Keeping clinker dinghies wet

[josephmoore]

Given that clinker planks need to be wet to swell and keep leaks at bay, how do you cope when using a dinghy that spends most of its life ashore on a trolley in the dinghy park? Does it dry out and always be a bit prone to leaking or is it just not a problem?

 

[pmagowan]

For small dinghys it tends to be less of a problem as the movement is related to the size of planking. They also often have flexible sealant on the lap.

 

[chinita]

Mine - early sixties mahogany on oak - is used as the OP describes. Leaks like a sieve, my feet get wet, by the time she has taken up it is time to put her ashore again, have learned to live with it.

 

[Wooden Boat Fittings]

As we know, clinker construction is of overlapping strakes, each fastened to the others at the laps with copper rivets. The strakes have to be joined tightly enough that they resist the ingress of water. The way this happens is that, when afloat, the wood comprising the strakes takes up water and swells against the tension in the rivets, thereby tightening each lap to the point where it becomes essentially watertight. If the hull is allowed to dry out, the wood in the strakes shrinks and the laps open up; and if the vessel is then launched she will attempt to sink. For a dinghy like my 15' Aileen Louisa, and I imagine for Chinita's dinghy too (at least to some extent) the taking-up process can take half a day to be completed to the point where the boat can be used, by when it’s almost time to put her back on her trailer to take her home again....

The ‘correct’ answer to the problem is to leave the boat afloat somewhere all the time, so that she’s always available for use when wanted. I was lucky when I had Aileen Louisa that I was living where my back gate opened on to the water, and I could leave her in her mud berth all the time. That way the hull stayed watertight and she floated on each tide, ready for use. With a boat stored on her trailer, some other way of keeping the hull wet is required. It is not okay to fill the hull with water like a bath because of the risk of damage to the hull -- boats are not designed to keep water in, but out, and the weight of water inside could damage the hull, even to the point of destroying it altogether. But it is okay to put in enough water to cover the garboards and maybe one more strake on each side; and having done that you can then lay towels or pieces of carpet against the inside of the hull from there to above the waterline; leave the bottom edges in the pool of water in the bottom to wick the water up, top up the pool from time to time, and if necessary keep the towels wet with an occasional sprinkle from the hose as well. If you do this for a day or so before launching she should float without much leaking.

Another method I've heard about but not tried is to use garden sprinklers under the hull for some time while it's on the trailer to wetten it from the outside, and I can't see why that wouldn't work either (except perhaps in a yacht club, where it mightn't be so easy to organise).

And a third option is to use a waxy product called Slick Seam, trowelled into the laps between the strakes from the outside. This seals any gaps pretty well, but oozes out under pressure as the wood swells in the water, therefore avoiding damage to the strakes. (But what you should not ever consider doing is using an epoxy filler or even an elastomeric compound to do this, because these products stick to the strakes and you risk permanent damage to the wood as it swells against the filler.)

Mike

 

[Capt Popeye]

Can I ask /suggest that the dinghy be stored upside down and a cover placed over it to keep the direct rays of the sun of the timbers so helping hopefully that the dinghy does not dry out. Oh raise the dinghy on blocks to allow fresh air under it.
Or tar the bottom to just above the waterline

 

[Wooden Boat Fittings]

Eric Hiscock once said that to properly waterproof a dinghy you should fill part of the hull with a puddle of raw linseed oil, moving the hull around bit by bit so the oil penetrated every part of the planking in due course. Once finished, the hull would stay waterproof forever.

Mike

 

[Malabar]

I always understood that salt water in the bilges does little harm; fresh water leads to rot. Worth bearing in mind.

 

[Woodlouse]

Presuming that the boat is not bare timber then it shouldn't dry out too quickly. Keep it in a shady spot and if the boat is reasonably tight then you shouldn't have a problem. With my dinghy it usually takes a day to take up at the start of the season and after that is fine other than the occasional trickle.

