Tag Archives: Systems

Fitness for Use

One of the underlying concepts of “Quality” is fitness for use. A 2×4 makes a bad baseball bat but a quality wall frame. A Louisville Slugger makes a quality bat but a bad wall frame. In our case, a fiberglass RIB didn’t make for a quality dinghy experience. Continue reading

Cruising is ultimately about…

Cruising is ultimately about individuals accepting accountability for their own choices. You’ll see that comment in our disclaimer. In a recent comment dialog on Attainable Adventure Cruising, the subject of inflatable life-jackets has received a lot of useful exploration. In the course of participating, I started rethinking the issue of “choices.” With equipment in mind, there are:

  • Caveat Emptor–you are on your own with respect to what the market provides.
  • Lightly guided/constrained choice–government or private groups assist through testing (UL, etc), and specification (USCG, SAE, IEEE, etc).
  • Tightly guided/constrained choice–the government defines the range of choice, but no choice remains an option (EPIRBs).
  • Quod est Lex — it is the law — government defines the range of choice and enforces it with penalties (no choice option only available to scoff-laws).

When making choices, humans tend to fall between two extremes with a peak in the middle.  Near zero on the axis is how little can I do to meet the most probable need (called sufficing). On the far end is minimizing one’s maximum regret (sort of a belt + suspenders/braces + helium balloon approach.)  Both of these ends tend to be risk tolerance constrained choices.

The middle causes the doubt. The middle tends to be a muddle of the entrepreneurial “new thing” and the enduring “good enough for my Da/Ma, good enough for me.”

Three things to remember when navigating this muddle.

  • Statistically speaking, cruising involves a small, heterogeneous sample set with high anecdotal content (relative to automobiles & airlines for example). Because anecdotes tend to be more interesting than data, we tend to listen to the best stories rather than look at the data all the way back to its accumulation rules.
  • Coincidence and Causation frequently sleep in separate bunks. Look for the confounding variable. One can often drill a very shallow well to get a gusher of “not so fast.” Because there are more influences on the outcome than are being reported or collected, our minds tend to fill in the blanks according to our pre-existing biases. The most frequent error is the apples and oranges fallacy.
  • A product or a service sits on the tip of a pyramid. Its corners are business reality of the provider/market, provider product/service focus, endurability of the support infrastructure, and government involvement. Because we are bombarded with new, New, NEW, we tend to be herded in the direction of non-durable products/suppliers. & Because the current business environment favors consolidation, many of the market’s suppliers are diluting their focus.

Consistent with the disclaimer, I wouldn’t even attempt to suggest an approach, but I will say:

  1. If a highly hyped product has no statistics, or they won’t share them, we walk away–if we are going to be someone’s market development experiment, we have to include early/frequent product/service failure as an acceptable outcome.
  2. If the statistics jump to a connection between widely separated or potentially confounded data, we ask to see more. If more isn’t available, we often loop back to #1 above.
  3. For any product that may require service or spares, we tend to look for suppliers who have a high probability of survival. We would rather have fewer features and benefits in favor of endurance between retrofit, than smokin’ hot performance that can’t be fixed or supplied or serviced should the need arise.
  4. Finally, we believe it best to buy from suppliers who have more than a business commitment to their product. Usually, that can only be determined by a visit to the company. (Boat Shows are Shows, not necessarily Tells.)

Water, Water Everywhere and every drop is priced

Watermaker.

That’s what I started out as. My 1973 masters thesis was on a specialized (inexpensive, industrially threatening) form of seawater desalination that could turn ocean bordered deserts green. Too bad a key component was labelled unsafe for humans for political reasons. Today, the technology hasn’t advanced much. True, we have micro-processors to control things and better high pressure pumps, but if watermakers were on the computer learning curve, we would all pick one up on the way home from work.

They aren’t, so I have thought a lot about whether we can justify the expense and whether we want to take on another thing to maintain. And as is my wont, I did my thinking with calculator/spreadsheet in hand.

