Did 18th and 19th century ships have flat weatherdecks?

[Rushdie]

I'm building Lady Nelson and have reached the planking of the weatherdeck.  I was wondering, were decks in those times "flat", or is the centerline "higher" than the deck level at the whales, enabling any water to be evacuated naturally through the scuppers?  

 

I've boarded many contemporary ships in my life, and only once have I seen a vessel (Norwegian, built around 1949) where absolutely every "horizontal" surface was curved slightly downwards towards both boards.

[GrandpaPhil]

Weather decks would have been curved for ships of the 18th and 19th centuries to improve drainage.  The water would have gone overboard with holes through bulwarks at the deckline called scuppers.

 

There is an excellent diagram of standard deck curvature in zu Mondfelds Historic Ship Models.

Edited March 2 by GrandpaPhil

[popeye2sea]

Flat decks would be a problem for wooden ships.  Flat decks leads to standing water.  Standing water leads to water infiltration.  Water will always find a way in. Fresh water infiltration leads to death for wood ships.

It doesn't take much camber for a deck to be effective at shedding water.  You may not even notice it.

Regards,

Henry

[wefalck]

I gather the answer is, as often, yes and no ... camber seems to have been also subject to fashion. It seems to have become gradually flatter over the years, but was always there in wooden ships. For iron- and steel-ships the situation is a bit different and also a question, whether they had wooden decking or metal decking. Wooden decks always had a camber and usually metal gutters or water-ways to take water away from the edges of the wood. Metal decks can be essentially flat.

 

From a constructive point of view, the camber not only serves to shed water (which, btw is only really relevant, when the ship sit upright in the water and doesn't move much), but also to predetermine in which way the beams will deform when under stress. A curved deck-beam will always bulge up, when under compression in the sea, while a straight beam could do it either way and in different ways from bow to stern. Such movement could lead to a leaking deck, as the planking would be stressed much more.

 

[Rushdie]

That sounds very logical and reasonable, thank you! The Lady Nelson kit I have doesn't provide for camber, and I'll have to consider whether I'll take the risk of complicating this, which is my first, build.

[wefalck]

I don't know the kit, but perhaps one can sand a slight camber into the deck-planking? You would have to check, how this works out with the water-ways etc.

[Jaager]

I did not see a log with the deck being laid in process.  It looks like there is a one piece sub deck on top of the molds and individual planks are laid on top.

A deck curve should be easy to add.  Use actual deck beams.  Now the thickness would be much less than an actual deck beam.  The middle would be the thickness of the deck crown,  At the tops of the frames.  At the side, the thickness would feather to zero.  The wider this pseudo beam the happier you will be.

This crowned deck would be done using- a shim that is an arc, actually,  The old How To Build A Ship Model books  show to get an arc or an ellipse over a distance.

 

For the deck - to avoid creating a cartoon by over doing it: 

A touch of walnut aqueous stain or walnut acrylic paint added to the PVA on the plank edges should give you a scale appropriate caulking seam. 

No trunnels.  

Study up in planking butt shifts. 

A 4 butt shift with just a hint of a seam - not a wide -poke you in the eye bowling alley gutter seam. 

The grain makes doing a scratch for a cross plank seam difficult to pull off.   I wonder if one of those ultra thin saws made from a razor blade would leave an even channel  - not deep and filled with walnut PVA would do it?

[Jim in KC]

I'm a newbie building n 1850 Swift pilot build.  The deck definitely has a camber.  Which leads to a related question. My kit calls for waterways - thin strips that run along the inside of the bulwarks.  I'm not sure what these waterways are or were for in real life.  Obviously it has something to do with draining water off the deck through the scuppers.  But the deck is already rounded and the scuppers will be placed at the lowest point on the deck, so water should drain anyway.  I was on a destroyer in the Navy - the weather decks were indeed cambered and water drained naturally through the scuppers - I don't remember it needing anything else.  Can anyone enlighten me?

[wefalck]

Well, the construction of wooden ships is rather different from modern warships and again what is done on some kits is different from how things were done on a real ship. 

 

The design of the 'waterways' and related planks can be something quite complex on larger ships and something relatively simple on smaller ones. In general, it is a plank more or less twice the thickness of the deck-planks that runs inside along the frames or stanchions. It acts as longitudinal stiffener at deck-level and the corner to the lower planks provides a gutter from which scuppers, lead pipes, would lead the water outside. Much of the water on small ship might actually be shed through a gap between the lowest bulwark plank and the waterways/filler pieces (see below). Freeing ports with swinging flaps came in use only later.

 

I have looked on the Web for an illustration that might be close to the situation of your model, but only found one with two decks, but it shows the principle:

 

In your case there may not be the plank called 'plank-sheer' in the above drawing, but only filler pieces between the stanchions.

 

So you would need to run that strip of wood inside the frames/stanchions and will the space between the stanchions up to the level of the waterway.

 

Hope that is reasonably clear

 

 

 

 

 

[Jim in KC]

Thanks for the information - I think I get it.  Since the waterway planks run inside the stanchions, it channels water to the scuppers, preventing it from accumulating between the stanchions, right?

[wefalck]

In principle yes.

[Jim in KC]

Thanks again for the information.  I have another question.  My kit has the waterways running unbroken from the stem to the stern.  It seems to me that the waterways should be gapped at the scuppers so water can run out there.  In looking at the completed logs for this build, two did gap the waterways at the scuppers while 3 or 4 did not.  What do you think?

 

By the way, I really appreciate you taking the time for this.

[wefalck]

No, they were running all the way through because they are, as I said earlier, structural parts that strengthen the hull at deck level.

 

The scuppers are lead or copper pipes of around 2" internal diameter that lead from the corner below deck and the outboard, probably somewhere above the wale, say 1 to 1.5' below deck level.

 

There would be different ways of simulating these scuppers:

- The simples way would be to drill an appropriately sized hole, chamfer it a bit with a burr and then turn a soft pencil in the hole to simulate the lead - good for small scales.

- Drill hole as before and insert a piece of cored solder wire from both ends; the core has to be bored out with an appropriately sized drill; flare out the ends.

- There are small copper sleeves on the market that would be crimped over electrical wire instead of soldering; use instead of the solder wire; they can be found in electronics shops.

 

[Jim in KC]

Thanks again - I really appreciate the information. So they are there for structural strengthening as well as for shedding water, and to have a gap would undercut the strengthening function..