Agile Boatbuilding

Agile Boatbuilders at work on a WACKY LASSIE
by Fritz Funk

Numquam ponenda est pluralitas sine necessitate.
    [Plurality must never be posited without necessity].

- Occam's Razor from William of Ockham 
 

Entities must not be multiplied beyond necessity.

- Occam's Razor as put by John Punch of Cork


KISS.
   [Keep It Simple, Sailor].

- Occam's Razor, razored by ???


Agile Boatbuilding 

As you may have noticed, I'm  a sucker for rules-of-thumb. 

The best of them are pithy and mnemonic, like KISS. The kind of thing you don't have to scratch your head over, yet which remind you to get back in the groove from wherever temptation has led. When it's a list, it's the kind of thing that every item you remember is going to advance your cause.

Jeremy Ulstad is a boat rat / renaissance guy with a toe dipped in the world of Information Technology (his blog). There, he encountered the Agile software development concept, which he adapted to boatbuilding:

Agile Boatbuilding:

1. Make it Cheap
2. Make it Fast
3. Make it Work
4. Make it Right

This brief checklist will take anyone a long way!

Let's take it again, with a little commentary:

1. Make it Cheap - Economy is a make-or-break factor, for most of us, especially we dreamers who are looking toward a DIY launch into the fringeways of the the world.
   
   Cheap means money, of course, but more broadly, it implies life energy... the time and energy we put into earning money, spending money on things, assembling things into dreams. Just designing the durn things and counting the nails can be draining.
   
   Make it Cheap!
   
   
2. Make it Fast - As St. Larry the Cable Guy says, Git 'er done!
   
   A bane of the DIY builder is getting bogged down in detail. Ambitious shapes, complex interiors, needless gew-gaws and gimcracks... finish! How many boats have foundered before launch on the reefs of Bristol Fashion?
   
   It's the world we want to experience. Our boats are but means to glory. Don't get bogged in trivia...
   
   Make it Fast!
   
   
3. Make it Work - None of the above means we can avoid the bottom line... stuff has to work. Our lives depend on it. Sails have to go up and come down. Anchors set and retrieve. People in, water out.
   
   Simple, well planned, robust construction is the key. Fail-safer approaches. Simple solutions for simple tasks.
   
   Make it Work!
   
   
4. Make it Right - By now, we've checked off one through three, and likely launched. This stage is the long, slow, delicious rest-of-our lives stage.
   
   Field testing takes place in the field. Sea-trials, and then voyaging. Not till then will we be able to fully assess, address and debrief our solutions improving as we go. Getting into the field is the vital step. Go forth and...
   
   Make it Right!

And a last word for the road... one of the Agile core concepts is respond to change  rather than slavishly follow a rigid plan.

Not bad advice for any voyage!

Diet for a Small Boat

Complimentarity for Complete Proteins
See Diet for a Small Planet by FM Lappe

We're not just what we eat, we're how we eat.


Diet for a Small Boat

Okay, not so much a diet as a handful of strategies for feeding oneself on a shoestring.

A lot of the info available for self-sufficiency focuses on land-based homesteads. Horti- and agriculture, often coupled with animal husbandry techniques don't translate as well to seasteading. 

Our distinguishing characteristic, as cruisers, is our mobility. We're not tied to any particular piece of land, but have access to a range of resources. We want, therefore, strategies that allow us to feed along the way. We want to avoid, or at least minimize those which tie us to a particular time, place or economy.

The following are a number of strategies that we're doing, dabbled in, or hope to try. Like most things in our life, it's a work in progress. You'll note that some are diametrically opposed to others. What they have in common is the promise of easing us out of the consumer economy, and toward a more subsistant lifestyle.


Guiding Philosophies

• Nomadics -- Gotta eat and run!
• Wildivoracious -- Eat wild, when possible.
• Locovoracious -- Eat local, when possible.
• Opportunivoracious -- Eat what presents itself.
• Omnivoracious -- Broaden the palette.
• Neo-Primitivism -- Do what can be done by hand.

Approaches

• Neo-Primitive aka Paleolithic Diet -- Fewer, high-quality carbohydrates and more proteins.
• Vegetarian -- Potentially more energy efficient by orders of magnitude.
• Vegan -- See New Age of Sail by Dmitry Orlov.
• Raw Foods -- As adherents ask, "What's so different about humans, among all other animals on earth, that we require cooked food?"

