After a great meeting in Amsterdam it was back into the workshop and work on the keelsom.
The size of the keelsom I have taken from the E81 Samuel wreck, which is with 95 Amsterdam foot the same lenght as my fluyt ship.
The keelsom width is 1 3/4 ft and a thickness of 2/3 ft.
It is composed of three parts, the aft part which is largest and contains two holes which are to my opinion for the pumps and the main mast foot. It connects via a scarph joint to the middle part and the curved bow piece.
See below the archeological drawing of these.
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After preparing proper size strips the scarph joints are milled.
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Until a proper fit is created.
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In the long aft piece a mast step is created, it is situated in the center of the ship half way between bow and stern.
I have used again the E81 as an example.
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And the original on Samuel.
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At the bottom I have created a drain to avoid rot to the mast and keelsom. I have taken this from another wreck, the K47-II which was a freighter between 30-35 mtr from early 1700. It's zaathout is very comparable in size. See below the maststep picture from the archeological report of this wreck which is in a farm field in the Noord Oost polder., yes here in the Netherlands there are quite some shipwrecks in fields which were previously sea bottom
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A next study was on the fastening of the construction.
I expected before the zaathout (keelsom) was fitted the liggers (floors) would be fixed to the keel. I had misinterpretated the paper "double dutch solutions in flush planked shipbuilding" of Thijs Maarleveld about the SO 1 wreck where he states
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The liggers were only nailed on the edges to the planking for temporary fitting. Then they were treenailed to the planks, so still no fixing to the keel.
Only after fitting the zaathout bolts were driven into the construction.
See below again a picture of E81 here the zaathout, ligger and keel are shown with two bolts attaching the zaathout to the ligger. There seems to be no connection between ligger and keel which looks odd to me as this really weakens the construction.
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Maarleveld writes in his SO 1 paper
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This means minimum 1 bolt in each ligger from the zaathout. Every second ligger the bolt goes through the ligger into the keel.
On E81 there are two bolts in every ligger, see the drawing at the top and the picture below.
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To create a sturdy construction I opted for 2 bolts conform E81 and of these two bolt 1 goes through the ligger into the keel. PS and SB bolt changes every second ligger to go into the keel.
See the nail arrangement on one side below. With long and short bolts.
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After fitting the center zaathout.
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The forward part is fitted on top. The edges of the scarphs are nailed additionally to the bolts.
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The whole zaathout is fitted, the backbone of the ship.
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The mast step is nailed with it mast angle trim adjustment on the rear.
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Next time we start the scheerstrook.