Saturday, January 9, 2010

Haulout part 1

We hauled Diadem at Nanny Cay to replace the thru-hulls. Things went smoothly and backing the boat into the travel lift dock was easier than I thought it would be, with almost a foot to spare on either side!

The boat is lighter than I thought it would be.

We immediately got to work removing all the thru-hulls and seacocks. A thru-hull is a fitting that passes through the hull of the boat to allow fluids to flow into or out. A seacock is a valve attached to a thru-hull. Since these are all located below the waterline, if one should break the boat would immediately begin filling with water. Traditionally these fittings are made of brass, which is strong but can be subject to corrosion in the saltwater environment. Since they are all almost ten years old, it was good time to replace them. The new fittings are made of Marelon, which is a molded glass-reinforced plastic. These are easy to install, strong as metal, and will never corrode. We set up a mobile workbench on the back of Tim's truck to cut the new fittings to size.

Removing a thru-hull is easy if you have the right tools. An angle grinder quickly takes off the bit outside the boat and the decapitated fitting can be pushed thru the hole into the boat. Pretty soon we had a pile of gross useless brass fittings.

Most of the old fittings were in decent shape. You can see the nice yellow brass on the end that was cut off, which means that the thru-hull at that point is OK and not totally corroded even though it looked like it on the outside. But...

...this particular fitting snapped in half when we pushed it into the boat!! Just an inch and a half from where we cut it, the brass was so corroded that pieces of it could easily be broken off with my finger! Below is the same fitting as above, but looking at the part where it broke in half. Note how the brass is red and even green in places. If this fitting had snapped with the boat in the water, there would immediately have been over 100 gallons of sea water per minute filling the boat and no valve to turn it off! Scary thought.

Good thing we got that job taken care of! I am doing a bunch of other projects while the boat is out of the water, such as touching up the bottom paint, rebuilding and greasing the propellers, replacing the corroded keel coolers for the fridge and freezer (tomorrow's job and topic of another blog post), and also getting the carbon-fiber steering wheels professionally refinished. They are looking great!!

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