I can’t make buying a watermaker make sense.

If we planned to circumnavigate; if we planned to really hang out in rain impoverished places weeks from anywhere else; if we didn’t have 165 gallons of tankage maybe I could. But I can’t.

We can make 165 gallons last a month. But we like our comforts, so let’s call it two weeks. If we pull into an average marina in the US every two weeks for a one night re-provisioning stop, we would allocate 6.5% of that ~$90 cost to a water fill up. Domestic water on the Chesapeake costs about $3.50 per 1000 gallons. So let’s give the marina a 10x markup to $35 per 1000 gallons or 3.5 cents per gallon or, for our tankage, $5.78 call it $6.00 for water every two weeks.[Keeping in mind this is a pseudo cost buried in the marina overhead. We are going to pay $90 for that night whether we bunker water or not.]

In the Bahamas or further south and east, on that same two-week cycle, in a bad year, we would expect to pay as much as $0.50 per gallon for water, or $82.50 to fill up the tanks in paradise.

For a year this would put us between $540 (as far as the Bahamas) and $920 (down to Grenada) for water. That’s an average of $730/year.

The watermaker we liked best was $4635 discounted. Its power appetite could be serviced by the solar panels. In clean water it would only have to be operated 1.9 hours daily over two weeks to keep up with nominal consumption. [I say nominal because everyone we have talked to with a watermaker has watched their consumption go up as a result of having a source of supply.]

However…

It requires about $150 in supplies a year (that buying water doesn’t). So our net effective cost of water per year becomes $580. This divided into the price of the watermaker tells me it would take eight years to break even.

If we were to be cruising for eight years, I think we could safely assume the equipment would have no residual value. I think we can also safely assume we would have spent considerable hours devoting angst and attention to a complex piece of high pressure plumbing likely to become troublesome just when needed.

Frankly, we can use the storage space and be happier. Also, the whole shebang weighs in at about the same as 9 gallons of fresh water — 4.5 days for us to find a source of supply…

Solar Sans Insolance

The system is up and generating amps. But not very many thanks to the overcast. There are a few finishing touches required but those can wait till spring.  Now to begin monitoring performance…

Solar p.r..o…g….r…..e……s…….s

As with all modifications, this one has been a few steps forward and a few back. Fabricating the plates to support the panels and the wiring went fairly smoothly, and I must recommend Online Metals.com. The pieces I ordered came quickly and precisely cut so that I could focus on fabrication rather than clean up. It was very pleasant to have each plate fit as it should after having mass drilled and trimmed the six of them.

Of course, the plate-clamp arrangement for the forward and aft panels had to be custom fit on the boat with the panels in place. This was not easy, and the heat reflected from the panels and the dark blue Sunbrella Bimini, made work between 1300 and 1700 unwise. So this relatively straight forward task took me the better part of two and a half days.*

The pictures show the results. But now, it all has to be disconnected (though not removed) to do the wiring properly. I still believe we will be off-grid by the time we winterize, and truly hope to get at least a few days under sail with the panels in place so I can understand any further reinforcement issues with the frame. My fun meter is still in a good spot, but the $$ meter continues to climb beyond my initial estimate.

*In 94°F weather, the underside of the exposed Sunbrella was 146°F.  In the area shaded by the solar panels it was 109°F. While still warm, this will help with cockpit temps.  I have some foil and bubble insulation I have been thinking about sewing into canvas packets we can put under the heated Sunbrella to further reduce temps. It’s not a high priority…

Panel Supports Complete, but not without a fight

To carry the weight of the panels aft (to prevent “pumping” action in a seaway, I replaced the strap tie-downs for the bimini with 1″ stainless support tubes.  I put them in the plane defined by the backstays to reduce visual impact.  They also appear to provide a way to support the overhanging portion of the aft panel and with no real impediment to tilting the panels when in a marina.

The fight?  The set screws provided with the fittings are metric threads but require an SAE Allen wrench and have an SAE diameter.  I’m becoming well known in the new hardware store in Deale.