Food Sources

• Gathering (Wild)
• Gleaning (Fringe)
• Fish, Game and Others
• Guerrilla Gardening
• On-Board Gardening
• Barter -- Includes barter for 'money'.

Enhancement

• Fermentation -- See Wild Fermentation by SE Katz.
• Protein Complimentarity -- 2 part grains : 1 part legumes (and other combos).
• Sprouting

Preservation

• Drying -- For the weight-conscious cruiser!
• Pickling
• Brining
• Smoking
• Canning

Fuel

• Biomass -- Wood, peat, etc..
• Biofuels -- Let's say, liquid fuels processed from biomass.
• Solar -- The gift that keeps giving.

*****

We've tried all of these, and most of them have become staple approaches. 

They're easy, fun and tasty. Each of them takes us one step further afield, lets us stay out longer, and reduces our dependency on the monetary economy. They help tie us into local networks of gardeners, fisherfolk, home cooks and friends at large.

Food is something we all need and love...

Why not make the most of it?

Inside Steering: Get Out of the Rain, Silly!

Click on image for unobstructed view.

Get out of the rain, Silly!
-- Mom



Inside Steering

Despite years of good advice from Mom, I spent years sitting in the cockpit, at the tiller, in the rain. Now that I'm a nominal grown-up, I tend to apply a stronger term to myself than 'Silly'.

Pure laziness. One of our mentors showed us the general principal during our first year afloat. When I finally got around to setting it up a couple of years ago, it took all of an hour. 

Silly.

The basic principle is that a single line pulls against springy tension supplied by the opposed bungee. When relaxed, the tiller is pulled hard over, toward that bungee. When tensioned, it can be fixed anywhere, all the way to hard-over on the pull side. Given this range, we can perform any (steering) maneuver from shelter.

Loops at the tiller cleat (or ball... see tips, below) are very quick to engage and disengage. Thus you can kick the system 'out of gear' at a moment's notice.

The bungee in the pull line acts merely as a shock absorber.

Less friction in the system makes the pull lighter, and fine tuning easier. 

We use a caribiner on a grommet at the pull-side corner post, fairleads and a copper plumbing elbow glued in place as a bulkhead through-lead (angle it slightly upwards, inboard to keep rain out... it can be corked for extremes or winter storage). These choices mean we have to turn and face aft to pull comfortably (easing out is easy). Consider reducing friction (see Tips, below).

*****

As a bonus, a slight variation converts it to a lashing system:

The long bungee can be replaced by a line with an eye-splice (loop) in one end. Loop goes over the tiller cleat. The tail rounds the corner post and affixes, mid-line, with a rolling hitch (Scouts call this a 'taut-line hitch'). This can be adjusted to fine tune the lashing position.

The pull line is set up a bit 'up' (to windward) from center balance position, and the rolling hitch is adjusted to pull to balance.

So lashed, SLACKTIDE will sail herself for hours on all points, so long as waves are relatively small. Then we have to babysit the tiller for the occasional deviation, when we're kicked out of balance (lashing at a balance point isn't 'self-steering'). Just slip off one or both loops, adjust course and reset.

KISS, cheap and reliable enough!



*****

CAUTION: The boat may be steering herself, but she's NOT watching where she's going! That's still our job! Keep an adequate lookout at all times.

Tips:

• Substitute blocks or HMD for reduced friction. If you want to get tricky, a wheel or lever at the inside station can supply mechanical advantage.
  
• Substitute a bungee with ball termination for tiller cleat loops on long bungee and lashing lines... tension can be micro-managed by wraps of this line, anchoring ball under nearest horn of cleat. None to a few turns covers quite a range in small, half-turn steps.
•  Make sure that easy seating, adjacent to the tiller is possible... this may require elevating the tiller, slightly, to let lines clear your lap. Installation will vary according to cockpit layout.
• Lashing may not work as well for boats with fin keels... the problem is low tracking. Consider a drogue to enhance track steady, and whether it's worth it... another system may be advisable.
• Splicing bungee to line is tough going... seizing with small stuff works well and looks salty.
• Where possible, run the pull line as much out-of-the-way (close to walls or corners) as is feasible... don't want to trip over it, and a line on a deck can roll and pitch you.

