wooden boats again

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Novachris

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I am still on the hunt for a wooden boat,even after having my fingers singed on an old lifeboat which turned out to be a potential money pit....however I have found a nice dd teak boat with a recent survey which looks good and all the issue were addressed...but...on a visit at the weekend to look her over he bilges were full of water,'all wooden boats leak' said her owner,but I was drawn back to the survey which indicated a small leak from the garboard strake area.
Should I be worried?
 
So much depends upon the design of the vessel. The chances are that she has a keel stepped mast and, if that is the case, then the potential problems can be quite serious as, it is not just a question of sealing the garboard plank up and in many cases, the problem derives from faulty or failing floors & or fastenings.
You need to be absolutely confident that the survey you are using has been undertaken by someone who really knows what they're talking about.
Sometimes the implications can be tremendously expensive. If it is not a keel stepped mast then the structural issues are somewhat diminished but still should not be underestimated. Unfortunately, it is often the case that if the garboard seams are strained on a keel stepped mast, the situation becomes far worse when the vessel is sailed hard, particularly to windward.

You need to check the survey to see if any garboard (& hood end) fastenings were removed for checking. At very minimum, the surveyor who carried out a survey should have noted that, if none were removed, some do require checking if there is no obvious evidence of these having been replaced or recently checked.
Hope that helps a bit. Perhaps if you indicate the type of boat that might help a bit as some designs do have the propensity for this problem.

You might find some useful information on timber construction & problems on my own website (articles)

Regards


John Lilley

Just noticed the d/d letters ! All change. Must get glasses or bigger screen!
 
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Any wooden boat can in theory be completely rebuilt, but d/diag was never really intended in that way. Look up 'idiosyncratic' in a dictionary ( without wishing 2b patronising)

WoodenShips ( brokers) usually has some really nice wooden boats well built and well maintained on their books, I think you should start 'at the top' rather than with a 'bag of nails' job.
 
Novachris said:
I am still on the hunt for a wooden boat,even after having my fingers singed on an old lifeboat which turned out to be a potential money pit....however I have found a nice dd teak boat with a recent survey which looks good and all the issue were addressed...but...on a visit at the weekend to look her over he bilges were full of water,'all wooden boats leak' said her owner,but I was drawn back to the survey which indicated a small leak from the garboard strake area.
Should I be worried?
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DD was never intended to be a durable method of construction. Its main advantage was that it uses short straight lengths of timber, needs minimal framing and can be built with relatively unskilled labour. Hence its popularity in wartime built naval vessels where speed of construction was important and expected lifetimes short. Obviously teak is a more durable material than others so boats using that timber last longer, but still little you can do about the inevitable leaks and the difficulty of repairs.

Yes you can do good things with modern materials, but repairs are still labour intensive and you need to keep on top of them (34 years of owning a wooden boat type observation).
 
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I think we need to know a little bit about the provenance of this particular yacht.

You say it is teak. Are you sure? I can't recall seeing a double diagonal leisure yacht built in teak.
 
pvb said:
I bet most of the guys who had double diagonal problems tore their hair out and committed suicide long ago! :)

It's a recipe for disaster, just like most old wooden boats.
.
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On the first point you are probably right, on the second you are talking ball cocks. Yes there are plenty of neglected old wooden boats, but there are also lots of beautifully cared for and maintained old wooden boats. Old+wood does not = disaster.
 
Tranona said:
DD was never intended to be a durable method of construction.
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The later wooden lifeboats were built with double diagonal mahogany planking and gave many years of service. For example, the Oakley-class boat, J.G.Graves of Sheffield, was in service for 35 years (according to Wikepedia).

I was always under the impression that the RNLI and its predecessors chose the double-diagonal system because it offered:

- strength

- watertight integrity

- lightness

- durability.

I once knew a man who had served his time at a boatyard that built wooden boats for the RNLI and I remember him saying that the workmanship had to be faultless. If the RNLI inspector found any work that wasn't up to RNLI standards it had to be done again.
 
chinita said:
What is this - twenty feckin questions?

If you want the answer from people who know more that you then don't play games.
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+1

Mate took on a barn find of an ex RN small planing tender. Double diagonal mahogany. Since it had been out of the water for many years and had damage + dried out and open seams, I suggested sheathing it in epoxy/glass, which we did. It will be trailered and stored ashore. The alternative was a complete rebuild of the bottom, beyond the owners skills.

