Thuyền thúng Coracle -- the first sod is turned

Today I marked out the preferred circumference of the Thuyền thúng Coracle: 1.3 metres

< Coracle in situ and in drydock, showing marker width. A virtual coracle.

Why 1.3 metres? That's the width I can comfortably fit on top of a car or drag behind a bicycle on a trailer. It is -- I hope -- big enough to support me, my weight and my fishing gear.

I wonder if it's wide enough...but given my projected use -- inlet fishing, so long as it floats, I reckon I can remain buoyant and seaworthy.

Vietnamese coracles don't have seats, but I was thinking I'd prefer somewhere to put my bum for  a few hours each trip and had planned to simply tie on a milk crate. But when I sampled that option, I found that I'd have little room for my feet between the crate and the sides of the craft. So I tried the simple plastic pedestal. Works fine -- if I want to carry a seat. With this seat in place, in the water the coracle  will be like a floating mushroom.

Seated I got a feeling for the lie of the land/water and recognize that with my limited diameter I'd need to take care how far my lip rose above the water line. This is a factor of how steep the hull and how broad the underbelly.

Once I get my measurements sorted the construction process will begin  at  the very spot photographed.

1. I build up a plug from old bricks and stuff, such as milk crates.
2. I cover this with supermarket plastic bags filled with soil or sand.
3. To sculpt the final shape over this I think my best bet is  to throw down a layer of plaster and cloth.
4. Once smoothed and modelled  I can then begin to use the shape as my (upside down) coracle (male) mould

I'm still exploring my material options -- but a recent suggestion of Cascamite, Extramite, Polymite, Wood Glue looks exciting.

Either that or Acrylic house  paint -- Dulux Weathershield. The draw back with  the acrylic paint is cost (as well as a nagging suspicion that the process won't work).

This product may have changed its name over the years but its still the same powdered urea/formaldehyde resin glue, for cabinet and dinghy building. It is afully gap-filling, water resistant (when tested against DIN Spec. 68602/3 Section B3), mould resistant and non-staining, and is approved by Lloyds Register of shipping (Certificate No. YSC/QA 115) under the Society`s Quality Approval Scheme. 
This adhesive produces a bond stronger than the timber.

Mixing

By Weight
Use 2 parts of Cascamite powder to 1 part of cold water.
By Volume
Use 3.1/2 parts of Cascamite powder to 1 part of cold water.

So given that my building material is Kraft paper the glue may suit. My initial objection to resin coatings was that they were one layer between me  sinking and I wanted to be able to recoat as required, even strip back -- preferably annually. So now I'm thinking that I'll combine what ever depth I can with this glue as a paper-mache mix then use the Acrylic and  paper as an external overlay coating. The solidity of the glue -- no  flex? -- will give me a firm base.

Coracle sailing? Source: The (English)Coracle Society

Production update on the Thuyền thúng Coracle

I have been experimenting with materials and my seemingly rigorous tests have really put the kibosh on a strict papier mache regime. The glues act  to transmit   the moisture and the adhesion collapses. Weighed down on the bottom of a tank, the sunken craft turns to lumpy porridge.

The standard solution of using an outer coating of 2 pack polyurethane is not what I want to do.  But I was researching waterproof coatings for outdoor wood and concrete  and considered 'acrylic elastomeric coatings'  -- which while they will suit the job as an outer coating, may be too heavy for papier mache.( so I am told by the paint company).

But really, my consultant said, a very good acrylic/latex outdoor  paint  will do the  same job at much less cost.In fact boaties here swear by a house paint acrylic -- Dulux Weathershield for their boat exteriors above the waterline.Any below the waterline paint is  usually an expensive enamel . But today the preference has run to using 2 pack polyurethane. rather than enamels.

Another key consideration was that i wanted to recoat the craft maybe annually if necessary and enamel -- and polyurethane especially -- doesn't lend itself to that easily. With acrylic you wash, sand back a bit and paint. All with water clean up too.

So now I'm experimenting with   Weathershield -- all weather -- acrylic house paintto which I've added an acrylic paint condition Floetrol .

The additive gives we a longer dry time and easier, smoother  spread. But the trick I'm exploring is a bit lateral -- I'm using the acrylic paint as an adhesive so that I'm making the model (for now only models) out of Kraft paper and acrylic house paint layer by layer.

Full House/Coracle

I wear disposable gloves and find that I have to dunk the Kraft paper tears in the paint then scrunch them up and wring the paper so that I get a deeper embed of the acrylic. I then apply it by hand to the shape and smooth it down by massaging the layers together.

The acrylic mix however makes the shape very flexible, and I wanted much more stiffness. With a standard papier mache mix I'd get a stuff result.

Is it the paper or the paint? What if I experimented with newsprint? Should I consider adding cotton or linen (or canvas?) ragging?

The blend of paper and acrylic can be torn  along a seam (like cotton can be) if I don't manage a good level of thickness. So  I have to think this is a multi layer project and I may need reinforcement by embedding  other materials beside paper.( eg: bamboo, cotton, linen etc?) So far I haven't worked out how to best mesh the paper layers for greater strength and stiffness.

The general lesson is this: if this works then you could make any structure out of paper and  outdoor  acrylic paint so long as you re-coated at intervals while it was outside. But the internal structure would remain dry. as each layer is protected by its own coating of waterproof paint utilized as a glue.

How strong and waterproof is this paper acrylic mix? I'm still doing tests. But obviously as an option to using standard papier mache glues, it works. Paint technology -- esp house paint technology -- is a big deal esp over the last 10 years and the ability of the paint to adhere to surfaces, even suspect surfaces, is seriously addressed in the lab and in situ.