Cruising Mind

Three Worlds
by M.C. Escher

Ah, for just one time I would take the Northwest Passage
To find the hand of Franklin reaching for the Beaufort Sea.
Tracing one warm line through a land so wide and savage,
And make a Northwest Passage to the sea!

-- From Northwest Passage by Stan Rogers



Cruising Mind

For a third of century, now, Anke and I have been tracing a convoluted line across our home waters of SouthEast Alaska in small, engine-free sailboats.

When the wind is fair, we reach or run down the long, straits, fjords and sounds, usually close along shorelines. Marvelling at the detail sweeping by, unfolding mile after mile. Seldom pausing to touch and taste.

With the wind against us, we zig and we zag. Long tack out on long tack in, touching close only at the inshore turns. We console ourselves with the long view. The open and close of mountain, valley and lanes of the sea. Drinking in sweeping transitions from abyss, up the timbered slopes to snowy scapes, each as perfect and aloof as the other.

And when the wind fails, we creep along, exploring every crook and crevice. Getting to know the barnacles by name. Rowing ashore to investigate any prickle of interest.

The world spills in through our senses, writing itself into the very annals of our minds.

Our minds become a chart, of sorts. 

One composed of the myriad points of contact with specific places along the coast. Profiles of headlands. Lines of sight and their relative motions. Currents and plants and scent and the look of stone. The play of light and shadow as seasons roll, one into the next.

Memories and mind connect each point of contact. Fill in the gaps with imagination and experience. Project beyond in surmise and speculation. Weave each lone word into a story, or better, a yarn.

Like a ball of yarn in the labyrinth, our minds - as much as any paper chart - guide us where we will.

Tracing one warm line through a land so wide and savage...

The land is not so savage, any more, though plenty enough so to curtail the lives of those unwary  or unlucky. And wide as ever. There is plenty of white, uncharted space -- terra and mara incognito -- in our minds' chart.

As we sail on, will our minds fill until they reflect our world perfectly? The multi-layered boundary between our selves and our world dissolve?

Until, one day, we are as still... as at one... as fully immersed as that fish in a'swim Three Worlds?

A Short Review of Traditional Sailing Box Barges (Scows)

Easy to improve on these lines... or is it?

A Short Review of Traditional Sailing Box Barges

Box Barges (Scows) aren't new kids on the block. After the log, dugout and raft... barge.

For most of that span, they've been rigged for sail. And not just until folks knew better. Right up into the last of the Age of Sail, outlasting the clippers.

Take a look at the picture of the barge-ketch, above. It's likely a Great Lakes boat from near the late 1800s or early 1900s. She likely hauled freight in competition with any number of Curvy Dogs serving the same ports. Not only did she hold her own, but a whole fleet of her sisters were thriving in the same waters.

But look at those lines! Her steep, knuckled entry and exit are close to poor as can be. And this in a day when quality wood and skilled labor were in relative abundance. 

An abrupt entry means plowing water. An abrupt exit means a turbulent (draggy) release.

The economic advantages she gains through simple construction and maximum capacity on given footprint must have been enormous to outweigh making the slightest concession to speed! Hullwise, anyway... that rig looks speedy to me!

Still, if you ask me, those knuckled ends strike me as hard or harder to build than curves. And they wouldn't give up that much displacement. And with that bowsprit, lengthwise port costs couldn't have been a huge factor.

So it's a bit of a mystery that they built them so abrupt. Did they need to make the most of the deadflat for, say, stowing lumber?

ALMA, getting slipperier.

Here's ALMA, a San Fransisco Bay Hay Scow. Similar coasters carried Russian ice cut from Swan Lake, New Archangel (now Sitka, Alaska) to SF... no small feat, today... that's still one rugged coast!

 Lines are getting easier (longer and less abrupt)... more bottom curve and angle at both ends. 

We note that the exit is easier than the entry. Curious. Is this an evolved, hydrodynamically efficient arrangement? Or is it some holdover from the old (discredited) cod's head / mackerel's tail rule-of-thumb?

