Wednesday, February 27, 2013

What wind generators ought to look like

A recent craigslist ad here in Seattle really caught my eye (it may not be there by the time this gets published, but if you are interested, let me know).  The ad offered a wind generator, but not like any I had ever seen.  The generator was manufactured by BalMar, a well-respected manufacturer of marine alternators and regulators.  And when I say local, I do mean local - BalMar is here in Ballard (I suspect that BalMar is a contraction of 'Ballard Marine').  A web search did not turn up any references to it, so it is apparently out of manufacture, sadly.

Now why was I so intrigued by it?

Well, first, a wind generator would seem to be a natural fit for an alternator manufacturer like BalMar.  And based on our experience with their other products, I'd expect that this thing is bullet-proof.

But more importantly, look at this:


It has self-adjusting variable pitch blades!  See those lead balls?  The faster the hub spins, the more they are thrown out, rotating the blades, changing their pitch.  The movement is resisted by the spring on the axle; adjusting the spring tension adjusts the rate of pitch change with RPM.

Why is this a big deal?  Because whatever pitch is set by the manufacturer of any fixed-pitch design (and that's all of them, I think...  somebody prove me wrong), it is really only optimal for a single wind speed.  And here is the proof of the pudding:  Virtually all current wind generators are just starting to turn at 10 mph.  This one, however, starts to deliver power at 5 mph, and produces 187 amp-hours a day at 12 mph.

And in high winds, it self-feathers to prevent overspeed.  Wow. 

Here is a view of the hub from the side:


As you can see, BalMar has fixed the 'rotor' portion of the alternator to the base plate, meaning that there are no slip rings.  The wiring just attaches directly to the coil.  The actual rotor (it would by the 'stator' in a conventional alternator) consists of a series of permanent magnets embedded in the white rotating hub.  And the hub is provided with fins to generate a flow of cooling air.  BalMar seems to have a well-thought out mature design here.

Huh.  So why aren't all contemporary wind generators derivatives of this design?  Well perhaps because it was sold for over $1000 more than 20 years ago.  In today's market, a $1000 generator would be at the high end.  Twenty years ago? 

Sadly, the adequate is often the enemy of the superior.

Monday, February 25, 2013

$$$

Teak is expensive.  You'll know this if you start looking for it on eBay.  There you'll find sellers offering individual boards, really more as jewelry than as lumber.

Six pieces of teak, 4" x 1/2", 4' long

Those six little pieces of teak, easily carried in one hand were breathtakingly expensive - $173 to be exact.  If you don't have a calculator handy, that works out to $40/net board foot (plus WA state tax).  It's easy to see why modern boat builders have all but abandoned the use of teak.

Eolian was built before the price of teak went thru the roof.  This is both a blessing and a curse.  Blessing because she has a rich, full teak interior.

But that is a curse too.  It's why I had to buy those delicate little boards to make a valance for above her large fixed ports.  With the rest of the interior made of teak, it just wouldn't do to use something else.

And yes, that means a new project is coming...

Friday, February 22, 2013

Where does a song come from?

For some people, the muse is like a friendly roommate, someone who is constantly in conversation with them, who knows them, how they think, what motivates them.  We call these people "musicians".

For me, the muse is more like a crazy uncle who blows into town rarely and unpredictably.  And when he does come it is often at an inconvenient moment - he drops his load and then is gone again - for a long time.

Last nite my muse came while I was asleep.  He gave me a vivid dream, so vivid in fact that it awakened me, of a song in D minor.  But this morning all I can remember is the chords and part of the chorus.  I got out my guitar and firmed it up, and then wrote down what I could remember. 

Maybe he'll stop by again tonite.

Wednesday, February 20, 2013

The value of a bad day



Without darkness, we would not seek light.

 Without sadness, joy would fade to the commonplace.

And after all, why is the high season for Hawaii Dec-Feb?  It is just as wonderfully warm and pleasant there in July, and there are many more flowers in bloom.  Without winter, spring has little value.

The answer is written in the human condition:  we are so adaptable that continuous exposure, even to paradise, soon turns paradise into the norm.  We have internalized it.  We are no longer emotionally stimulated by it.  Paradise, yes.  But boring.

To enjoy a day under sail to its fullest, you should have first spent several days at the dock.

The twentieth day under sail on the trip from Baja to Nuka Hiva is no longer joy, it is drudgery - something to be endured, to be gotten past.  But presuming equal weather and sea conditions, it is the same as the first day out of Baja...  except that the infinite adaptability of the human has internalized all of the good stuff.  Leveled it.  Squelched it.

Ah, but if on days 18 and 19 you have had to make your way thru squalls and big swell all day and all nite, well then day 20 will once again bring a fresh outlook, and joy!

To fully appreciate the joys of cruising, of sailing, of living under sail, you must also have experienced bad days: storms, cold rain, windless calms.  This isn't some kind of weird Calvinism, it is a simple consequence of human adaptability.

Now, this is not to encourage you to go out and purposely find disagreeable conditions.  But when you do encounter them (and you will...),  you should experience them, live them.   And look forward to the blue skies and the 15 kt wind on the beam which will surely follow in days to come.  And because of having lived thru the disagreeable, the skies will be all the bluer, and the bow will slice thru the waves all the more cleanly, gracefully.

In a recent post comment, Petr and Jana referred (thanks guys!) to an article that got me thinking about this;  it does a much better job of describing this human truth than I have.  I encourage you to read it.

And store it away for the next rainy day at anchor.

Monday, February 18, 2013

Baby chickens?

The Internet is an exceedingly strange place.

It is a well-known fact that large numbers of people spend hours every day trolling thru the Internet for pictures of cats and kittens.  I have exactly one post that has a cat picture, and those folks regularly find it.