I laid down maybe ten layers of Kraft paper and now have a convex frisbee  that flexes (more than I wanted). So I'll sand back the top layers and lay down some more paper  to see what impact more coatings have on stiffness.I'll also need to explore other materials in the mix such as canvas, linen ( which I will next)& cotton. (I'm thinking that I'd crisscross strips of these materials to see  if (a) they adhere and (b) they strengthen and (c) give the shape rigidity.

• Thuyền thúng  photo gallery
• Thuyền thúng launching for fishing
• Video: basket boat race

Paper boating: experiments in keeping afloat

I've been a busy beaver walrus making little models of the coracle to be.

Easy done it is too. While I used my proposed plastic sand bags building technique to construct the SS Enamel, the other two in the fleet were simply papier mache construct over kitchen bowls.

With SS Penetrol I also laid down a layer of linen/cotton cloth, but besides that one feature, both it and SS Acrylic are all paper and glue. I experimented with SS Penetrol by  laying down Penetrol strata as I built up the layers to see if I could adhere paper/glue layers on top of Penetrol ones. Penetrol is an oil mix designed to prevent water ingress by soaking into the material and displacing space that  water could occupy.It is used extensively in the marine environment. It is simply rubbed on/rubbed off   a few times.

SS Acrylic uses a very ordinary inside/outside Acrylic  paint with 4 coats on the outside and two coatings on the inside.

SS Enamel is such a mix of experimental techniques that it is hardly a scientific excursion -- so let's treat it as "Control". Enamel paint, main paper layers and bamboo framing.

My hope is that later I  can remove the ships and do an autopsy on their innards to see where and how water, if it did indeed soak in,  entered each hull. My problem is that after several hours there's no soaking and I'll need to add the weight of cargo to the vessels. Stones perhaps.

I also received in yesterday's mail  The Cardboard Boat Book  which is an idiosyncratic  manual on how to.... construct a boat from cardboard.I was interested in a few engineering concepts and the book is a useful reference in that regard.It also relies on masonry coatings and dry wall adhesives  to adhere and protect the build.

The discussion in the book makes me think that the coracle shape suits paper construction as the gravitational forces are spread across the upside down dome. But when I start to add my 100 kgm frame on top of papier mache sitting on water, while  the craft's centre of gravity may shift and move along  the hull,  the concentrated point of my weight at the foot fall will stress the hull at that locus. So while I may be able to fill the coracle with many kilograms of wet sand or soft rocks and sail it easily, a human creature with arms and legs sticking out, moving  about and standing  on its 'deck' is going to be another challenge  all together.

Coracle: A note on glues and paint

I've been researching paint and other top coats in regard to their impermeability.  The problem I find is that 2 pack epoxy  systems and even marine paints carry a hefty price tag.

The other complication is that 2 pack epoxy coatings won't flex and the craft I'm building has to flex. Since I am planning to re-coat the coracle once per year at least , my present grand plan is procedure reliant:

• construct the papier mache hull over a plug/mould. While still on the plug, paint the 'bottom' with undercoat/sealer (which one?) and several coats of Dulux Weathershield Acrylic house paint. Let dry.
• remove the coracle from the plug and turn it over.
• paint the inside of the hull the same way so that there' is an inside outside layer of acrylic paint several coats thick. Then,
• while the paint is  still wet lay down a paper layer over the hull. Let dry. Then,
  
• lay down the support struts made from bamboo. Layer these with paper and cloth and coat the laid rods with Acrylic using it both as a glue and as a coating so that laid on top is paper which uses the paint as an adhesive.
• let dry.
• lay down several new layers of paper over the support struts and hull.Then coat these layers -- in process -- or at the end -- with Floods Penetrol to protect the paper from  water inundation.

 Rationale

Advantage: this is a cheap way to go with easy touch up and re-coating options every now and then. When acrylic dries it becomes impermeable despite the fact that it is water based.

Weathershield is used a lot by  wooden boat owners because it delivers well against the elements and costs much less than marine paint and is easy to use and apply. Since it is an exterior house paint it isn't made as marine  below-the-waterline paint -- but then I'm not going to immerse the coracle in water all the time -- only for a few hours at a stretch..

I also seek to harness the stickiness of the paint as an adhesive for paper layers on top of the paint.

Since I want to use Penetrol 

Penetrol is a versatile blend of natural oils with a penetration power 3 times more than water and a powerful bonding ability. High in solids, non-toxic when dry, colourless and with low odour it is user friendly.

I need to ensure that it isn't blended with acryclic so the separation I propose is one of drying the acrylic first before applying Penetrol.. The justification being that if the acrylic leaks I can depend on the Penetrol to slow the ingress into the paper layers.

Read more:Thuyền thúng Coracle,

Ingredients for a paper canoe

When I get a moment I take notes on how I will build the Thuyền thúng Coracle from paper. While my list keeps changing the main game is to start collecting the stuff I need. In the meantime I  experiment....and takes notes. (none of  which I can share here unless I photograph them).

My short list of ingredients:

• Kraft paper. I've located a cheap supply.
• Sand (for the mould/plug)
• Agricultural water pipe for the rim
  
• Wallpaper paste.
• Bamboo skewers
• Plastic ties and rubber bands
• Deks Olje #1 and #2 sealant and/or acrylic elastomeric coating
• Milk crates x 2
• Old second hand body boards 
• Sandpaper

I had a 'breakthrough" today when I realized I could do a lot with old body boards , cut , 'nailed' and glued together, inside the coracle for buoyancy support, flooring and 'furniture'. "Buoyancy" is in case  the craft  decides to sink.under me as I need to mark the spot where I go down....And these board, every family has them, we have three, left over from when the kids were growing up.I can also purchase second hand ones from Opportunity Shops.

