Post by tromp on Jan 26, 2017 19:13:34 GMT
Well, it has been quiet here recently which doesn't mean I've turned by back on the discussion, I've been busy doing further research and I can say that I have come across some interesting points that might help to shed more light on the subject. I have received Wendy van Duivenvoorde's remarkable book "Dutch East India Company Shipbuilding" and she too raises interesting points about the "Vlakbouw" method used in the northern part of the Netherlands till early in the 18th century. As Miss van Duivenvoorde works in Australia, it is not surprising that her work concentrates on early 17th century shipbuilding, the Batavia in particular. There are nice scale drawings in her book showing different layers of interior and exterior hull planking.
We can see the gunport is perfectly square. Here's a view of the hull interior:
I have rotated the images slightly so they show the sheer of the hull more or less correctly. Looking at the interior view we can see the frames are tilted. There are also views of the gunport showing that the gunport lid is indeed perfectly square and not diamond shaped or rhomboidal or anything like that.
It has been argued that by 1660-70 when the Hohenzollernmodel was built the vlakbouw method of shipbuilding was no longer used, instead had been taken over by the frame-first method. Looking at the fact that Nicolaes Witsen published his work in 1671 in Amsterdam to me it seems very unlikely that he did so describing shipbuilding technique that was no longer used in that area. Van Ijk wrote in the 1690s that parts of the northern states were still using the vlakbouw approach. Miss van Duivenvoorde wrote that the fame-first method had taken over completely early in the 18th century. that would be 40 - 50 years after the Hohenzollernmodel was built.
It has been claimed here that the Den Helder wreck proves that by that time the frames were not tilted even on a Vlak-first built ship. What is left of the Den Helder wreck is mainly the hull beneath the waterline and I have to say it shows a striking similarity with the Vasa. Particularly around the stern. I have flipped this picture here to show you what I mean:
Now compare this with the iron-bolt pattern plan that Fred posted a while ago:
The similarities in the angle of the frames are stunning! Both ships were built in the Vlakbouw method and the frames beneath the waterline are stunningly identical. The tilt in the frames in Vasa's hull begins way higher up than what can be seen here. As the Den Helder wreck was also Vlakbuilt I have every reason to believe the same happened with the long since gone frames of the Den Helder wreck. I conclude that at least to me there is no archaeological evidence for frames ever being as upright as they were in the frame-first building method. Archaeological evidence we have from the Vasa, Batavia and most likely SO1 shows us that all ship built in the Vlakbouw method had tilted frames. I see exactly the same in photographs of the Hohenzollernmodel. If that model was built in the 1660-70s it was also built Vlak-first and the frames were certainly tilted. Just as I can see them in the pictures of the model.