forced the boat to open; this was a tricky operation requiring as much experience as the carving. Once it was wide enough it was braced with thwarts and allowed to dry, although not fully as it would tend to split. Decorative carving and painting was then added to complete the boat. The bows and sterns were particularly heavily decorated and a platform sometimes added for observation, fishing or fighting. The first link belongs an organization started by Al Lubkowski, an old friend of mine who moved to Vancouver Island a long time ago; I haven't seen him for many years (he's "the captain"); his big canoe was built from strips rather than a single log; it is now very difficult to get logs of the size required, also the dugouts are heavy, hard to store and rather delicate.

http://www.blackfishwilderness.com/bwho1.htm
http://www.joejack.com/coastsalishhistory.html
http://oceanexplorer.noaa.gov/projects/02tribal/canoe_tech/canoe_tech.html

ancient kayaker

12-03-2008, 11:41 AM

I would not think the varying diameter of the bamboo poles along their length, and the difference from one to another should discourage you from building your first boat. The thickest pieces would be needed for the gunnels and keel which determine hull strength and stiffness. On the gunnels, I would place the largest diameter at the bow, and would ensure strength in the cockpit coaming which is stressed by the paddler's weight during entry and exit. If a uniform diameter pole of sufficient size is not available for use as a keel, then you can arrange the thickest part of the keel under the cockpit and lash two lengths together so the keel tapers towards the stems. A series of shorter, thinner poles at the bottom of the cockpit would distribute the paddlers weight. Long, thin bamboo poles would be excellent as stringers to define the hull shape, a somewhat thicker one to hold up the fabric decks (the kingplank).

Afterthought: you can probably join bamboo poles more neatly than lashing, if you hollow out the ends (internode) to accept a strong dowel and use epoxy.

millionswords

12-03-2008, 12:24 PM

AK,

My idea of making this Kayak was to go around and do some photography where we can't reach by road. So I need to carry minimal photography equipment in this boat, where would I store them in the Skin-On-Frame types? Will there be a hatch to keep stuff, and reach it while on water? what is your thoughts?

PS: see some of my photographs here (http://www.flickr.com/photos/tamil/).

millionswords

12-03-2008, 12:28 PM

Afterthought: you can probably join bamboo poles more neatly than lashing, if you hollow out the ends (internode) to accept a strong dowel and use epoxy.

on the afterthought: I have never seen this happen. The idea seems it might work, dunno if there are any practical difficulties., should check.

Hollowing out the nodes and joining them with Epoxy [Fevicol] should work. But where would I need it in this project at all? Really can't envisage!

Something just like what we plan above right?
Only difference is, I plan it with Bamboo. If I have to choose something close to the willow shown in these pictures below, I think a banyan root would suit.
The banyan root can be twisted and rolled into a circle to form the frames. Dunno how strong/brittle they can be. Bamboo can be made into rings of desired shape.

http://www.shelter-systems.com/gripclips/kayakassem.html

aah, I found a bamboo frame! kayak

http://bp2.blogger.com/_yFfmvdFuhnI/SCdu0eiAK3I/AAAAAAAABWM/PWHnI89kZLc/s1600-h/PR+Kayak+Frame.jpg
http://antarcticiana.blogspot.com/2008/06/bamboo-kayak-attack.html

http://outdoors.webshots.com/photo/2435351560101066046hcTxLN
http://bp2.blogger.com/_yFfmvdFuhnI/SCdu0eiAK4I/AAAAAAAABWU/iUTOJMlBx_0/s1600-h/Stowage+Below.JPG

ancient kayaker

12-03-2008, 02:46 PM

The boat in the 3rd link was very nice. The ribs look like they were steamed to shape, and the slats for the floor have been split. Notice the way spacer blocks have been used occasionally between a rib and a stringer to avoid over-twisting the stringer. If you are comfortable with those techniques it would hard to imagine a nicer boat. I initially thought that ply frames would be easier than the ribs; you may still require ply forms to help shape the ribs. I know nothing about banyan root, not much of that in Canada! However, whatever you have for the ribs must hold its shape rigidly. Here, thin oak strips are often used, once steamed they become very easy to bend and after they dry out they become stiff and strong again and hold their shape. Ply is easy to cut but not so strong so it has to be deeper, but it is very easy to do. The stringers of skin on frame boats are often screwed to the frames, but the boat in the third link has lashings; if you go that route, take note of how the lashings are done, as that is the correct way. Some people cross over the cord which is incorect.