I also ordered The Cardboard Boat Book as a bit of engineering savvy with permeable material technology wouldn't go astray.

One final point in regard to Cardboard  Boating. On his website Dave Friant says this:

How are the boats protected from water damage?

    * The construction process includes covering and sealing all exposed seams of cardboard to completely seal the boat from water entering inside the cardboard layers. Once the seams are fully protected, the boat is coated with a rubberized waterproof coating material. When the sealing and coating is done properly the cardboard is protected from water damage.
    * We have boats that are 23 years old and are still being used!
    * The recommended waterproof coating is an acrylic elastomeric coating used for waterproofing roofs, concrete, and wooden structures. I have had extremely good results with products from Ames Research in Oregon, USA. I have used both their 'Block and Wall' product and their 'Maximum Stretch' product.
    * There are numerous products available on the market. Look for 'acrylic elastomeric coatings' when researching your options.
    * These coatings can be colored with coloring made for acrylic paint. Take your coating to a local paint store and have them color your coating with whatever color you desire.

I will also be creating a Powerpoint and video of the production process so that my quest will go down in digital history. As a side effect, exploring the attributes of paper has encouraged me to get back into sculpture as my tendency to, always in the past , deploy a mixed media approach to my masks and puppets lends itself to paper crafting a lot of different items. I'm thinking  political caricature heads, masks  and figures. The beauty being that when you rely on paper and paste you don't have to keep up a supply of clay which is always a challenge as it doesn't come stocked in supermarket shelves.

Read more on : Thuyền thúng Coracle

Discussion thread on making a paper boat.

I shared a few comments on the Papier Mache  Resource Forum and prompted a thoroughly serious discussion.

ratbagradio

Member

Paper boat, paper canoe, paper coracle...

I see a few threads here dealing with the topic of the paper canoe. There is a resource on the web that deals with making canoes out of paper:
http://kcupery.home.isp-direct.com/index.html
and another (among many) that offers designs for a cardboard boats
http://www.thecardboardboatbook.com/
There's also a major inspirational journey to be read by  N. H. Bishop-- Voyage of the Paper Canoe,  1878
http://www.ibiblio.org/eldritch/nhb/paperc/intro.html
However, it needs to be pointed out that 19th century papers were very different from today's commercial papers and while whole industries existed -- making furniture and  boats from paper, the paper used contained more that just pulp  -- rags were a common ingredient for instance.I've done sculpture and puppetry often with paper clay and I'm now back exploring paper and in many ways I prefer it to clay.

But I'm also back confronting my chronic obsession with the paper canoe. But when  I reconsidered my boating needs I decided  that maybe a canoe is more trouble than it's worth no matter what it is made from, given what I intend to use it for ( around the inlets and coastal wetlands near where I live boating and fishing.) and its length. So I started exploring coracles then found, to my mind, the quintessential paper (sea going)craft project:Thuy� n thúng coracle.

These are traditional woven from bamboo in Vietnam-- they are a floating bamboo mats in a frame -- and represent several types  of small craft that are basket boats 
-- and still built and used in Vietnam, India and Iran. So I'm  building one of these . They are simply woven and painted with resin or pitch to waterproof them. Fisherman paddle them out to sea and ever through the breakers.A  2 metre  diameter Thuy� n thúng  has a maximum weight capacity of 1500 kg, and can carry  up to 5 people!

So, to give it a word: I'm building a very large papier mache bowl in which I  intend to mess about in. My notes, researches, experiments and progress is  being logged here:
http://kickbike.blogspot.com/search/lab … %20Coracle
Since I've had a little bit of background using paper I'm going to rely on irrigation tubing (Agi-pipe)and bamboo skewers to give my coracle structural strength. They are my standbys. I think bamboo skewers, so readily available and so cheap ,  are  a modeler's essential.I've used them like nails, to make arms, and legs for puppets. I've wrapped them in bundles to make rods and drum sticks. So deploying them on a boat for structure comes easily .

Waterproofing?

Interesting enough, traditionally the paper canoe relied on Shellac to waterproof the paper but I also guess that (bees)wax could have been used, as it was in ancient Greece for waterproofing. While I'll never try to rely on Linseed Oil, I'm going to experiment with something similar -- Deks Olje -- which is used on wooden boats today. The problem with relying on a surface cover -- such as with expoxy resin -- is that if that fails you're in trouble straightaway and seasonal touch ups are complicated.

dave riley

dopapier

Re: Paper boat, paper canoe, paper coracle...

Thanks for such a thoughtful contribution.  It is certainly an interesting subject.  I don't know whether you have any experiences of coracles?  They are basically very unstable structures and need real skill to handle them without capsizing.  One of their great benefits is that they can be strapped to the back and carried reasonable distances.  So if you want to look like a tortoise . . . !?
DavidO

---

I'm a PM addict

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CatPerson

Moderator

Re: Paper boat, paper canoe, paper coracle...

I must admit that I have never even seen the word 'coracle' and had to look it up.  They look like a bowl.  If I tried to use one of those, it would need pontoons around it!

This should be extremely interesting.  I hope you let us know how you're getting along with it, with photos.

If you do use shellac, be sure to use the real shellac, not the synthetic kind.  And shellac needs recoating every year or two, as it wears away.

Good luck!

Sue

ratbagradio

Member

Re: Paper boat, paper canoe, paper coracle...

I'm familiar with the British Isles coracle and as you suggest, it's rocky.I wondered about that and it seems that porting it on your shoulders is a determination of size and shape regardless of other coinsideration.