Let's establish a convention for talking about the proportions of aft curve : deadflat : fwd curve... looking at ALMA, I'm going to guess about 1/4 : 5/8  : 1/8 of LOD (Length On Deck).

Civil War era blockade runner
(replica built by Crystal River Boat Builders)

 
Here's one built to run wartime blockades... in other words, didn't want to be loitering around. I'll assume she wasn't slow, nor does she look it.

But she was also running supplies to ravenous armies, and likely slipping up sloughs and creeks to get out of sight. Of course she's a scow!

Proportions look to be about 1/3 : 1/3 : 1/3 (see also other pics of SPIRIT on related sites).

For the first time, we see an easy entry. Did this contribute to speed?

ANNA, looking sleek!

ANNA is another who's sisters were born in the Great Lakes. No plodder, she, though... This type had a reputation for speed among fast boats.


ANNA looks to be about 1/2 : 1/4 : 1/4... hard to tell... her aft curve is so long and easy that it could be anywhere from 1/3 to 1/2?

Here again, the entry is more abrupt than the exit, though it didn't seem to tarnish her reputation. 


*****

So the question remains... is the blunt-ish bow fast enough to make no never-mind? Is the easy exit and release the real key to increased speed? Or is it an artifact of having aft cockpit and quarters aft, rather than heavy cargo? Or both?

Fortunately, we see 'good enough' anywhere in the range. 

My guess is that a moderate curve forward gives good performance, rises well to waves and pounds less in most conditions, while an easy exit lets the hull pick up and go. Other considerations can push or pull the shape this way or that without undue penalty.


*****

An interesting aspect of traditional boats is that they were seldom designed, per se, but rather evolved.  Any more efficient variant, relative to the job at hand, tended to get copied.

Today, we tend to think in terms of speed or windward ability as the prime criteria for comparisons. But historically, at least among working craft, economy was paramount.

And economy is a gestalt of factors.

Even our first example was economical. We may no longer remember the reasons, but those who built and worked those pug-nosed vessels likely knew to the penny where profit lay and where not.

And that gestalt doesn't begin and end with the vessel itself, nor even its interactions with wind and sea. It perfectly reflects the state of supply and demand of its time; personnel, materials, cargoes, markets, competitors... even laws and the ability to enforce them. Of course speed and windward ability factor in, but they don't always have the only, or even the last say.

Our own lives have their own economic considerations. We want the best return on our investment, but 'best' is a fuzzy, nebulous, personal affair. And we're often led to look where our best interests are not, by those who would sell us a load.

We and the vessel we choose - if the relationship is to be a happy one - must also find economic balance.

Box Barge Displacement: Archimedes 101

Plimsoll Lines from the Wider World of Displacement

 Box Barge Displacement: Archimedes 101

Story goes that, as Archimedes eased himself into his bath, the water he displaced ran over the edges and onto the floor. 

Nothing but a mess, for most of us, but Archimedes made a sudden connection; he knew, of course, that the volume of water he displaced was equal to his own, immersed volume. But what was not so obvious; The weight of the water he displaced must equal the weight of his entire self... specs, toupe, false teeth and all!

He got so excited by his discovery that he ran down the streets of Syracuse, buck-nekkid, shouting Eureka!!! Must have been somethin'... we're still talking about it 2000+ years later!

The actual Archimedes principle goes on to state that the floaty force acting on a floating object is equal to the weight of the displaced fluid.

So why do we care?

Well, we live aboard floaty objects. We want to know how much they can carry; how deep their hulls reach into the water; how much freeboard will stick out; how much it will settle if we move our anvil collection aboard; how much sail it takes to drive them; how they will float on their sides or upside-down. These and many other questions are informed by calculating displacement.

It involves a wee bit of math (Eeeeek!), but don't be frightened!!  Curvy Dogs require elaborate calculus, but we - box bargers - need only simple 'rithmetic. [Niener!]


The gist is that we want to convert our underwater (immersed) shape into a simple slab, whose volume is easy to work out. Being square sectioned (slab-sided), and rectilinear in plan view, box barges are already half-way there! One cheap trick is all we need.

Here's a walk through: 

Cheap Trick is close enough for Jazz... 

What we're doing, here, is combining the two wedgy slices at the ends into a single slablet, and adding that to the middle slab over the deadflat. We don't really need to flip one, as seen in step three... it's enough to understand that this is, in effect what we're about.

