21 Footer – Waterline

The hull had a water line scratched into the planking which we had just assumed was the correct water line. It was only when I decided to just check it for overall length that it dawned on me that its was nowhere near correct! This waterline was from when the motor and lead keel had been fitted, so although parallel it was much deeper in the water that the original design.

When the planking was being replaced, I had removed a copper strip from the forefoot of the keel. I had wondered why is was there and then it came to me, it was marking the 21’ water line at the stem. Checking it with string line and plumb lines it was exact! As this was the first 21’ Footer I had worked on I hadn’t realised how much forward of the 21’ line the bow extended. Leveling the boat and using a laser the correct water line was marked on and below the waterline painted – really starting to look like boat! 

With the undercoat applied to the 21’ water line it is very clear how far behind the stem the boat is trimmed. This water line should be the boat fully ballasted and with all rigging and sails on board but no crew. When racing the effective water line would extend another 3 feet! 

I think another reason I took so long to check the position of the marked water line was that it came as far forward as the kauri planking, which sort of seemed obvious a different colour planking was below the water line!

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