So, what have you got?
 
parsifal said:
The later wooden lifeboats were built with double diagonal mahogany planking and gave many years of service. For example, the Oakley-class boat, J.G.Graves of Sheffield, was in service for 35 years (according to Wikepedia).

I was always under the impression that the RNLI and its predecessors chose the double-diagonal system because it offered:

- strength

- watertight integrity

- lightness

- durability.

I once knew a man who had served his time at a boatyard that built wooden boats for the RNLI and I remember him saying that the workmanship had to be faultless. If the RNLI inspector found any work that wasn't up to RNLI standards it had to be done again.
Click to expand...

Absolutely correct on all counts. Its just that when things get neglected or go wrong with DD is tricky, albeit perfectly possible to repair.
 
We used to have a converted lifeboat which had "double vertical teak planking" which unlike "double diagonal" had each plank overlap by one half plank width and this boat did have a leak at the equivalent of the garboard area.

You asked if a leak at the garboard was something to be worried about. In a conventional carvel planked hull, then it is a simple matter to caulk the seam between the garboard and the first plank. In double diagonal or double vertical boat construction, the join between the diagonal planks and the keel is a bit more complicated in that a number of diagonal planks may be giving rise to the leak and the equivalent of the garboard is behind the planking. (well it was in ours)

In our case the gap between the ends of the planks and the keel was non existent and being double vertical, there was no garboard plank to caulk. We had narrowed down the leaking area by running the boat up on the beach and dried the bilges out and waited for the tide to come in. We came to the conclusion that the was over a length of about two feet.

The boat was hauled out for the winter a couple of weeks later and we inspected the suspect area but there was nothing very conclusive and as said earlier, there was no really gap so we very carefully eased out a narrow groove and let it dry for the winter. The following Spring we troweled in some form of non setting gunk my Father had come across, launched the boat a couple of weeks later and never had any problems over the next 10 years.

As to the reparability of double diagonal, it is not for the faint hearted as replacing one single internal plank could mean removing a number of planks on either side. This was bad enough in early construction when there was a layer of calico between the planks but if it is of a newer type of DD construction were the planks were more like veneers and clued together that is a more difficult repair and may end up being a bodge with polyester resin and mat.

I have to say it would be helpful if you could advise more on the boat, its builders and the type of DD used in its construction as my description above may not be relevant.
 
parsifal said:
The later wooden lifeboats were built with double diagonal mahogany planking and gave many years of service. For example, the Oakley-class boat, J.G.Graves of Sheffield, was in service for 35 years (according to Wikepedia).

I was always under the impression that the RNLI and its predecessors chose the double-diagonal system because it offered:

- strength

- watertight integrity

- lightness

- durability.

I once knew a man who had served his time at a boatyard that built wooden boats for the RNLI and I remember him saying that the workmanship had to be faultless. If the RNLI inspector found any work that wasn't up to RNLI standards it had to be done again.
Click to expand...

Agreed. But there is a world of difference between a no expense spared RNLI build that is subject to constant maintenance compared with a typical DD MOBO that was put together to a price and has suffered decades of ever changing owners who move it on when the jobs get too big.
 
''Thanks for the feedback guys, I think these old boats can be given a new lease of life with the range of glues and epoxies available these days.''

Sorry, OP, but that is EXACTLY the wrong thinking..Too many eedjits slap a bit of epoxy and filler between the double diagonal layers in an otherwise flexible boat that has calico or silk between the planking layers... Result? You've created a hard spot in a pliable structure

(But, wtf do I know or can I suggest eh?) I think you can discern where I am trying to lead you on this one..

Best of luck, use a surveyor at least, and enjoy all aspects of the ownership process..
 
parsifal said:
The later wooden lifeboats were built with double diagonal mahogany planking and gave many years of service. For example, the Oakley-class boat, J.G.Graves of Sheffield, was in service for 35 years (according to Wikepedia).

I was always under the impression that the RNLI and its predecessors chose the double-diagonal system because it offered:

- strength

- watertight integrity

- lightness

- durability.

I once knew a man who had served his time at a boatyard that built wooden boats for the RNLI and I remember him saying that the workmanship had to be faultless. If the RNLI inspector found any work that wasn't up to RNLI standards it had to be done again.
Click to expand...

Quite a lot of RNLI boats were in fact triple diagonal such as the Barnet Class.
 
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