NOTE: Due to plywood standard dimensions, TriloBoat math is a snap in the Imperial System (feet, inches, eighths and pounds). The following can be done in Metric, but sadly, generates funny numbers and mistakes. So we console ourselves with a pint and work in the yoke of vanished Empire.

A, B and C are all linear distances between points along the waterline. Beam, Draft and Total are dimensional distances (at right angles to one another). When we multiply these together, we end up with Volume in cubic feet (ft3).

Once we have Volume, we multiply it by the weight of water in pounds per cubic foot (lbs/ft3). 

Fresh water weighs about 62.4lbs/ft3. Sea(salt)water is heavier at about 64.3lbs/ft3. A designer would choose one or another based on where the boat is expected to be used. It's not a huge difference, but does add up. The upshot is that the boat will float a little higher in saltwater. [Figures like these can be found in the Pocket Ref or searched for on-line.]

Displacement = Volume x Weight.of.Water / ft3

That's the general picture. Let's try an example from my point of view as designer:

Let's say I draw out a T32x8 on graph paper, for use in salt water. I decide that the draft will be 1ft and draw that in. Next I count squares along the water line, and find that:

A = 5.5ft, B = 16ft and C = 5ft

Total = (A+B)/2 + C
         = (5.5ft+5ft)/2 + 16ft
         = (10.5ft)/2 +16ft
         = 5.25ft  + 16ft
         = 21.25ft

Tell ya the truth, if the ends are this similar (which they usually are in TriloBoats), I'll cheat again and just call the wedges equal, and therefore A and C are too. Since they're the same, we don't have to average them; C simply completes A.So the above simplifies even further:

A = 5ft and B = 16ft
Total = A + B
         = 5ft + 16ft
         = 21ft

The difference between them only rounds a skosh downwards; ultimately, a bit of extra displacement is a pleasant surprise.

So:

Volume = Beam x Draft x Total
              = 8ft x 1ft x 21ft
              = 168ft3

And (I reach for my calculator):

Displacement = Volume x  Weight.of.Water / 1ft3
                         = 172 ft3 x 64.3lbs / 1ft3
                         =  10802.4 lbs                         ... notice that the ft3s cancel out.


Eureka!

This boat displaces about 10800lbs. That is, by Archimedes Principle, how much she'll weigh, fully loaded, including the boat itself, gear, supplies, crew and the dog, when loaded to her Design Water Line (DWL) - the waterline as intended by the designer.

But lo! In the course of time, we tend to accumulate stuff, and each gimcrack and doohickey settles us a little deeper in the water.

For extra credit, let's calculate a displacement related number, Pounds Per Inch of immersion (PPI... somebody, somewhere dropped 'I' for Immersion!). This number is the amount of weight required to lower the vessel one inch deeper in the water. 

Here's the formula for our 32ft box barge:

PPI = DWL x Beam x (1in x 1ft/12in) x Weight.of.Water/ft3

That odd bit in parenthesis is a ratio, which merely converts inch units to foot units (one inch being 1/12th of a linear foot, or about 0.833ft). In our example:

PPI = 26ft x 8ft x 1in x (1ft/12in) x 64.3lbs/1ft3
       = 26ft x 0.833ft x 64.3lbs/1ft3
       = 1392lbs

That's a lot of seashells!





Note: Box barges with high ends load gracefully with weight secured low in the hull. But there are limits, and exceeding them can be deadly. Be aware of them! If in doubt, the Coast Guard is happy to conduct free stability tests for your design or boat.



      

Heat Sinks, Hope Rises

COP (Coefficient of Performance) = Q (Energy Ouput) / P (Power Input)

Heat Sinks, Hope Rises

One winter, chillin' in Sitka Harbors, we noticed one boat that was pumping water, 24/7.

Normally this is a bad sign.  Bilge pump on. Leak. Problems. So we flagged down a Harbor Dude, and wondered if he might not want to contact the owner.

"Oh, yeah", he said, "it's not a bilge pump. He's got some kinda heater going."

Heater??? OMG, it's gotta be a heat pump!!! I started to salivate and haven't stopped.

