Wednesday, 19 December 2007

Hi Guy's

I have just looked at my last post the spellings terrible probably made worse by bad typing but never mind. Anyway the work shown in these pictures was done around September 2006 the transom and stem had been fitted now the keel was next. The plans show that the keel is 6" by 1" by 18' long. When I had been researching the project I had read in the Gougeon brothers book that you should laminate the keel with some 1/8" marine ply in it to give it some cross grain strength. I had to source this material in metric measurements 25mm to1" so I ordered four 3m by 160mm by 11mm lengths of utile and one 2.5m by 1.2m by 3mm sheet of marine ply. these were to be scarf jointed into three keel planks to be laminated into one 25mm keel 11mm + 3mm + 11mm=25mm.

I used a string line to mark the centre line of the utile planks, I had ordered them planed but they weren't straight. I marked the width of the keel 6" from this centre line and planed the planks to size using the bench as a shooting board. I used the same method to cut the material from the 3mm ply sheet.

The planks and marine ply sheets were joined with scarf joins, I ensured all of the joins were offset to avoid weak points in the keel. I used some shuttering ply and a batten to make a template of the keel for the first three molds where the keel tapers. This showed that the curve was not fair at mold 2 and the tip of the stem. I adjusted this by planing an 1/8" off the top of mold two which gave an extra 1/4" width to the keel there and by using a spokeshave to reduce the with of the stem at the tip by an 1/8" to give a fair line. I took the chance to check the fairness of the first three molds with the stem using a batten and found mold one was 3/16" to wide on both sides so I used a straight edge held to the face of the stem to project a straight line onto mold one which was marked. A flexible batten was used to mark a fair curve through these marks and the mold planed down to this line. This was checked with a batten.

I test fitted an marked each keel plank in place and used the template to rough mark the outline of the keel at the bow. The first plank was then fitted to the mold and bonded at the stem and transom and left to cure. The two remaining planks were bonded in the same way. I again used a batten to check the marked curve on the keel for fairness and block planed the keel to this line.

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