Clinker Boats

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I have recently acquired a clinker built Kestrel 22 which I propose to renovate. General wood and metal work I can confidently carry out. However, the 'clinker built' bit worries me. How do you make sure that when put thge boat into the water the boat is not going to just sink? I have heard tell of letting the boat take water up to expand the planking. It begs the question - if the boat is properly paited how is this going to take place? Is there a good book that covers the subject fully in a pragmatic fashion? Most books I haved read so far give the impression that the writer has only read someone else's book on the subject and not actually done the work themselves.

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tillergirl

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I owned a 25ft clinker centreboarder some ten years ago when she was a good 20 years old and she is still going strong today. Each spring, I painted her and the yard craned her in. Always she leaked. Once or twice she leaked to such an extent it was a close run thing whether she could be rowed to the pontoon to get an additional pump in before she sank. But that was only when I was late putting her in after (in both cases) a very dry spring. What seemed to exacerbate the problem was a lot of wind on dry days in the spring. The application of the best paint job in the world will not stop the planks taking up. I say this on the assumption that you cannot see daylight under the lands now. The last thing you want is paint or caulking or anything else in that joint. The joint is a wood to wood joint with no paint/glue etc and it is the swelling of the wood that makes her watertight. Always after four tides (two days) she took up and sometimes quicker.

If you can see daylight between the lands, you might have a section that needs refastening - ie remove the copper roves, get the section to overlap kindly and tightly and refasten. I never had to do anything so extreme but there was a guy in the same yard with a clinker Stella (25ft) who embarked upon a complete refastening. It took some time but was successful. I'd be surprised if that was necessary. It will be disconcerting to see water gathering in the bottom but more times than not it takes up. If you think she is going to leak a lot, you will need to think about some electric help for the pumping unless you'll going to stay up all night! Just to reassure you when everything is looking bad, when I was a kid, living in Nottingham, I used to hang around the boatyard where my father keep his boat. One summer, the yard launched a river launch (the type with the open front and a large glassed saloon at the back) and myself and another lad bailed it furiously with two buckets for about an hour to keep it afloat and the water level below the electrics on the engine. Suddenly like someone had shut the door, it stopped leaking and never leaked again that season.



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DanTribe

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I used to own a clinker built Stella. every season when first launched I would sleep aboard for the first couple of nights to pump.You soon learn the technique of sleeping with one arm out of bed to get an early warning of rising water.Years ago the process of "taking up" was called "plimbing" but I haven't heard that expression for a while.It's almost impossible to achieve completely a waterproof paint system without using an epoxy saturating technique, which is a subject in it's own right.Clinker boats, in my opinion should not be allowed to dry out too thoroughly, as the planks are liable to split. You will no doubt soon acquire the ancient skill of copper rivetting, it's amazing how many nails there are in even a small boat.
Good luck with your project.
Dan

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Peterduck

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Before you put the boat into the water, run a hose inside it and try to fill the boat with water as high as you dare. This will usually be to the bottom of the engine. If there are any leaks, they will show themselves quite clearly, allowing you to inspect theplanking at that point for any damage. If no damage is found, assume that it is normal shrinkage, and allow it time to take up. Keep the water level inside up to your pre-determined point. When it stops leaking, pump it dry and then put the boat into the water. The area of planking which was above the internal water level and is now below the external water level will now start to leak, but it will be much smaller than if the whole of the boat's bottom were to be leaking. Just keep pumping it out until it stops coming in, which may be anything from an houir to a day, depending on the boat. If you can secure the assistance of a mains-powered submersible pump before you launch, do it, and place it in the lowest place inside that you can. Set up a power cable to the spot where the boat is going to stay sdo that it is ready to go immediately. Dont wait until the boat is in the water before you try to find a pump. Alternatively, if the boat is to be launched in a cradle, leave it in the cradle while it takes up, so that it can't sink.
Peter.

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spark

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Before you paint, scrape off anything that's mobile paying particular attention to the lands (the joint between two planks). When the lands are clean and dry run a bead of oil-based mastic (NOT silicon, polyurethane, or anything that cures) along the lands, following up with a moist finger to squeeze it in. Ideally leave the mastic for a couple of days to skin off but if you don't have time take care when you are painting not to brush the mastic out of the lands. When the boat goes in the water the pressure forces the soft mastic into any cracks and stops (or, at worst, slows down) any leaks. As the wood expands the soft mastic is forced back out again, doing no damage to the integrity of the lands.

The foregoing assumes that any gaps are simply the result of drying out. If you have any cracked planks they must be repaired. If you have a severely dried out hull with flakes of old paint/sand/dirt trapped between the planks then you must remove the fastenings to relieve the planks and clean out the gap with a hacksaw blade.

I would advise against filling the boat with a hose. Even a bilge full of water puts horrible stresses on a clinker hull: exactly opposite to what the hull is designed to take.

I would also recommend keeping the boat in the water 12 months of the year, only coming out for a week or so in the spring (before the weather gets too hot) for painting, etc. This is how clinker fishing boats work and they never leak from drying out (only from use and abuse).



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mickshep

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Instead of filling the boat and risking straining everything, we used to lay sacking in the bottom boards then damp them down, leaving them in situ for a few days and keeping them wet helped the hull take up before the launch and was very effective. Mike

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Thank you for vyour comments. I will try the technique when ready to launch.

Mike

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Casey

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To keep my Oakleaf clinker built boat wet before launching last year I used a garden spray filled with sea water. I found that if I did it regularly enough then little water came through the lands but if left more than a few days then I had seepage.

This was also the year when I had all paint below the water line removed by sand blasting. The paint in the lands was removed by hand. I then built up the underwater paint using the Blakes system. I found that she took up within a couple of hours of launching and took no more water aboard provided she was kept upright. When sailing heeled over was a different matter! Stripping the paint of the hull this year may have improved matters.



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canalman

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My Boat is on a canal, i am concerned that if it is left in all winter it may have problems with ice, the canal freezes at least twice a year, usualy only by an inch or so, but could this be a problem?

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canalman

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If the timber is wet, can you paint the buildge? i would lke to do somthing to clean up the inside of the hull, but if the idea is to keep it "wet" what could you do, preferably whilst still afloat.

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canalman

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On a similar subject, ifthe buildge is always "wet" can you paint it? is so what with?
I would like to clean up the inside of the hull which has had no atenshion for many years.

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ghilliedhu

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I have a small 26ft climker double ended sloop which is hauled out in Oct and put back in the water in May.
Keep her as well cvered as poss but with plenty of ventilation. It seems that the wind has more of a drying effect than the sun.
I put a few bucket fulls of sea water in the bilge if I think that she is starting to dry out and rather than hessian sacks I use the capillory matting laid from the bilges up the planking. The capillory matting is used to help watering in green houses and easily avaiable.
On going back in the water she usually takes in a gallon or so per hour for the first few hours and has completely plimmed up by the following day.
It is amazing how strong and watertight a bunch of planks and nails can be!
David

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