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by Dan and Jan Ahart
Built-in refrigeration on boats is an interesting challenge in that the corrosive saltwater environment, the unusual shapes of the areas available for refrigerators and constant, if minute, flexing of boat hulls conspire to defeat the best efforts at design and construction. In our case our "refrigerator" is a built-in box with a thick tapered lid on top like those used on ice cream vendors' freezer chests. About two months ago, while cleaning the bilge cover, which serves as the deck (floor) in front of the galley work counter that contains the fridge, I noticed a wet spot just below the access cover on the side of the counter. I removed the access cover to investigate and found some very wet insulation under the fridge box. This was worse than bad news. It meant we had a leak in the fridge and water that accumulates inside the fridge due to condensation was leaking out and into the insulation. We knew we had to tear out the existing fridge and either re-build it or replace it.
Three weeks ago we started the dreaded project. First, we had to tear out the existing box with all its wet insulation. We discovered, like archeologists, that we really had a box within a box. The original box, built-in by the boat manufacturer in 1983, used an old type rigid foam insulation that was only one and one half inches thick. It was probably adequate for the climate in Great Britain, where the boat was built, but in the tropics, it was obviously inadequate. Also, the inside of the original box was some sort of thick material not unlike gelcoat that had been sprayed in. It didn't look very strong. In order to increase the insulation, a previous owner had added two more inches of a different type of foam inside the box, thus reducing its size, but improving its efficiency. The concept was solid, but the follow-through was not. The new box was simply made of sheets of formica that were glued to the new insulation. It looked nice, but the thin formica and the adhesive used to join the corners weren't strong enough to withstand the rigors of cruising. The seams eventually separated allowing water to seep out and into the confines of the original box, which had also developed cracks, and subsequently into the insulation. When the insulation was saturated, it lost a great deal of its insulating capability and moisture began seeping out and onto the bilge covers.
Once all the old wet, moldy and stinky insulation was removed, we cleaned and painted the "hole" in the counter. Next we added a new floor of ¾ inch marine plywood. Then came the fun part. We purchased a 4 x 8 foot by three inches thick sheet of the best urethane foam insulation available. This we cut into pieces in order to provide six inches of insulation on the bottom and three inches on each side and the top. Because of the shape of the space available, there wasn't a single piece of foam that had a square corner. We had to make cardboard templates of the shapes we needed, then cut the foam and shape it by hand to fit. Cutting the foam was like cutting watermelon. Not the rind, the inside. The foam was very lightweight, very easy to damage and could be shaped by hand rubbing. Sounds easy, but the dust that was generated got everywhere and was very difficult to wash off. It took us two long days to shape the six pieces that made the bottom, sides and top of the new box. Before putting them in place for the final time. We lined the "hole" with aluminum foil, shiny side out to reflect any infrared rays. Then lined it with 10 mil plastic sheeting as a moisture barrier. Finally the foam went in. Next, we spent two more days shaping marine plywood to fit the odd shaped walls and floor and top of the box. Then, three more days were spent lining the plywood with three layers of woven fiberglass mat. During the curing period for each layer of fiberglass, we shaped the "lid" for the new box. This was also made of foam and fiberglassed for strength. When all the fiberglass had hardened and was sanded smooth, we painted the inside of the box with an undercoat of two-part epoxy paint and two final coats of two-part polyurethane paint, which dried very hard, white, glossy and looks just like the inside of a refrigerator. The new box is much stronger and hopefully more efficient than the previous boxes and should not leak. The final touch was installing the holding plate evaporator coil and connecting the freon lines to the compressor. All told, about $500 in materials and at least 100 hours of our labor plus $400 to a refrigeration technician for removing the old freon tubing and fabricating new tubing, connections, adding a filter, moisture absorber and new freon. All this cost and effort for a refrigerator that is no more than two cubic feet. Such is the price we pay for our luxuries while cruising. It was fortuitous that we had purchased a book on building refrigerators for boats some three years ago, while we were attending an annual meeting of the Seven Seas Cruising Association. Without the book, we would have been forced to hire all the work done. Now we have bragging rights with other cruisers about how knowledgeable we are in the arcane ways of shipboard refrigeration.
Our second major project while in Trinidad was to have our standing
rigging replaced. The standing rigging is the collective term given to all the
cables and connectors that hold the mast upright and support the jib,
which is the sail on the front of the boat. We had no idea how old our rigging
was, but some of it was nine millimeters in diameter and according to the
rigging specialists from whom we received bids, that size has not been
available for more than 15 years. We replaced it with 10-millimeter wire.
At 41 feet, our boat is not particularly large or complicated, still it
took over 300 feet of stainless steel cable and three dozen expensive
connectors plus several hours labor to remove the old cables one at a time and
replace them. Then they all had to be adjusted properly so as to be tight enough
to do the job, but not so tight as to overstress anything. It is possible to
over-tighten standing rigging to the point that the shape of the boat
actually changes slightly, resulting in hatches that won't close or bilge
covers that cannot be removed. The most complicated phase of the work was
replacing the cable inside the roller furling system for the jib. What
should have been a straightforward job turned out to be very complicated
and required the rigger to take the entire 35-foot long roller to his shop for
dismantling, modification and rebuilding. Our system is rather old and
out of production, so parts that needed to be replaced could not be found.
Therefore some new parts were fabricated and the system modified so
existing, but not quite exact duplicate parts could be installed. We now
have standing rigging we feel we can rely upon for many years to come and
a fridge that is working fine. It is time to fill the fuel tanks, stock up
on provisions and start watching the weather for a good "window' for a voyage
north to Guadalupe and some stops along the way. Stay tuned.