If ou can get bamboo in sufficient lengths that are fairly uniform in diameter then you do not need to join them, but if they taper excessively you could join 2 poles at their thickest parts, so long as these joints are staggered.

A hatch might be more difficult to make in a skin boat, a pouch with a zip might be easier, but I've not seen either. I often carry a camera with me in a kayak; I don't find the hatches much use for anything that you would want to reach while in the water, although they are fine for stuff that you need once on land, such as camping supplies. I carry a camera in a plastic Ziploc bag usually; it tucks inside the mesh pocket of my floatation vest. I don't know if those bags are available in India though. I also have a screw-top plastic jar that once held a set of emergency equipment (whistle, throw cord, inflatable float-bag etc.) that my smallest camera fits into. Elastic cords on the deck are very useful.

Speaking of floatation vests, I never, ever go out in a boat without one. I have never needed it but it simply isn't worth the risk. I swim like a fish, stay afloat for hours, and can even sleep in the water, but I still take care.

millionswords

12-04-2008, 02:05 AM

Certainly not looking to make a poor boat.

The boat in the 3rd link was very nice. The ribs look like they were steamed to shape,

- here a flame-gun is used. Flames are directed on the bamboo and wiped as often with wet cloth. Once this is done, bend it, and wipe it again. It stays in that shape without any more force or effort. No clamps, no strings either.

and the slats for the floor have been split.

- I wonder why. A thick bamboo bark can be used here, once portion of it.

Notice the way spacer blocks have been used occasionally between a rib and a stringer to avoid over-twisting the stringer.

- The ribs look like have been made by "split barks of the bamboo", instead I would think it is better to use the whole solid parts of the taller part of the bamboo. [refer my picture in page 2, of a furniture.]

If you are comfortable with those techniques it would hard to imagine a nicer boat.

- Comfortable, is a relative question. Compared to wood work, like sawing, screwing, need for right blades and tools, I guess employing the bamboo and lashing and the flame-gun is easier for the first project.

But again, I dont want to land up with a poorly made one like [this one (http://bp3.blogger.com/_yFfmvdFuhnI/SCduzuiAK0I/AAAAAAAABV0/knzHy3YVxR4/s1600-h/Gunnels+Awash.jpg)]

http://bp3.blogger.com/_yFfmvdFuhnI/SCduzuiAK0I/AAAAAAAABV0/knzHy3YVxR4/s1600-h/Gunnels+Awash.jpg

I initially thought that ply frames would be easier than the ribs; you may still require ply forms to help shape the ribs.

- Ply frames are an option. But I dunno how to work with them, nor have the tools. Really dunno what tools I require either, gluing them and the use of so many many clamps. Haven't seen a single such clamp here, all my 30 years of life.

I know nothing about banyan root, not much of that in Canada! However, whatever you have for the ribs must hold its shape rigidly. Here, thin oak strips are often used, once steamed they become very easy to bend and after they dry out they become stiff and strong again and hold their shape.

- Just a thought (banyan). Should check how it will suit, will talk to some carpenters and gardeners to know about the banyan root.

Ply is easy to cut but not so strong so it has to be deeper, but it is very easy to do. The stringers of skin on frame boats are often screwed to the frames, but the boat in the third link has lashings; if you go that route, take note of how the lashings are done, as that is the correct way. Some people cross over the cord which is incorect.

- How do u define correct and incorrect?
- lashings are done with bamboo strips, soaked in water, and then wiped with glue. It holds good. Real good.

