A 160-feet VOC-vessel, or…

[abhovi]

I was planning to do a posting about the building of a 160 foot VOC ‘retourschip’ (a ship designed for the Dutch Eastindia Company (VOC), built to make several journeys to and from Asia).
But things do not always turn out the way we want….

Thirty years ago, around 1986, I reconstructed the lines of a 160-foot VOC ship. I used data, found in a book by P. van Dam: Beschreyvinge van de Oostindische Compagnie (Description of the Eastindia Company). He wrote the book in commission of the ‘Heeren XVII’ (the managing directors of the VOC) and published it in 1701. His system was to work his way through the so-called ‘Resoluties’, a sort of reports of the meetings they held twice a year, making important decisions for the Company. In April 1697 their directions for the building of ships were so precise that lines plans could be made.

Why did they stipulate the instructions for their shipyards in so small detail? To understand that you have to know that the Netherlands were not really a country in the 17th century. The area existed of cities, ruling the surrounding territories. In fact, their rich inhabitants ruled the country. In Holland people successfully freed themselves from the dominance of nobility and church. The result was a bunch of cities which were most competitive towards each other. There was no such thing as patriotism or even the notion of any feeling of nationality. Every city looked after its own interests and sometimes they even fought each other.
To manage the country every province sent some of its prominent inhabitants, so-called ‘Staaten’, to The Hague, where they met in the ‘Staaten Generaal’, where important national matters like politics, war and peace were discussed and sometimes even decided.
The VOC was a sort like organisation. To prevent rivalry between the cities in trading Asian products, the Staaten forced the cities to operate the trade together. There were six cities interested in the Asian trade, so representatives of each city would come together twice a year to make the necessary decisions on every aspect of the trade. For instance, the number and sizes of ships per city were established. Shipyards were strictly controlled to prevent them from secretly building too large ships, for that would cause an uneven distribution (and earning) of the spices. Therefore the instructions to the yards needed to be as precise as possible.
The Resolutions of April 1697 were the first where the lines of the ships were stipulated into great detail. Nine frames were measured on six different locations, after which I managed to make the drawings at the kitchen table. (actually there were data for three ‘rates’: 160, 145 and 130 feet long and another one for ‘fluits or hagboats’ of 130 feet, and I worked them all out).



The data strictly followed the shipbuilding rules of those days, so the lines plans I made were not exactly like what we are used to nowadays, but at least they gave a fair impression of the shape of the ships involved.



In 2008 Rob Napier wrote a wonderful book about the restoration of a Dutch VOC model from 1717, the Valkenisse. In it he lists every model of VOC ships that survived the ages. There are about twenty. The oldest was the Prins Willem from 1651, nowadays exhibited in the Rijksmuseum in Amsterdam. Its lines have been taken off and worked out in drawings by my predecessor at the museum, Herman Ketting, who wrote a book about the model. However, there are some doubts about the correctness of the shape, because it might have served other purposes than closely representing the lines of the actual vessel. It was on display in one of the VOC meeting rooms as decoration. The drawings from the 1697 Resoluties are probably the first true depiction of the shape of a VOC ship.

Time to build a model…. I thought.
But as said, my lines plan was not very practical. So my late friend Cor Emke fed it to the computer and his Autocad program spit out a set of modern lines plans.



It was this set of plans I used for my model. Anyone who followed my previous thread about the Dutch fluit knows how the system works: a central spine with frames sled in, all made out of 1 mm thick cardboard. For the central part I used three layers, with additional strips to serve as rabbets for the planking. Not really very complicated and not too impressive either, except for the size on 1/77 scale: over 60 cm.



Then I was stupid enough to compare my hull with the original 1986 drawings and some doubts crept in. Where was amongst others the angled bilge, so prominently present in my drawing?
I ran to the computer to compare my lines with Emke’s ones. It appeared that programs like Autocad (and Delftship for that matter) change the lines they get and turn them into a nice smooth water-friendly shape. And I was stupid enough to forget to compare the results.


To the left the lines of the main frame as it should be, to the right what Delftship made of them.

Then Rene and I compared my old drawing with the locations of the points in the Resolution and again I was not too happy with the results:



The kitchen table appeared not to be the right place to make flawless drawings after all…
So here I am with a 60 centimetres long hull that does not represent the precious lines the Heeren XVII decided on.

I have to think long and careful before I do any more work on this model.
As a sort of self-comforting process I finished the hull of a small ‘smalschip’ which I built lately by way of a finger-exercise. Sails will be added, probably this week.



I'll keep you posted....

[abhovi]

We checked the data from the book by Van Dam again and it seems that the kitchen table was not so bad after all. The diversions are minute:

This is good news for me, but it doesn't get much better, because if we lay the Van Dam drawing over the Autocad drawing by Emke, we see terrible things:

What actually happens is that shipbuilding programs cannot deal with angles. They want to fair the lines, that's what those programs are built for. The transition from bottom to vertical sides were marked by an angle, caused by the change in shape. But Autocad simply disposes the points that don't fit the faired line and replaces them by `better` ones. Thus the hull becomes much rounder and nothing of the original shape is left.

So the conclusion in the end is a bitter one. The hull cannot be corrected and we cannot compare the mathematical data like displacement and stability from this hull with the design the English shipwright Charles Bentam made 45 years later to improve the VOC retourships.

Into each life some rain must fall....

[John Wagenseil]

To what extent was the "boxy" shape of the dutch ships controlled by woodworking methods of the 1700's?
Was it easier or faster or cheaper to build ships with straight sides and abrubt angles rather than a hull with gentler contours?
Also it looks like the contours of the ships as originally built gave a greater hull volume than the autocad revision. Were the ships designed to have a more stable hull with greater displacment and shallower draught than would have been possible with a rounded hull contour?

[abhovi]

The shape is the result of the way the ships were built. They started with the outside planking of the bottom. Next one horizontal floor was placed over the planks, with on both sides a curved part, the first futtock. Then the bilge was planked in the same provisional way. As the floor was flat, the bilge necessarily formed an angle with it.


These ships were built for loading capacity only. Speed was no issue. The stuff they transported was not likely to rot. Draught was another item, because Dutch harbors were shallow. The result was a reasonably stable ship type.

[John Wagenseil]

Originally Posted by abhovi

The shape is the result of the way the ships were built. They started with the outside planking of the bottom. .... .

Thanks, I had not realized that the method of plank first, then fit the internal frame was still used by Dutch ship builders in the 16th c.

[Don Boose]

Another fascinating and enlightening thread. Many thanks for this historical and model craft information.

Don

[Seascape]

Thanks for another great thread. Always look forward to your next posting.

Fred

[abhovi]

Don and Seascape, thank you for your enthusiastic comments on this failure .

And John: the plank first method has been used in the Netherlands up to the introduction of iron ships at the end of the nineteenth century for as far as private shipyards are concerned. The admiralties converted to paper design in the course of the 18th century.

[kndeckhand]

It may be a failure to you, but was a fascinating lesson for the rest of us.

Lyle

[kentyler]

for sharing your failure

I usually learn a lot more from my failures... but its hard to face up to them. Usually I stall for a while before I can build up the energy to keep moving.