The Vietnamese  Thuyen Thung (pictures below)
http://delicious.com/ratbagradio/coracle?page=3
is more stable and can vary greatly in size. It is also seagoing where the British coracle is now limited to river use. I'm also in Australia by the way -- no coracles here.

These craft sit 'on' the water rather than 'in' it.

One thing nags me however, in regard to papier mache structure. If I construct a round bowl shape and use quality paper as well as criss crossing the layers where are my stress points?

We could imagine that a parallel would be a china bowl which would break if dropped on a concrete surface, but if I am only dealing with stresses from below and  gravity and weight I'm wondering what is the best way to reinforce it.

My problem is that any 'foreign' structure I introduce  up flush against the bowl would only promotes stress points around which the boat could fold and split.So a basket frame structure like the English coracle (made from willow when the hull is canvas) won't do. Better that I use the same material as the bowl to construct struts -- a support frame.

When you consider it, consider the engineering, paper has its own structural rules which I'm sure  should be understood before trying to apply them and as far as I know none of the 19th century paper canoes had internal frames having been shaped over a mould.

dopapier

Moderator

Re: Paper boat, paper canoe, paper coracle...

Hey, this is really interesting.  As Sue (Catperson) says, we will be delighted if you reach a point of being able to share pictures with us all.
Why 'good quality paper'?  It sounds as though you mean expensive stuff.  I find that alternating layers of kraft (brown packaging) and bond (office type) with PVA produces a very strong laminate, at no cost.  Of course it has to be waterproof so in this case you probably won't use SCMC or wallpaper paste at all.   I'm sure you'll try some experiments first.
Stress points?  You mean where it is most likely to collapse?  Well, anywhere really but the weakest area would be around the rim where it would have to be very strong to withstand pressure without collapsing inward.  I would have thought that an internal frame, such as you would use with birchbark etc.  could only be helpful.  The Welsh coracles are a good example, where the outer skin is only strong enough to withstand the water pressure.  The rest is done by the frame.  I haven't looked at the other coracles you mention, but am just about to.   You can make strong frame structures with heavy duty card shaped into squared or triangular tubes but this would be very vulnerable to water ingress.
DavidO

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dopapier

Moderator

Re: Paper boat, paper canoe, paper coracle...

Having looked at your pictures (very nice) I would have thought that the third one makes a good model (the boat, that is).  With the paper laminate you would simply be providing a strong skin.  A problem would be that the internal face must be as waterproof as the outside and the frame would make this difficult.  To overcome this, you could lay aluminium foil a a resist over the frame; laminate over it;  remove the foil (with a big turkey ready for the over?);  pull off the laminate shell and shellac like mad; slip it back on and fix.
What do you think?
DavidO

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ratbagradio

Member

Re: Paper boat, paper canoe, paper coracle...

Well I was going to proceed by creating a mould -- a mound of bagged sand sculptured to shape, covered in cling wrap, and laying the  pasted paper on top of this. The shape would be an upside down bowl, you see -- very straightforward. This was how I've done masks, either with clay, paperclay and other mixes as a mould and if necessary you just pulled the framing material apart to retrieve the shaped item once it dried

With that approach any frame-ing would have to be added later, you see. 

So imagine I then have this very large bowl made out of papier mache. I then upturn it so that the lip faces up, and then begin to lay down "structure" inside the bowl itself, adding several more layers to the rim, and creating a fan effect frame inside the bowl by laying down bamboo skewers, strapped end to end and adhering them to the 'hull' with further layers of paper -- ie just like a paper fan in fact with bamboo ribs. The only alternative I can imagine to this would be to lay down narrow  strips of several layers of paper.

I had this coracle construction process in mind
http://koti.kapsi.fi/hvartial/coracle/coracle.htm
which uses meshed plywood strips for the frame.

I've actually done experiments before with aluminum foil  and found it very resistive to glues but I also don't understand your suggested usage.

On the question of the glues -- I've used PVA and find that since it is plastic it  can often whell up and coagulate between layers whereas cellulose glues are much easier to 'merge' with the paper being, essentially, the same material -- plant pulp. What I mean is that I really lay on a lot of hand pressure when I'm laying down paper layers and treat the form and its paper as clay.

I used to make masks by creating a paperclay slip and cellulose glue mix soaking felt cloth in this then working the felt over a face (mask) mould so that any fold in the felt merged with the material as though it was all pulp. Once I had the profile just so I'd then coat it with a PVA/water mix -- thus plasticating it and laying down a undercoat. I'd then often use boot polishes on the masks or melted crayon wax. You get some exciting effects.

I'm approaching the coracle from the same angle  as I look upon paper or felt as very malleable stuff that can be 'panel beaten' with hands on pressure. Because of its ease of use, I preferred felt for making masks (so long as it hand some natural fibres in it as not all commercial felt has and pure wool felt is far too dear) , especially with the PVA coating and boot polish as they were always lighter and more flexible than papier mache. In fact if you can imagine how wool felt is turned into items-- hats, bags, etc -- you get an idea of the approach. In the same sense of, I guess, using paper pulp in mould and heating it without glues as one guy I know made his masks.

One approach I thought of was in fact to build any frame out of paper pulp rather than strips of paper....as pulp, in my experience (for better or worse nautically) is stiffer and more brittle than layered paper strips. But glued pulp is so fiddly and hard to work with.