 

[josephmoore]

Interesting stuff guys, thanks. It'd be a very occasional use thing as a tender and for some quiet evening sailing on the river so perhaps keeping ashore in the dinghy park wouldn't be the way to go. Just mulling my options for when my rapidly deteriorating inflatable finally gives up the ghost

 

[Wooden Boat Fittings]

Ah. Well, if you don't yet have your clinker dinghy, get a glued ply one when the time comes and you can leave it on its trailer with impunity for as long as you like.

Mike

 

[pmagowan]

You could, of course, completely seal the wood with epoxy. This would only work if you managed to get it completely sealed inside and out otherwise the expansion and contraction of the wood would simply tear it away from the epoxy layer. If you do it properly, with some fibreglass for abrasion resistance then it should be totally waterproof all the time and also much less susceptible to rot.

 

[121]

Dig a pond.

 

[chinita]

You could, of course, completely seal the wood with epoxy.

I think you are in the wrong place. All the Satanist threads are going on in the Lounge.

 

[Even Chance]

Sikaflex on the outside of the laps (BUT it MUST be bare wood before doing this!), just run a wee bead and smear into a fillet with a gloved finger. Two tubes is enough for a 12 foot clinker dinghy. It paints over easily, and the boat will never leak again. Did this to my dinghy years ago, and its still perfect. Its kept on a trailer in a garage, so leaked like a sieve every time it was launched. Not any more!

 

[CalicoJack]

When you recover the dinghy throw 2 or 3 buckets of sea water into it. We then cover it with a white (so that it doesn't get too hot) water proof cover so that the water cannot evaporate easily. Ours is on a trailer and we raise and lower the front of the trailer to get the water in different places, leaving it for a day or so in each position. We have had ours for 20 years and it seems to like this treatment. It still weeps a bit when first put in the sea, but not too much. Some boats let more in than others. I was talking to the owner of a commercial boat which had been built by Lowers of Newhaven, who had brought a boat that had been beach launched at Hastings. He had fitted three new electric bilge pumps, one ran all the time, the second cycled on and off every few minutes and the third was just in case!

 

[Cyberusfaustus]

Dig a pond.

What advice can any of you share who have done this to keep their boats wet? I have a large yard and an considering this. Possible versions include a custom aboveground stock tank and a shallow pond with a liner. Both be of these plans would require a gurney to raise and lower the boat. Last option is a larger one that I can trailer "launch" into... But only big enough to mud berth - not sail. Thoughts? Experience? Suggestions? Warnings?
Thank you.

 

[Capt Popeye]

I visied Chatham Dockyard many times before it was cloaed up , often to view the Small Craft Disposals on view ; do not recall any Ponds for the Timber Craft there , only Ponds for the Masts and Spars ; But the Small Craft were stored in sheds ,with windows blanked out . to keep the Craft cool and Sunlight off them ; Also covered in Tarps to keep them cool ; Rainwater can destroy a Timber Craft , as in Rainwater leaks through decking etc ; So my guess is that Timber Craft should be protected from direct Sunlight and warm /hot storage places , but not necesarily placed in Wet areas or have water inside the Hull ; Cool and protected from Sunlight withoiut Wrm air being allowed to get through the hull

 

[jakeroyd]

Had a clinker built National 12 dinghy (built in the 1950's ?) years ago.
Used to sail her on lake Bala.
We used to arrive on Friday afternoon and slip it in the water off the road trailer.
It would sink in 2 or 3 foot of shoreside water.
Then bail it out in the morning to sail it.

 

[Romeo]

Sail it more often, so it does not dry out completely. At the start of the season, consider sinking it for a couple of days. Don't fill it with water when ashore...... the planking is not designed for that sort of load.

 

[Capt Popeye]

Sail it more often, so it does not dry out completely. At the start of the season, consider sinking it for a couple of days. Don't fill it with water...... the planking is not designed for that sort of load.

Quite so quite so : A boat , especially a Racing Dinghy is quite carefully constructed to sail fast , not act as a Water container; After all Rain Water is surely a Timber boats worst enemy ; Keep rain water off and out of timber boats , always