As we finish up the exterior of the whole boat now, there’s a short list of ‘modernization modifications’ that should be done because better ideas have come along since this build began nearly 20 years ago.
The six foot bowsprit gets a bobstay from the end of the pole down to the bow of the main hull just above the waterline. We have a stainless steel u-bolt installed to carry this big load as the spinnaker pulls up and forward. But the u-legs are not in line with the force, and the backing plate is measly. Over time, and probably way out on an ocean, this will become trouble.
First we tried removing the fitting, but the epoxy was bonded around the threads so this thing was never coming out. We cut and ground it below the surface and entombed the legs and nuts in the new reinforcements. The new hole was cut about a half inch aft of the point where the hull sides meet to form the bow stem. The tube shape is a 1-1/4″ PVC pipe.
Inside it got a wedge of high density putty that makes a solid wall, then uni fabrics to spread the load, take over for the PVC, and tie the two hull sides together. The access was tough, reaching just far enough inside the watertight crash bulkhead.
Then from the outside we ran strips of uni through the tube and radiated the ends out around the hull about 4″ on both sides of the boat. Three extra layers of uni glass were laid along the pull direction, and that’s what made a bulge on the bow stem just above the new hole height.
Then some ‘finish cloth’ bidirectional 6 oz was added to tie it all together before fairing.
Here’s the work in progress after two fairing passes.
The new bow hole seems plenty strong to better distribute the sails’ force, and no chance of leaky and fatiguing metal. Feels like ten hours well spent.
And here are the photos I mentioned last week about saving some $ on more metal fittings. These are the attachment points for the nets up at the bow, by the anchor. Sort of mini versions of the story above.
The exterior punch list is almost done, and we’ll get back to the cabin build by late next week.
Farrier F36/F39 Ravenswing - Trimaran Sailing 
That definitely seems like 10 hours well spent. Particularly after we saw first hand on Charlie’s boat the amount of force on the bowsprit.
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This post is now at least a season old, did the hole for the bobstay work as intended? It looks as if the uni runs from the hole towards the end of the bowsprit? This would mean compression forces. Why didn’t you choose to run uni around the tube on the inside of the hull, down and aft from the hole?
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Jan, the uni does run as you describe because it’s actually a radial pattern with many 18″ long, one inch wide strips placed through the hole and up each side at all points “around the compass”. It has not been tested, as the boat is still under construction (at the painting stage now).
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