As for waterproofing -- as far as I'm concerned -- any saturation is a problem. The paper boat literature errs towards cellulose glues  primarily because there is less chance that the layers will lift from one another and offer channels for water seepage. But no glue is going to replace the protection offered by a good coating and as literature suggests, moisture will eventually find it's way through even an unbroken layer of paint or other surface coating.
http://kcupery.home.isp-direct.com/PBAr … kslaw.html
So that's the key issue -- what you coat with and, I suspect, how often you coat. And most important sand down the hull to baby bottom smoothness.

Since I'm seabound in this I don't want to drown although I'm only planning to muck about in shallow waters -- inlets, tidal marshes, and creeks -- close to shore but maybe within cooee of an occasional bull shark.(And here really big sharks are known to bite surfboards in two!) However, the main thing to note is that these craft sit on the water, not in it so the pressures are spread evenly as a snow shoe distributes the wearer's weight on snow.

dopapier

Moderator

Re: Paper boat, paper canoe, paper coracle...

It all sounds very good sense.  I've used the mound of sand technique for one or two things, though not as big as a coracle.  You have better drying temperatures in Oz than we do in UK. The aluminium foil was only to prevent the laminate sticking to the frame, if you used that method. 
I take your point about PVA.
I reckon the sand method, followed by inserting a frame is really good.  I agree, the pulp would not make a good frame.  Flexible bamboo would be great.
DavidO
(David Osborne, sometimes known as the Ozzard of Wiz)
p.s.  don't make your lifejacket out of pm.  lol

kcupery

Re: Paper boat, paper canoe, paper coracle...

I can not resist offering a few words of advice on paper boats. (http://kcupery.home.isp-direct.com) is my site and I've spent a number of years on paper boat research... but mostly historical. (Paper mache I'm not so good at and confess ignorance of things you folks do).

Anyway, I was recently in a library that has a sample of the paper from the canoe that Nathaniel Bishop used in his  "Voyage of the Paper Canoe", (referenced in the first post). It is clearly as it has been described; a very thick single sheet of linen paper (several mm thick) that has been saturated with a resin of some sort. My guess is shellac, although I was not able to do a chemical test on it (yet).

Secondary literature suggests that the Waters & Sons firm used shellac as part of their "proprietary waterproofing process". They never provided details. I'm guessing it was a mixture of applications of shellac and varnishes or oils (think linseed oil).

Literature also suggests that they used shellac as a glue when making rowing shells out of multiple layers of manila paper.

As for modern canoes of paper, I've seen several that were in sad condition rather quickly. One in particular looked elegant when new, but quickly (one week-end with some rain) became "lumpy". The sad person who had made it used carpenters clue for the paper and a latex paint on the outside. Both are bad news with respect to water.

For amusement some folks build canoes using newspapers and wallpaper paste. They often get a lot of attention, (particularly if you use the local newspaper), but they are indeed temporary boats at best, regardless of how you paint them.

The canoe I built has been surprisingly durable, but I resorted to a marine epoxy resin as a coating inside and out. (I used a Weldwood Plastic Resin to build up paper layers, but that is simply water resistant, not waterproof.) This is sort of cheating I suppose, but I was never really striving for an historical reproduction. More details at: http://kcupery.home.isp-direct.com/PBArtic/TandC.html

Last edited by kcupery (Today 05:48:19)

ratbagradio

Member

Re: Paper boat, paper canoe, paper coracle...

Kenneth Cupery , who should know, captures the quandary  in  a nutshell: layer by layer waterproofing protection versus coating with outer  impermeable shell. I think I'll explore layer by layer in my first model and maybe later, if it is a disaster, try the epoxy approach. While it would be a nice idea to utilize both approaches I doubt that the paper will tolerate the mix.  However (thinks he) if I used a coating like Deks Olje, maybe I can use that as I layer the paper so that I build up layer by layer papier mache *and* waterproofing agent.
http://www.floodaustralia.net/products/deksolje.htm
-- just so long as it doesn't resist the glue which is highly likely. But if the original paper canoe manufacturers  used shellac and linseed oil the option may indeed be viable.

I hope to start my  experiments with Deks Olje next week -- a Xmas distraction.

Ah yes -- my paper of choice was going to be Kraft.

Last edited by ratbagradio (Today 10:50:52)

CatPerson

Moderator

Re: Paper boat, paper canoe, paper coracle...

Keeping in mind that I know nothing about these things... but I would like to toss a few ideas out there...

"It is clearly as it has been described; a very thick single sheet of linen paper (several mm thick) that has been saturated with a resin of some sort. My guess is shellac..."

Perhaps it is my interpretation, but it almost sounds like the linen paper was formed into paper a thick, single sheet expressly for this project.  Could it have been made right from the fibers into a single sheet, rather than laminated or multiple sheets?  It seems that a piece of paper like that would be far stronger, and not subject to the stresses of multiple layers that might have flaws in the lamination that would create weak areas.

Are you dedicated to the idea of a PAPER coracle?  Fabric would be stronger, even laminated fabric.  Imagine a laminate formed from several sheets of (well-laundered) fabric, with shellac used as the adhesive?  And the original, being made from linen fibers, was really closer to being a fabric than a paper.  Our American 'paper' money is really 100% cotton fiber, there is no actual 'paper' (wood fiber) in it.  As with Bishop's paper canoe, I suspect that the term 'paper' had more to do with the process used to make it than the materials used.  For instance, linen and cotton fiber, formed into woven sheets is called 'fabric', but linen and cotton fibers just melded together is called 'paper'.  Linen and cotton fibers are far, far stronger than the poor grade of paper produced today as kraft paper or anything similar.

Wouldn't using a non-waterproof adhesive be begging for problems?  One slight abrasion of the coating, and I would think the moisture would move laterally through the skin.