If ou can get bamboo in sufficient lengths that are fairly uniform in diameter then you do not need to join them, but if they taper excessively you could join 2 poles at their thickest parts, so long as these joints are staggered.

- I have seen same length bamboo often. Should find where to procure them from. Will let you know in a couple of days.

A hatch might be more difficult to make in a skin boat, a pouch with a zip might be easier, but I've not seen either. I often carry a camera with me in a kayak; I don't find the hatches much use for anything that you would want to reach while in the water, although they are fine for stuff that you need once on land, such as camping supplies. I carry a camera in a plastic Ziploc bag usually; it tucks inside the mesh pocket of my floatation vest. I don't know if those bags are available in India though. I also have a screw-top plastic jar that once held a set of emergency equipment (whistle, throw cord, inflatable float-bag etc.) that my smallest camera fits into. Elastic cords on the deck are very useful.

- Mine is a not so little, prosumer camera. Ziplocks are available, and a jar is a good idea - I can get one of those TUPPERWARE tight seal jars to hold some stuff inside.

- Life-Vests yeah, we can get them here. But that will be the most expensive gear I guess, next to the paddle.

Speaking of floatation vests, I never, ever go out in a boat without one. I have never needed it but it simply isn't worth the risk. I swim like a fish, stay afloat for hours, and can even sleep in the water, but I still take care.

- True. i swim good too, I can float and sleep. Better get a vest once I get on water.

millionswords

12-04-2008, 02:39 AM

PU, PVC, Synthetic Leather - are available in plenty and easy to procure. Fairy cheap. It can be riveted/stitched perfectly. Would these be good for the skin?

These are used on bags, handbags, duffel-type bags, some footwear, seat covers, and sometimes table cloth. Its soft on top, looks like fake leather, it can stretch, has a diamond shape cloth(cotton) reinforcement below. Can be cut with a pair of scissors, can be sewed together, can be pasted, and riveted either. There are other types which come in various thickness ranging from 0.5mm to 1.5mm, and some times nylon feel fabrics are made too.

Some pictures Under:

millionswords

12-05-2008, 04:48 AM

Bending Bamboo:

AK, here is a video that explains every step of bending a bamboo to a desired shape.

http://video.google.com/videoplay?docid=-7914646950791304015

same trick, using a mould - suits best for making our ribs.

http://www.bamboocraft.net/forums/showthread.php?t=1489

ancient kayaker

12-05-2008, 12:46 PM

For cutting out ply frames all you would need is a jigsaw and a drill.

The correct method of lashing is what I have read. The bamboo strips sound like a good idea, as they dried they would probably shrink.

For the skin material I have no actual experience, I can only recommend doing what I would do and research the Internet. If several sources say something is good, it probably is. Skins can last for decades but may need to be changed if badly damaged. Also you can change it if it doesn't work. A very stiff fabric would be hard to apply without wrinkles, a very flexible fabric would bulge inwards under water pressure. I imagine the best thing would be a moderately stretchy woven fabric that could be heat-shrunk to get out the wrinkles and tighten it after application, then sealed with a suitable paint.

Nice video on bending bamboo. The sand is an old trick used by plumbers to bend pipes. I didn't know the internodals could just be knocked out. I note that the process uses dry heat to form the bend, I am not sure whether the cold water simply cools it or if moisture is needed to maintain the bend. The moisture probably helps to prevent the bamboo drying out too much and becoming brittle. I suspect a lot of skill and experience is used that is not apparent. On a personal note, I enjoyed the chickens in the background, my parents kept several, it reminded me of when I was very young.

I wonder if steaming will work on bamboo; most woods can be steamed, a large diameter tube and a kettle are all that is needed. It has the advantage that the wood is brought to a uniform temperature and many pieces can be prepared in one batch for bending, which would save time for a large number of parts. I'm not sure how bamboo would react to the humidity or if the temperature of the steam would be high enough. An oven would be another way to get temperature control for small parts. There are also electric hot air blowers used for shrinking plastic tubing or stripping paint, which might be easier and less risky than an open flame.

