Green or seasoned oak for shipbuilding?

[profchris]

A recent conversation with my wife moved from the new book by Julian Barnes, through John Evelyn's lament about the destruction of woods, to oak framed building construction and thence to ship building. Don't ask, it's all rock and roll stuff like this in my house

But we then wanted to know whether oak-built ships used green oak (easier to work, and should stay fully humidified so won't distort like timber buildings) or seasoned oak (which would surely move as it absorbed water). I said at least one of you lot would certainly know the answer - posting in hope that I'm right!

 

[Jameshow]

I think they would use dried timber for the frame and green oak (or larch) for the planking.

The dried oak gives stability whilst the green oak bends much more easily, even more so if dumped in the river for a few day or in a steamer for a few hours...

 

[heimlaga]

It all depended on the quality specified for the ship and the longevity desired.

The best and most long lasting ships were built using timber that was at least somewhat seasoned. Cheap mass produced iron fastened merchantmen as well as warships built in a hurry to fill gaps in wartime were often built from green timber.

Green timber tended to dry out somewhat and it was softer. This means that joints became sloppier so the hull worked more in a seaway and was moreprone to hogging. The caulking didn't sit as firmly as green timber was softer and didn't swell after launching. The tar used as rot preservative did not penetrate into the timber but formed a skin on the surface instead.

Planks to be bent were in good quality work first air dried then softened in a steam box which doesn't make the timber swell quite to it's green dimensions. As the hull took up after launching all joints became tight and the hull became more monolithic.

 

[RobinBHM]

A recent conversation with my wife moved from the new book by Julian Barnes, through John Evelyn's lament about the destruction of woods, to oak framed building construction and thence to ship building. Don't ask, it's all rock and roll stuff like this in my house

But we then wanted to know whether oak-built ships used green oak (easier to work, and should stay fully humidified so won't distort like timber buildings) or seasoned oak (which would surely move as it absorbed water). I said at least one of you lot would certainly know the answer - posting in hope that I'm right!

curved components were cut and shaped green

I cut up some green oak once for a boat builder -I couldnt believe how floppy and bendy it was

 

[mikej460]

A few years ago I read Pepys Diaries and recall his time in several admin roles in the Royal Naval where the described the procurement and use of oak for shipbuilding. That thought led me to this Shipbuilding Part I Bronze Age to 1700 | The Dover Historian if you scroll right down or do a 'Find on page' to the section called Shipbuilding and associated trades it describes exactly how the oak was processed and how hemp and pine tar was used as caulking. I guess the air dried oak swelled in the water compressing the caulking to form a seal. Interesting stuff, especially reading that it took 40 acres of oak to make one galleon!

 

[stuckinthemud]

Wooden boats need to be kept well ventilated or the wood will sweat and rot in very short order. One issue specific to oak vessels is the metal used as fastenings, iron was often used but would corrode quite quickly in the acidic timber, especially in the salt water and even more if the wood was salted to prevent rot. Cheaply built ships from green oak with iron fastenings tended not to last long and would get “ iron sick” quite quickly

 

[profchris]

Thanks all! Lots of interesting and informative info here.

 

[Jameshow]

Also modern wooden ship building was done for 100s of years, and what was standard Greenwich might not be in Gweek, or Oban....

 

[Adam W.]

"We need a new man o' war to fight the Spanish."

"Sure, I'll cut the oak, but you'll have to wait at least 10 years for it to dry before you can use it."

That doesn't sound like a good plan and I reckon it was used as soon as it was felled and arrived at the docks.

They were big ships and just imagine the storage required for that much wood, especially if you wanted four of the things.

Turner would have made sure to get the scale right when he painted them.

 

[Adam W.]

Just for fun..

 

[baldkev]

On the sampson boat co "tally ho" project, leo used green oak, cut for him, to make the frames ( ribs )

 

[Keith 66]

Ships would often be assembled from partly seasoned timber & the frame left to season or "set" as it stood, this allowed less chance of the timber warping when they hung the planks & finished the job. A lot would depend on the builder & how rich the customer was. It was common for some yankee ships to be built very quickly often from less durable timbers, profit being put before longevity. Some were regarded as worn out at 20 years old.
Smaller working boats will mostly have been built from oak & timber as well seasoned as could be afforded!
Problem with oak framed iron fastened boats is they have a finite working lifespan of approx 50 years, the tannic acid attacks the iron & they start to deteriorate, Once the frames go its rebuild time.
If you look at Thames barges there are many that were around in the 70's & 80's that are now derelict & way beyond economical repair, Ten years of neglect will render any such wooden ship a wreck with no maintenance.
When steaming timbers in small boats green timber is always preferable & the small sections dry out fast after steaming.
Re Tally ho, Leo used Live oak, this is an interesting timber & an evergreen, it is not closely related to what we would use in the uk. Live oak was renowned for its durability & strength & was specified for the frames & hull of the USS Constitution.

 

[heimlaga]

It was rekoned in Finland in the late 19th century that the volume of timber needed to build a wooden merchant ship including masts and spars for the rig and stocks and sleds for launching though not including workplace props and scaffoldings equalled the volume of a box with the lenght and width and height equalling the extreme dimensions of the hull.
Imagine then the amount of timber needed to build a ship of the line which had to be a lot more solid to carry the weight of the guns and to survive being shot at.

 

[whereistheceilidh]

You could try a book source like 'Ships of British Oak' by A J Holland. Focuses mainly on shipbuilding in Hampshire but the principles & practices are similar across many parts of the UK tho the timber species varied.
Many ships were fastened using wooden pegs...trenails (treenails)...so avoiding rust in iron fastenings. When they were used, iron fastenings were tarred or later hot dipped galvanised as was the case with wooden Thames barges.
I have had the pleasure of going out in the New Forest to select large curved timbers for careful cutting by the old sawyer & his son for seaoning as stock for the repair in a number of years of wooden boat frames. There are a number of problems using fresh timber for boats/ships as others have mentioned.