When boatmakers use fiberglass and resin, they are impregnating the fiber with the resin, not just adding it on the surface.

And I think David is correct in that the rim is your weakest point, as it will tend to flex as the weight (you) in the coracle shifts.  And it would seem that the rim would flex more without a frame than with one.  I cannot visualize anything stronger for the purpose than bamboo that would still blend with your adhesive/coatings. 

I suspect that plastics of any kind would be out of the question, either as adhesives (PVAs) or framing.  The disparity between the materials would probably be too great, esp with the adhesives.  I doubt that you will find a single adhesive that will stick well to paper (or fabric) as well as to plastic.

This is a very interesting project, and a puzzle, too!

Sue

Member

Registered: 2009-12-13

Posts: 6

Re: Paper boat, paper canoe, paper coracle...

I agree with what Sue says  about the attributes of cotton or linen papers -- and a single piece of "paper' too.I had in the past experimented with adding cotton sheets to papier mache projects but it was always disappointing -- esp compared to felting approaches. It was hard to adhere the two materials.  As I said I have used felt before -- for masks-- but a felt that was mainly artificial fibre. It was one sheet sculptured into shape and no paper was involved except in the slip such that I forced the paperclay into the felt as a immersion, embedding the two materials, then sealing it.

The British Isles coracle is made from canvas (and before that, animal skins -- like the Inuit kayak). So technically thats' one sheet of cloth. However, it is still one sheet of cloth that required a protective coating.

Native American paperbark canoes -- such as the Canadian Birch Bark Canoe -- were built using pieces of bark held in place by  cedar sheathing strips and pre-bent ribs, and the sections of bark were chalked together with a gum made of pine and spruce resin mixed with fat .

I have an academic article on how the Vietnamese coracles are made ( sent to me by the Vietnam Wooden Boat Foundation) and aside from the question of waterproof coating they are no more than tightly woven baskets which suggests to me that paper mache criss-cross is not beyond  practicability. The difference being, at least, that bamboo is stronger than paper and the 'layers' are self contained strips.

Obviously a bamboo basket with frame is going to be quite strong but not necessarily more waterproof than other materials with out a protective layer. The tradition of basket boats in Vietnam is rich and various and some very large vessels are made by weaving them.

The largest  of these  measures 12 m in length and can have a load capacity of 4 tons.

I've also played around with the glas sheets used in Fiberglas and they make for a strong , very supportive layer.I've used them to seal outdoor sculptures as an experiment but since I hate using the resin, I used a cement and waterpoofing slip instead. Ten years later, they're still doing fine outside so that material is also a structural option -- assuming it adheres. I even built a small model canoe out of Fiberglas/Cement over a Styrofoam form, but --surprize! -- it was a bit too heavy.

A further complication in my mind is that I've also experimented a little with Adobe -- mud,water, straw and clay -- which also presents a waterproofing challenge. While I'm not intending to build a mud boat, the logic of the process is holistic and it can be a trap to reduce your thinking to one aspect or one material element.With Adobe the very worse thing you can do is lay down a protective coating as the wall or oven, etc has to breath and the materials mix has its own interrelated existence any coating suppresses.

If you think back over the Vietnamese and British Isles coracles I think their hull has to move a bit for the design to work in the marine environment. This makes me wary of pursuing the seeming advantages of a rigid outer coating made from epoxy. It would function I guess something like an egg's shell and once cracked....

So I'm thinking better to get patchy seapage rather a than a Titanic tear -- so long as the leak can be fixed with a splash of something.

So many variables, so much water in the Pacific  Ocean!

dopapier

Moderator

From: UK

Registered: 2004-12-04

Posts: 423

Re: Paper boat, paper canoe, paper coracle...

Well, that's an ambition - to cross the Pacific???
DavidO

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I'm a PM addict

Jackie

Moderator

Re: Paper boat, paper canoe, paper coracle...

This is a very interesting thread. A really ambitious project and one that could throw up all sorts of surpising results. These little boats "coracles" were new to me. Thanks so much for sharing it with us.

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Jackie

don g

Member

Re: Paper boat, paper canoe, paper coracle...

I love my paper mache canoe. while I was building it almost everyone said it wouldn't work. except those who had built boats or knew something about boat building or papermache. I did use the epoxy to waterproof the exterior and interior and it worked well. the sides flex in and out and the epoxy doesn't crack. I was worried about this but I think it has similar qualities as fiberglass and does flex without cracking. I guess it would depend on how much it's flexed. the sides of my canoe can flex in about a 10mm (if picked up wrong) without cracking.

after seeing my canoe a lady told me they had built some paper mache boats on the farm as kids. I think they coated them with some paint or something. they used them for a while and then they started to get waterloged. they leaned them against the back of the barn and the rain had got them soaked through. then the cows eat them.

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CatPerson

Moderator

Re: Paper boat, paper canoe, paper coracle...

Ratbagradio, you say that the Vietnamese coracles are woven, but from what?  Many of the old Native American water carriers were tightly woven baskets from plant materials, so may I assume that those coracles are also woven from grasses or reeds?  I am thinking that after centuries of making them, they probably prefer to weave them out of plant materials that have some natural water resistance.

"I think their hull has to move a bit for the design to work in the marine environment."  Why?  What is your thinking here?  As far as I know, a flexible hull is not the norm, and not required.  The flex is just another stress.  You can float a rock in half an eggshell, but you can't float one as well in half of a soft plastic ball.  Please elaborate, if you don't mind.

You mention felt... wool felt comes from sheep (obviously!), so why not acquire some raw wool and make your own felt?  It would be an interesting experiment to make some felt from clean but unwashed wool (still containing the natural lanolin), and some from washed wool (which would probably accept adhesive and sealant better).