On the matter of clamps, you could use bindings instead, by first drilling holes through the forms for the cord to pass through. I use up to 100 clamps for gluing gunnels to the ply sides of my boats, but I make them not buy them. For small clamps, you can cut a slit along the length of a piece of PVC pipe and then saw it into lengths, about 3/4 to 1 inch long works for me. For a few dollars I get dozens of spring clamps. I have a few proper clamps which are easier to use single-handed for the initial attachment.

millionswords

12-06-2008, 01:14 AM

AK - On a personal note, I enjoyed the chickens in the background, my parents kept several, it reminded me of when I was very young.

he hehe - I like them Chickens too, they make a wonderful combination with small puppies around, making the atmosphere very light!! Interesting that you noticed them too, I did.!! I missed to see the bending sometimes and went back to rewind the video!!

For cutting out ply frames all you would need is a jigsaw and a drill.

is the jigsaw same as the HackSaw?

The correct method of lashing is what I have read. The bamboo strips sound like a good idea, as they dried they would probably shrink.

Nansen's Kayak was not made of any bamboo strips, wonder why. I prefer the full stick than the strips, because the strips are prone to breakage and rupture.
Nansen's ribs were not made from bent bamboo!
http://bp1.blogger.com/_yFfmvdFuhnI/SCdubOiAKxI/AAAAAAAABVc/EwNkpeeJOCY/s400/Bamboo+Interior.JPG

He has made the ribs from Lashing, and small strips to reinforce the lashings. Just lashings - wow!
Should try to make a rib, and test if I can get a hang of the trick. If it works, nothing like it!
The bamboo used is a very small dia culm. It looks like 3/4 to 1 inch diameter.
I can get 15 feet sticks, 10 numbers for less than $6, that is like 150 feet of Bamboo sticks, off which I can throw away some 20 feet and use the rest.

For the skin material I have no actual experience, I can only recommend doing what I would do and research the Internet. If several sources say something is good, it probably is. Skins can last for decades but may need to be changed if badly damaged. Also you can change it if it doesn't work. A very stiff fabric would be hard to apply without wrinkles, a very flexible fabric would bulge inwards under water pressure. I imagine the best thing would be a moderately stretchy woven fabric that could be heat-shrunk to get out the wrinkles and tighten it after application, then sealed with a suitable paint.

Guess this will be a trial and error run, and will be the most expensive part. Though affordable for the right output. Will start to see and feel some materials in a while.

Nice video on bending bamboo. The sand is an old trick used by plumbers to bend pipes.

Hmmm

I didn't know the internodals could just be knocked out.

Yeah they are brittle like thin cookies. Just pressing by a finger can knock it off. Differs with the size of the culm.

I note that the process uses dry heat to form the bend, I am not sure whether the cold water simply cools it or if moisture is needed to maintain the bend. The moisture probably helps to prevent the bamboo drying out too much and becoming brittle.

The water first cools down the temperature, it retains the bend, it prevents burning of the skin of the bamboo over prolonged exposure to direct heat.

I suspect a lot of skill and experience is used that is not apparent.

Sure does, it is a very patient method.

I wonder if steaming will work on bamboo; most woods can be steamed, a large diameter tube and a kettle are all that is needed. It has the advantage that the wood is brought to a uniform temperature and many pieces can be prepared in one batch for bending, which would save time for a large number of parts. I'm not sure how bamboo would react to the humidity or if the temperature of the steam would be high enough. An oven would be another way to get temperature control for small parts. There are also electric hot air blowers used for shrinking plastic tubing or stripping paint, which might be easier and less risky than an open flame.

Steaming might be easier and much simpler and cost effective and safer like u said. Industrial propane cylinders and guns are hard to procure, under a budget. Though I can rent them for a few days.

For steaming, I just need a GI Pipe [thick alloy metal] with a bigger diameter, say about 4 to 5 inches, and a kettle, which I can make easily. Wonder if bamboo reacts to steaming, and allows bending. The bending is needed particularly for the ribs only. Rest are not a big bend, and can be achieved by manual dry bending.