But for reasons that are completely beyond my understanding, I see a small, steady stream of visitors to this post, looking for "baby chicken photos".


I guess that they will now be coming to this page too, so that by simply recognizing this odd fact,  I am inadvertently increasing the weird traffic.


Wednesday, February 13, 2013

Prototyping

Modern boat design and construction isn't like it used to be.

At the Seattle Boat Show, one of the power boat manufacturers brought in a prototype of a proposed boat. 


It was made up of a series of CNC cut plywood panels, assembled into 4 (or more?) sections, cleverly keyed so that they fit together without any possibility of misalignment.  As this picture shows, it was possible to walk thru the prototype and get a feel for the interior and exterior spaces.  In some places there were slots machined into the plywood; thin battens were slid into them to give a feel for (for example) how close the overhead would be.

Picture of a picture


It really wasn't possible to get far enough away from the prototype in the show to get a good view from above, so I took a picture of one of the pictures they had on the poster session they had attached to the lower hull.  As it shows, the prototype is fitted out with appliances, seats, controls, etc.  These are all required to get the important 'feel'.  There were even vases with flowers in the staterooms.

And if design changes are called for, it is relatively inexpensive to make them in the CAD program and CNC cut some revised plywood sheets.

When the final design of the prototype is approved, it then serves a second purpose: it becomes the foundation for the male plug from which the female mold will be pulled.  Thin battens are sprung over it and it is glassed in from the outside.  Finally, the plug is carefully faired and polished.  The production female mold is then laid up on the plug.

Computers and computer-driven machining have really made huge differences in the boat fabrication business.

Monday, February 11, 2013

Silicone rubber - Just Say NO

I despise this stuff.

No, that's not a strong enough word - I HATE silicone* rubber.  There, now I feel better.

It's a weak adhesive.

It cannot be sanded.  Or painted.

Nothing sticks to it - not even silicone rubber.  Except dirt.

If you have ever used it on a surface, that surface is almost irretrievably contaminated.  The only certain way to decontaminate a silicone fouled surface is to remove that surface, by sanding, sand blasting, etc.

Eolian's previous owner loved the stuff. 

I can think of only three places on a boat where silicone rubber is called for:
  • There are some plastics that cannot tolerate contact with polysulphide, polyether or polyurethane adhesives or sealants.  Where the manufacturer (notably Beckson, for their ports) requires it, you should use silicone rubber.
  • Lubricating/sealing head hose during assembly.  Apply a coating to the inside of the hose end, carefully heat it with your heat gun until both the main body of the hose and also the stiffening spiral have become soft, and assemble.  Get the hose clamp on while the hose is still soft if you can.
  • Making non-skid rings on the bottom of dishes, serving bowls, etc.  Put down a piece of wax paper, run a bead around the bottom of the dish or bowl and set it on the wax paper.  When the silicone is cured, peel off the wax paper and voilĂ ! - a nonskid dish.
Anywhere else on the boat that you think you might use silicone rubber, polysulphide is probably the correct choice.  You might possibly know polysulphide by its other name: BoatLife Life Calk (yeah, that's how they spell it).  Another choice could be a toned down polyurethane, like 3M-4200  (but stay away from the full-blown stuff - 3M-5200, unless you intend for the installation to be permanent).

Now put down that caulking gun and step away from the boat!


* A little definition is in order.  Silicon (note the absence of the trailing 'e') is a silvery metallic substance - here's a picture of a piece I have on my desk right now:

I should know - I used to work in a manufacturing facility that made the stuff, starting with quartz.  Silicon is the basis for most semiconductors made today, albeit in a more purified form than that chunk on my desk.  It is also dissolved in copper along with other stuff to make silicon bronze.

Silicone is a term that is used to refer to a whole series of compounds based on silicon, in much the same way as the term carbohydrate or hydrocarbon are used to refer to a whole series of compounds based on carbon.  Silicone rubber, silicone grease, silicone oil (in silicone breast implants - not silicon, Heaven forbid!) are silicon compounds.

Sadly, the press seems to use the terms more or less interchangeably, indicating that they have no idea what they are talking about.  But then I repeat myself.






Wednesday, February 6, 2013

The Captain Ron Turn

If you read this blog, you've almost certainly watched Captain Ron.  (If not - what?  Get thee to Netflix!).  One of the most memorable scenes in the movie is when Captain Ron pulls his famous turn while docking at the Saint Hoggs Yacht Club:


We've all dreamed of pulling that off... but I'll wager that very few (if any!) of you dear readers have actually tried it.  Wanna know how?  Our local Sailing magazine, 48° North, posted a Captain Ron Turn howto article in their January issue - it starts on page 73.  Really!

I recommend the article to you (disclaimer:  I haven't tried it yet...).  You never know when you might need to dock at Saint Hoggs...

Monday, February 4, 2013

The mind is a fleeting thing

This morning, I had a great idea for a blog post, but I was not near a computer.

This afternoon, I am near a computer...  but I'll be danged if I can remember the idea.

All that comes to mind now are three concepts that were somehow linked in my mind to the post:
  • The letters "SEM"
  • Pink
  • Small
Which, now that I have written it, seems like a frightening bit of over-sharing.

Now you know how my mind works.  Scary, isn't it?

Saturday, February 2, 2013

Under the weather

The phrase "Under the weather" has been variously attributed to the nautical condition of being too ill to serve on deck, and being sent down below the weather deck. There are other proposed etymologies, but we will disdainfully ignore them since this is a nautical blog.

I am, at the moment, under the weather.

I will appreciate those of you dear readers that stand by me as I work thru this. And the rest of you who abandon me in my time of need? Well, you can go hang.