"So I'm thinking better to get patchy seapage rather a than a Titanic tear ..."

With weakened papier mache, is there a difference?  Damp paper is not far from tearing, in my experience.  Modern paper isn't very strong under most circumstances.

I am anxious to see where you go with your ideas!

Sue

ratbagradio

Member

Re: Paper boat, paper canoe, paper coracle...

Eaten by cows? How organic! No I'm not planning to travel very far from shore.

I'd love to see photographs of your canoe, Don.

In Vietnam the basket boats are constructed from various selected species of bamboo. and yes they have been made for  centuries as the coracle is thought to have been a coexisting development from the time of the dugout canoe in Asia, Iran and Great Britain.It is indeed a prehistoric craft.Some researchers suggest that it was used by the Celts to colonize the British Isles.

In Vietnam a coracle usually last about 6 years with everyday use as they are a major fishing and transport craft along the coast and up rivers. They are now also a tourist attraction as any image search will confirm.

Personally, I wouldn't proceed with building a paper canoe as the structural aspects are much more challenging than a 'floating bowl', especially in trying to consolidate the backbone of the thing. The beauty of the round coracle -- even compared to the British oval shape (eg; the Ironbridge Coracle is a classic design)or the pear shape used on one Welsh river -- is that it is structurally balanced and the forces from the water are  more evenly shared. That doesn't impact on where you put your feet or where you sit, but it makes for a simpler challenge in regard to reinforced structure. I'm also intending to add some buoyancy apparatus as all coracles will sink if they take in water.

While  I'm not going to paddle very far at all,merely a few metres from the shoreline  handline  fishing (as I say, around inlets and shallow marshes) it's still worthwhile getting inspired and I recommend reading N. H. Bishop-- Voyage of the Paper Canoe,  1878 online at:
http://www.ibiblio.org/eldritch/nhb/paperc/intro.html
He paddled it down the east coat of the United States.

Some folk have  journeyed the length of many of British Isles rivers  (eg: 8o kilometres was one journey) in their coracles, and one Welshman paddled across the English Channel in his.

In another example , two Welshman intend to paddle across  the English Channel in their canoe made from  boutique waterproof paper they make from sheep manure. Their first attempt was abandoned after their hull took in water.

"We thought if we can make a pooh canoe and paddle it across the channel for charity ," one of them told the media, so they could do right by Welsh Air Ambulance.

In further example, Dave Friant, a civil engineer,  makes canoes from cardboard
http://www.thecardboardboatbook.com/
and sells the DIY book.He reckons he has solved the waterproofing issue  by relying on coatings that are "environmentally friendly".

As part of my continuing research I'll be getting myself a copy. He also offers links to a range of other paper boating resources such as the Cardboard Boat Museum and the Rockport Paper House
http://www.thecardboardboatbook.com/$_alternate1.htm

ratbagradio

Re: Paper boat, paper canoe, paper coracle...

Cat's suggestion of cloth got me thinking --so I purchased a cotton/linen blend today  and have laid some down on my experimental model boat. I boiled the cloth for 15 minutes first. To my surprise it adhered easily to the underlying paper layers.

I will experiment with cloth  on cloth and note the cloth mache threads here in this forum.

I'm really working the paper and the cloth into the form as I'm a once upon a time sports masseur and I got into sculpting because I trusted my hands' creativity. So I like to really put a lot of pressure on the material with my thumbs.

This is my first model and once I've coated it with  chosen coatings I'll be leaving it to float -- loaded with stuff -- in a water trough long term to see how it performs as to strength, buoyancy, and permeability. I even hope to weigh down the model so it spends some time on the bottom. After salvage I'll check the design's  weak points.

With the cloth my challenge is to work out how best to lay it down.  In way of technique  there are a few options.

1) Treat it like paper and layer it strip by strip, one on top of the other.
2) Cover a large surface by cutting slits in the cloth and  mitre-ing the folds then firming  the folds down, maybe even removing overlays.
3) Layer the cloth side by side in strips or patches. so that there is no bumpy overlay.

Technically as Cat suggested I could almost use one sheet of cloth and simply cover the hull with that by slitting and trimming where necessary. However I still need the paper to create the shape and deepen the thickness of the hull.

But it seems to me if the cloth really adheres without any hesitancy I can mix and match paper and cloth layers while noting that the cloth is going to shrink as it dries maybe more than the paper will.

I am then forced to wonder:What happens to paper or cloth if they are forced to cohabit with one another for years? What leaches? Is there a significant acidation? Does shrinkage stabilize? Will both media flex or bend  or dent in unison with one another, or will they pull at each other's adhesion?

Thuyền thúng Coracle: solid bits and waterproofing

I've been experimenting with my scale model and trying to work out structural aspects I need to engineer for my paper coracle.

