Saturday, 18 January 2014

Installing Keel

Once I had cleared my thinking about whether to fibreglass the garboards and whether to install keel on while the hull was turned upside down, the time for action had come!

I called John Brooks. the designer of the Somes Sound 121/2 who explained the pros and cons of fiberglassing the hull - his view was that epoxy alone was a poor option and that if I wanted to use epoxy on the hull, I should also fibreglass it.  But when I thought further of how much the garboards are protected from abrasion by the protrusion of the lead keel, it became obvious that this was a wasted effort.  So I decided (again!) to stay with the marine paint and reply upon the quality sapele marine ply for durability....phew!!!

Next decision was whether to install the keel before turning the hull rightside up.  I was keen to pursue this option for reasons of access to final fairing of the keel into the hull and also since I have so little space in my workshop.  John felt that armed with the right lifting tackle the hull should be well able to withstand the forces of turning.  I then emailed Dave in SFO who also build a beautiful SS12.5 and pioneered turning the hull with the lead keel on, and he thought that my approach would work fine. Serendipity played its part when my neighbour and firewood supplier John gave me three large strong ratchet straps which were surplus to his requirements.   So that settled that!

I cut countersink holes in the keel with a forstner bit which was a little undersized but I was pleasantly surprised how well a straight bit in my router widened out the hole and gave a clean flat base.

Armed with these insights, Brian and I got stuck into fitting the lead keel.  I had repositioned the hull onto 4 cross timber to spread the additional load on the hull.  Also I coated the insight of the slot in the lead keel with epoxy to ensure that the surface wouldn't wear on the centreboard.

Fitting the keel  was not as straightforward as I had thought, as I had some difficult getting the bronze 1/2" bar down fully.   I had drilled the keel and keelson with a 12mm auger bit and thought that the slightly snug fit would be to my advantage however,  I should have really welded the top nut (or epoxied it beforehand) because relying on double nutting to screw the rod down only allowed me to go so far. I had to cut a a slot in the top of the rod to screw it down the final inch with a large screwdriver.  Panic set it as we realized the task was taking longer than anticipated as we wondered if the epoxy would kick before we got all finally bolted down.  We needn't have worried, but it was a close thing!!

Got to finish up by saying thanks to Brian and all contributors (Dave, John et al) who advised me so well on the process.  It seems like a real milestone has been accomplished!

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