Later, I ran into the owner on a 20degF day. He confirmed that it was indeed "some kinda heat pump", and that it was keeping his boat at about 60degF. "The equivalent", he said, "of a 1500W heater." (!!!)

So here's the deal. Any mass above 0degKELVIN is a heat sink, seething with kinetic energy. Gaian (liquid) water temps on pelagic-scale heat sinks means there are boatloads of energy out there to 'harvest'.


The notion of extracting heat from a liquid that, should we jump in, might be freaking cold, is counter-intuitive (at least to me). In high school physics I struggled (in vain) against the notion that there is ample heat in a frozen lake to boil a pot of tea. But it's one of those weird and wonderful truths!

The source of this energy is the nuclear-fired Sun. No perpetual motion, folks... when the sun burns out, the free lunch counter is closed. Get over it. Energy is not being produced by the machine, merely extracted from an energy reservoir.

P is the amount of power (energy) invested to harvest  latent energy from the fields of the sea. Q is the amount of energy harvested.

This is analogous to eating a big breakfast and gassing up a chainsaw (P) to cut wood. Burning that wood (releasing its latent energy as Q) returns more heat than you'd get burning the food and gas direct. The food and gas are investments against the energy stored in harvested wood. The Coefficient of Performance (COP) of the whole operation is Q / P. The bigger the COP, the better.

Heat pumps aren't  magic, or even terribly exotic. 

Your 'fridge pumps heat from the masses in its interior, and exhausts heat into its environment. Interior and environment are always tending toward equilibrium (insulation impedes this tendency). Heat pumps use energy to temporarily overpower this tendency. 

Ditto a heat sink.

Heat may be pumped to or from a sink. Air conditioners pump heat from the inside of your home and exhaust it in the atmospheric heat sink. And we actually rely upon oceanic heat sinks for our very lives. No other known planet has open, liquid water on its surface. Think about it!

Commercially available units are 'air conditioners', primarily designed to cool cabin spaces:

Pump seawater in.
Raise it's temperature a few degrees using heat drawn from the boat's interior.
Pump seawater out, warming the environment (heat to heat sink).

Some (the ones that have me a'drool) have a reverse cycle, functioning as a heater:

Pump seawater in.
Lower it's temperature a few degrees, diverting that energy into the interior.
Pump seawater out, cooling the environment (heat from heat sink).

P runs the water pump, the heat pump (which raises or lowers water temperature, using refrigerant gas/fluids for the transfer) and a fan to circulate conditioned air.

Q is the thermal energy transferred to or from the water.

Mind your Ps and Qs... in other words, convert them to common units (Watts is convenient).

COP, or Q / P is a ratio (no units, since they cancel out), which currently approaches three... for every unit of energy invested, we harvest about three units. We could say Q = 3P. Our net gain is about 2P (we double our investment). As any banker will tell you, that's pretty good return!

WEBASTO 5000

One small, commercial unit made by WEBASTO is rated at 5000BTU/hr, pulling 4.4A on 115V. That translates to P = 506W/hr, Q = 1465W/hr, COP = 2.89 and change.

Downsides are, these units are large, spendy and not at all KISS. Those ratings are set for some supposed-to-be-average condition. For those of us who sail in below-average conditions, performance falls. The power draw is high enough to be prohibitive for cruisers off-the-grid.

Still, 'tis early in the game, and technologies are advancing which could lower P and raise Q, increasing COP. Costs should fall with market penetration and economies of scale.

In the near future, I would love to see some of Q converted to electricity and fed back into P... once kick-started, it could run on harvested energy (with correspondingly lower COP). Since the sink is virtually unlimited, there would be no  limit to the system size (aside from practical considerations such as cost and footprint). When not being used as a cooler/heater, it would be in essence a generator.

Hope rises!

NOTE: If our WEBASTO example, once up and running, converted heat to electricity (assuming 100% efficiency), then Q = Q-P, or 959W/hr, free and clear. This could go to heat, charging or output power nearly equivalent to a 1K generator. Inefficiencies will gobble some of this up, but it's better than a kick in the head!




A large-scale implementation is now working at the Marine Science Institute in Juneau, Alaska, The heat it supplies replaces 60,000 gallons of fuel per year! Click here to check it out!

Alaska has other projects underway and online around the state. If we can do it here...