On the matter of clamps, you could use bindings instead, by first drilling holes through the forms for the cord to pass through. I use up to 100 clamps for gluing gunnels to the ply sides of my boats, but I make them not buy them. For small clamps, you can cut a slit along the length of a piece of PVC pipe and then saw it into lengths, about 3/4 to 1 inch long works for me. For a few dollars I get dozens of spring clamps. I have a few proper clamps which are easier to use single-handed for the initial attachment.

I saw your picture of the PVC clamps, guess that would be easy to make and cheap. Will buy some actual clamps if i start to work with wood.

AK, have a look at this picture, open large.
http://www.boatdesign.net/forums/attachment.php?attachmentid=27408&stc=1&d=1228547969

Second Image below:

Wonder how the Nansen's ribs hold the shape? with just lashings?

ancient kayaker

12-06-2008, 12:36 PM

In the picture of the kayak with the bent ribs, the front edge of the cockpit is a single piece of wood that has been sawn to shape; you can see the grain running straight across.

Although the ribs and cockpit floor of that kayak are bamboo the longitudinal members, stringers, keel and gunnels, are regular wood (lumber) but could be replaced with whole bamboo. The rib to gunnel joint uses a rabbet which requires some carpentry skill, but if you use the Nansen type ribs you would not need that as they are lashed.

The Nansen ribs can distort if the lashings are not very tight indeed, note that several of them have cross ties to prevent them distorting; you can see this in the picture. The trick is to create a series of triangles using cord to stabilize each of the angles.

A jigsaw is a handheld electric power tool, see: -

http://en.wikipedia.org/wiki/Jig_saw

If you don't have access to a jigsaw, a small handsaw with a sharp, fine-toothed narrow blade should do the job. Coping saws and fretsaws are commonly used for fine work cutting ply, but the frame will interfere with the cut on large frames so a saw with an unsupported blade would be better.

ps: thanks for the e-mailed picture: nice upholstery, done by the wife I would guess!

millionswords

12-06-2008, 01:02 PM

ps: thanks for the e-mailed picture: nice upholstery, done by the wife I would guess! - sure thing!

what decides the weight a Kayak can hold?
I weigh about 100 Kilos, and 5.10feet.

AK, You said you have no personal opinion on skins, but let me put it on the thread, and see if some one else would come with some answer.

1. Why should the skin be tight? without wrinkles - apart from looking good.
2. I have read many suggest, polyester cloth as a skin, would it not leak? How much will the paint coating help?
3. After painting, do people iron the skin?
4. I have seen some video on stitching the skin, and it seems to be a very very patient work, and procedural, does the stitch need to be very accurate to keep the boat water tight? or is it just for making it looking good?

ancient kayaker

12-06-2008, 05:59 PM

I am an inch taller and 15% lighter; my canoe is 12 ft x 25" waterline beam. My paddling friend is your weight and 6-5 tall, he was OK in it but found it a little too small.

A boat a little larger should suit you. The choice between long and thin or short and beamy depends on your kind of paddling as mentioned before; a short boat will manage lots of turns easier than a 22 ft sea kayak! Boats with rounded hulls or lots of gentle chines turn easier than boats with a few hard chines which tend to cut into the water and cause turbulence when turning sharply. Make sure there is plenty of room for your feet!

This is probably the wrong forum for help on kayaks, at times I feel lonely! We are almost the only ones posting. So I wouldn't wait for more inputs on the skin. You could Google "skin on frame kayaks" which should get some leads, and then follow the links.

I believe heat shrinking is performed before painting; ironing might damage the paint. Loose skin will sag due to water pressure causing drag which will slow the boat. There is a sealant called Hypalon but I don't know much about it; I think it is used to seal nylon fabric; paint is used with canvas but I've heard canvas is expensive. A cheap plastic skin such as tarp would serve to try out the boat in the water before investing in better quality stuff.