There are four challenges:

1. The Rim: The best way to make the coracle is to first lay down onto a flat surface  a circular frame. This will become the circumference of the craft.  My problem is deciding what to construct the frame from. Due to my previous experience making puppets and masks, including some quite large puppets, I know that bamboo skewers lashed together make a very strong rod. So my plan is to (i)soak skewers (the cheapest and most accessible form of bamboo as they can be purchased from any supermarket) in water so that they flex (ii)then insert the rod into agi-pipe tubing.(Agi pipe, irrigation tubing, is available from any hardware store).(iii) before bending the piping with the skewers inside into a circular shape at a preferred diameter.
2. The Depth of the Rim: While one agi pipe frame should hold the bowl in place and shape I want a  very strong rim that will withstand a lot of battering -- such as from the working of a paddle. So I'm thinking I will need  4 such tubes lashed together and shaped into a circle or one pipe wrapped around four lashed skewer rods. I'm thinking that zip  plastic ties are the preferred binding both for the bamboo as well as for the tubes.
3. Protection and Waterproofing: The original  Thuyền thúng  is simply a bamboo basket coated with resins or pitch. The British Isles coracle is canvas stretched over a frame and coated with tar. I have to be cognizant of paper's attributes and the fact that the 'walls' are built up layer by layer.So I can use choose to use marine paint or 2 pack epoxy. However, while the epoxy will strengthen and protect the 'hull' it doesn't so easily lend itself to touch ups, and re-coatings each year of use. So I am going to explore Deks Olje  which is a Saturating Wood Protector. You can also apply a gloss finish. However, I don't want the 'protector' reacting with my glue and causing either the layers to peel or the stiffness and structure to collapse.(I intend to experiment).
   

4.The need for a supplementary frame? Technically when working with paper-mache the paper has its own form and strength. Any skilled paper worker knows that  stronger  paper  gives solid results. So I'll be using Kraft paper which is paper produced  from wood pulp.  This is also why I use cellulose based wallpaper  pastes. But as any paper artisan also knows, when you layer the paper with structure in mind -- by criss-crossing the strips or layering them half and half over each strip -- you build in structure. I also always massage the paper layers with my hands pushing and tugging the wet  paper into place and merging the layers by applying pressure. If I was to then introduce a frame  structure as well by adding ribs to the coracle -- made from? -- I'd be running at cross purposes to the papier mache's internal logic and maybe introduce tear points. So I'm thinking that if I laid down bamboo skewers  running from the internal centre of the  bowl/hull I could then coat this net structure with further paper layers. I've done this before. This would make the floor of the coracle slightly corrugated. If I were to make up standalone structural ribs like the rim, they would not be easily integrated into the craft's internal structure and may tend to lift as they have to be added after the shape was made and the mould separated.

So --  it's back to the drawing board and the glue pot I go.

• Read more on this topic:Thuyền thúng Coracle

Constructing a workingThuyền thúng Coracle out of paper

After meditating on a project like this for years I am now  confident I can construct a serviceable craft I can paddle around in -- out of paper.

The main  resources I'm relying on are these:

• My references on delicious
• Resources on paper boat construction
• The inspiring journey: Voyage of the Paper Canoe, N. H. Bishop, 1878 

I've also been greatly assisted by the people from the Vietnam Wooden Boat Foundation -- Ken Preston and Eric Wickberg-- who have generously  shared their knowledge and first hand experience of Vietnamese basket boats.

My project aim is to build a Thuyền thúng (round basket boat)-- which is usually made from bamboo -- out of paper. I'm not talking about a model boats but one you can sit in and paddle.

Before I address detailed aspects, I thought I'd explore the materials I intendeds to use, so I quickly built a process model -- 30 cm wide -- of the boat using the techniques I was hoping to deploy.[See above image. Click on image to enlarge view.].

In temperament and habit I'm a sculptor -- not a carpenter, boat builder, or any sort of a skilled handyman. The DIY of working with paper --paper-mache in fact -- is straightforward and I'm experienced with working with paper, and paper mixed with clay. But when designing and building something that has to float, hold together by relying on its own internal structure and remain waterproof, there are a few challenges that need to be planned for and not left to chance.

However, what currently concerns me is size. While size is not necessarily limited by material, I wanted  to build a  Thuyền thúng  that was:

• designed for single person operation
• deep enough to  keep out and ride with small waves or choppy seas but not so deep as it became unmanageable.
•  narrow enough so that I could put it on the roof of a car or even in the boot. The complication is that that would require a  Thuyền thúng  no more  1.3 metres in diameter when the average size is 1.5 to 2.0 metres.
  
  
  
  But according to Dr. BUI Thi Mai  and Michel GIRARD ,  2 metre  Thuyền thúng  has a maximum weight capacity of 1500 kg, and can carry a up to 5 people. These figures a way above my  performance requirements - SEE: Thuyen Thung, braided bamboo baskets-boats  Of Central Vietnam   “The manufacture of the Thuyen Thung boats of Da Nang (Viêt nam)”  2nd   Congress of the Asia Network/2nd Congress of Réseau Asia-Asia Network  Sept. 28-29-30, 2005, Paris, France 
  

While the coracle of the British Isles is overwhelmingly engineered as a boat to be portaged on the owner's back -- like a turtle's shell (see image left) the Vietnamese version is, I'm told, often rolled to the shoreline or as photographs indicate, can be carried there on a  wheeled device..I guess they may be too light and bowl shaped to be walked on one's back as the scoop would be  an excuse for air lift. although I've seen images of one being carried by resting it on the owner's h shoulder

But it seems to me that while the British and Irish coracles often are oval in shape, seagoing  Thuyền thúng need to be round as I suspect that's a engineering feature that enables the craft to roll over the waves.

The other aspect of shape --and I used to paddle surf skis  though chop and surf --  is that the round shape probably 'gives' in the same way that a spinning top does when it hits a wall.The rotation is also a form of motion as though there's a suggestion that any spin rolls the craft up the obstruction -- such as a wave. I'm not suggesting that the thing is a whirly gig just that the shape allows the craft to merge with the rise in water and give itself up to surface rise rather than try to stand solid , as a hulled boat may do, against it, trying to split the surface.

But I won't know these things until I'm paddling -- and drowning.

Hypothetically, a   Thuyền thúng Coracle made out of paper could be built in a weekend --depending on drying times.-- for less than $AUD50.

So let's see...