Geoff with some of his students. The beautiful boat they have built, and are displaying here, is an Iain Oughtred-designed John Dory |
Imagine what sorts of problem-solving issues have been dealt with by the high school students who built this boat |
Another view of the John Dory as she sits in the school foyer, displaying the complexity of work required from a young team - art, engineering, chemistry, arithmetic, manual arts, project management and housekeeping to name a few. |
There are two problems: -
- there is no table-of-offsets;
- Geoff wants to build in glued lapstrake and therefore hopes to minimise reverse curvature in the hull to simplify construction.
An outboard profile and plan view taken from Bertil Anderssons website. Id like to show you the body plan so as to give some indication of the extreme reverse curvature, but I do not want to show material without permission. However, you can take it from me - this is a curvatious boat in the extreme! |
LotsbåtSkum
20½ foot.Length 6190, width 1800 mm.From Kalmarsund. Build in 1910s by Pelle Fräsare in Kalmar, Småland. Completely in oak.
Wondering whether my friend Mr Leedham had handed me a poisoned chalice, I gave it my best shot, and here are the results: -
These are my lines incorporating many changes from the original boat (which I commend to you, with the suggestion that you purchase plans from Bertil Andersson). You can see that cross-sectional reverse curvature has been reduced greatly, particularly amidships and in the run, but that the profile and plan have remained in the spirit of the original. This will be a lighter boat, reflecting her changed construction method, but she retains the character of the original with minimal changes. |
The above renderings show the modified Skum at 6.197m x 1.836m x 0.525m draft ( 20 4" x 6 3" x 1 8-1/2") at a displacedment of 1041kg (2,290 lbs) |
In addition to the lines drawings and off-sets, I have supplied Geof Leedham with a fairly detailed scantlings schedule, which I may publish if there is interest, and if Geoff agrees. He has paid me some money, and I need to be sensible with what I publish in case he refuses to take me for a sail!
Isnt it amazing to see what comes from a scheme to build boats in the desert?
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