I haven't heard of needing a lot of stitching skin since we stopped using sealskin; a stretchy skin material should cover the smoothly boat in one piece from gunnel to gunnel, and could be tightened by threads running on top of the gunnels. It may need to be slit at the stems (bow and stern edges) and sewn, with a sealant applied. I suspect most people just overlap the layers, tack it and apply sealant. I have read that it is tacked at the gunnels and a wood rubbing strip added over the tacks. Bamboo may be hard to tack, you could check that.

A strip of wood attached as a keel from bow to stern would provide protection against sliding over submerged logs, a common experience in my area, and would discuise the sewn and sealed areas at bow and stern.

millionswords

12-12-2008, 04:05 AM

AK,

what is the use of epoxy, and in my case, what would be the use really? would i need it at any stage at all?

1. Should i coat the lashings with epoxy?
2. Should I coat the skin with epoxy?

I get Araldite Epoxy Adhesive, which comes in 2 tubes or two 1 liter containers. Mixing them we get a glue that can be applied on surfaces, which is water proof, resistant proof, and heat proof. I read about Araldite on Wikipedia.

ancient kayaker

12-12-2008, 11:36 AM

Araldite is an epoxy which has been around for a long time. It is very strong, as all epoxies are, but there are different epoxy formulations. I have a lot of respect for Araldite as I used it for many years in the UK but I don't know if it has all the features necessary to make a good marine glue.

Special marine epoxies are used in boat construction. Even marine epoxies vary; some are formulated for gluing wood with a degree of flexibility to match the flexibility of the wood, and to hold when the wood gets wet. Others are formulated for use with glass fiber and yet others used for coating wood.

You should also note that the "five minute" epoxies are often not an epoxy at all, most of them use an entirely different type of resin. These, and also Araldite are very thick so may not penetrate into the wood grain well.

"Should I coat the lashings with epoxy?" I wouldn't reccommend it. It would make the lashings very rigid so any flexing could result in breakage of the lashing or the bamboo. If nylon lashings are used the epoxy may not adhere to the nylon and could flake off when the boat is flexed. The stiffness of a skin on frame boat comes from the skin not the frame. A small amount of glue on the knot might be a good idea though.

"Should I coat the skin with epoxy?" Absolutely not! The skin and the frame work together as an integral whole with the frame in compression and the skin in tension. If you epoxy the skin it may become so stiff that it is in compression when the boat flexes; it is far too thin to support compression loads so it will buckle. even if it doesn't crack it will develop wrinkles that will look ugly and slow the boat.

Based on my limited knowledge I would think the main application for epoxy would be if you wished to use solid wood frames instead of using steam bent bamboo ribs or one-piece plywood frames. Other than that, and possibly in the contruction of the coaming, there is really no much need for an adhesive in a boat of this kind.

The Inuit (Eskimos) that perfected the art of kayak building only had driftwood and bone for the frame, animal tendons for the lashings and seal or walrus skin for the covering. These boats did not last long in use, but with materials such as bamboo, man-made thread and fabric, and a good paint or sealant skin on frame boats become very durable.

Having said all that, I reiterate that I have never built or even owned a skin on frame boat; what I have said is based on engineering knowledge and intuition. So, while I am delighted to provide advice I must be careful not to mislead you inadvertently. The best way for you to proceed now would be to obtain a book, consult with a skin on frame designer of builder, or troll the Net for as much information as you can find on the subject.

millionswords

12-12-2008, 02:50 PM

ancient kayaker

12-12-2008, 05:32 PM

Good luck and good sailing, or paddling that is!

millionswords

12-14-2008, 07:50 AM

AK,

Do i need to follow an Offset Table, and plot it and make a lofting at all?
What dimensions and numbers should I follow if else?

What is the height of the Boat,
what is the interval between the ribs,
what is the curve/rocker to achieve?

Should I consider them at all? Or do I trust my eyes and instinct and proceed?

Where is the need for my station and strongback?
Do I need a strong back - which of them do I mount first 0 Gunnel or ribs or keelson?

Am I asking the right questions?
Or am I worried too much instead of jumping into building them?

MS

ancient kayaker

12-14-2008, 07:19 PM

Your questions reveal that you have not yet decided to design it yourself, adapt a design meant for a different construction method or build to an existing plan for a skin-on-frame boat. Let's look at the options and see the implications.

How you go about it is your choice.

Option 1. If you are willing to do as I did and make several unsuccessful boats to gain experience by all means design it yourself, but there is a lot to learn. Although free software is available on the Internet which will help you develop the general shape of the boat it will not help you with the construction details or guarantee that the boat will be stable and perform well unless you know how to interpret the values given by the analytical features of the software. Questions about the height of the boat, rib or frame spacing, beam, and rocker are related to boat design. Given the experience of designing a few boats, or years of study of boat design, it is no doubt possible to design a boat that will meet it's objectives first time. In practice, it takes lots of practice to get it right.

Option 2. At the other extreme if you build to a plan for a skin-on-frame boat you will have dimensions for all the components such as the frames and the frame to frame spacing, constructional information such as the strongback, material specifications etc.

Option 3. In between, if you have a plan for a boat of a different construction, or just an offset table, then you have the shape of the boat and must decide how to build it. If you have an Offset Table, you will have to determine frame location, which will probably be at the same location as the stations in the table, and you will have to plot the outline of each frame onto your ply or other material and cut it. If you use bent bamboo frames you will still have to make forms around which to bend them.

Should you trust your eyes and instinct? I did that and went for option 1. The first boat had a Vee-shaped bottom, was lovely to look at but flipped me into the water unless I lay flat in the bottom. I ripped out the Vee bottom, increased its beam, and installed a flat bottom. A bit better, I was able to sit up in it but it was still unstable and I only dared try it in my swimming pool. I sawed off the last 2 feet and installed a transom to remove buoyancy and make the stern sink an inch or two, lowering the center of gravity. At this point it was good enough to take to the lake but I had to stay in shallow water. I built another, also with a flat bottom, incorporating what I had learned, but it was little better although much easier to build. After a bit more thought I decided that the flat bottom was the problem. Flat bottomed boats float high in the water and usually have a lot of beam for stability, mine did not and I did not want to built a "fat boat." Up to this point all my boats except the very first one had three planks, two sides and the bottom. I used very cheap materials for these boats.

The next boat had five planks: two sides or sheerplanks and the bottom plank, which were connected by two planks called garboards. The cross section was five sided. Success! This shape resulted in less buoyancy than a flat bottomed boat so the boat sat lower in the water when loaded. Lowering the center of gravity by only 2 inches made all the difference; in such tiny boats stability is on a razors edge. This boat is much lighter and faster than plastic boats and effortless to paddle; slightly tippy but I feel safe enough to tackle a modest-sized lake on a windy day with power boats zipping around. I would not take it out to sea! It's only shortcoming is, it is not easy to turn around, but that is not generally a problem. I used marine ply and other quality materials for this boat, and it attracts compliments and interest. The first 2 boats were scrapped, but I have a good boat after three years of work, several hundreds of hours work and about twice as much money as it would have cost if I had built it to a plan, which would only have taken 60 or so hours. Sounds like a poor bargain, but I loved doing the work and I understand so much more about boats now.

I was in it to learn. I already had boats, and I enjoyed the learning experience of both designing and building; I ended up with a great boat and the ability to produce more if I wish (I have a second one under construction). If you want a reasonable boat for a reasonably low cost in a reasonable amount of time which the certainty that it will turn out well, buying plans for the specific boat and construction method is the best way to go (option 2), the plans will be a fraction of the overall cost and you will have the confidence to invest in good quality material at the outset.

The strong back is needed to keep everything in place and lined up until the boat is strong enough to hold its shape. It will ensure that your boat turns out properly shaped and true, not bent or twisted. Since a skin-on-frame boat without its skin is very flexible, the strongback is still needed even after the frame is completed until the skin is applied, shrunk and sealed or painted. A strongback is not needed for all methods of construction; I do not require one but I do not build skin-on-frame boats.