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Anke and I are building our next boat, and writing about it at Access to the net comes and goes, so I'll be writing in fits and spurts.

Please feel free to browse the archives, leave comments where you will and write, and I'll respond as I can.

Fair winds!

Dave and Anke
triloboats swirl gmail daughter com

Tuesday, October 6, 2020

The View from Cold Mountain


Maddy's Camp 
from Cold Mountain, the movie

The mountains look in horror on the madness of the plains.

-- Roger Zelazny

You look at nature. Bird flies somewhere, picks up a seed, shits the seed out, plant grows. Bird's got a job, shit's got a job, seed's got a job. You got a job.

-- Maddy, from Cold Mountain by Charles Frazier

The View from Cold Mountain

Somewhere on the slopes of Cold Mountain, high above the madness of the plains, there lived from a wagon an old woman and her goats.

Or so goes a tale told of another time. Of another bout of madness.

A  refugee from that madness - dying by degrees from a grevious wound - is treated by her skill and kindness. He is set back on his road home with a chance to find and face what awaits him.

Had she lived below, among her fellows, that madness would have swept over her. Maybe she'd have been caught in it, and clamored for the blood of them others. Or maybe she'd have been overwhelmed by it, drowned in its flood or burned by its fire. Or maybe she would have kept her footing, surviving to see the bleak aftermath as the madness settled back to dark mutterings.

What did she feel, looking down from her height. Horror, certainly.

And pity, likely.

Were she younger, at least than she was, she might have felt a tug, too. To do something. To get in there and pull in some direction or another, shoulder-to-shoulder with others. To fight the good fight. To attempt change in whatever direction she felt was right.

But had she descended to the plains, she would have been swept by its madness. The good she was able to do in her story was only possible because she had kept far from the madness of crowds. 

I think it's no small question... what to do in a time of madness?


Picture a river, a canoe upon it and all of us packed in. 

There's supposed to be a waterfall up ahead... stands to reason, but no one has seen it. Some say it's a hoax. Some that it's still many miles on. Some say they can hear it. Some try to warn their fellow passengers.

All the while, the river flows ever faster.

But resources are running low in the canoe, and squabbling for control of them has led to blows. Holes are being punched through the hull, if you can believe it! Few have ears to hear, or time to look up from the fray.

Let's say you are one who hears the thunder of the falls.

Do you do what you can onboard? Do you leap overboard? Do you bother to swim for some kind of shore?

If you stay aboard, surely, you will end up over the falls.

If you leap overboard and do not swim, your journey is over before its time.

But if you leap and swim, you may be ashore to help another from the water.


Leap and swim... this has been our choice. 

Not a moral or courageous choice, nor yet a coward's. Merely one that follows from how we view the sweep of recent history. And I'm talking since agriculture.

Our cold archipelago is our Cold Mountain. Our boat is our wagon. The flora and fauna of these lands and waters our life bearing goats. We are gaining in knowledge and skills to share. And we love it. 

While we know that our bank may too crumble - that we are yet imperiled by the cataract. At least from here we can hold out a hand to those who get themselves in reach.

Do you hear the falls?

Monday, September 14, 2020

(Sea)HorsePower and Square Motorsailing


Full and Half-By with Todd Allen

Gentlefolk do not sail to windward.

-- I'd swear it was Sir Francis Chichester

(Sea)HorsePower and Square Motorsailing

Many years ago, Phil Bolger observed that, for the average sailor, most if not all sailing is done off the wind, with the motor being used for windward work. Furthermore, as many must sail on a schedule, he felt a faster transit to and from cruising grounds with leisurely, fun sailing once there was a plus for most.

As such, he began to design many of his vessels around that premise.

By average, one is sometimes tempted to think it means sailors with any sense at'all.

Note that by off the wind, one means the 180deg half-circle from a beam reach (90deg to the wind on one side), through straight downwind (wind on the stern), to the other beam reach (90deg to the wind on the other side). That's a lot of degrees of freedom... a lot of sailing!

In contrast, sailing to windward only allows half that from a beam reach to close-hauled (45deg to the wind on one side) and same again on the other. Plus, you're heeled over, often bashing into waves and spray, and the wind feels strong and cold.

So, despite motors being largely beyond my ken, I'll nevertheless share some musings...

Hull Design

Hulls that move through the water (as opposed to climbing on top of it) displace water ahead, downward and to the sides and are called displacement hulls. And all that pushed-aside water has to return to fill the hole left behind by the moving boat.

Some consequences for displacement hulls:

  • Speed is proportional to Length (S/L ratio)... the longer a boat's Water Line Length (WLL), the faster it can travel.

  • S/L = 1.34 x √WLL = maximum speed aka hull speed

  • It takes exponentially more power to approach maximum speed

  • Additional length provides diminishing returns in speed (longer is faster, but shorter is more speed per foot of WLL)

In other words and once again, small is beautiful.

Sailing boats heel (lean over) when sailing to windward. When they do, a wide, square transom dips its lower, lee corner under the water and drags. So we raise it to minimize the effect. Problem is, displaced water now has to travel more abruptly back to fill the hole we leave behind, creating turbulence and drag. Part of the price we square boat sailors pay.

But if we motor to windward, we do it upright (heeling is negligible). Accordingly, we can ease the aft curves by lowering the transom to kiss the water. You can see this in the picture above, and also see how little disturbance it leaves as it sails upright downwind.

So consider a transom with lower edge at the upright WL.

Another design element becomes practically negligible when not sailing to windward... Lateral Resistance. This is resistance to sideways motion, provided by dagger-, lee- and center-boards, keels, chine runners, etc.. 

Skip LR and all its many hassles.


The lion's share of rig complexity arises when sailing to windward. Sailing down and off the wind calls for little more than putting up and spreading a shaped sheet to catch the wind. Efficiency might be important, but for the average sailor, not likely. If we're going small, everything gets easier.

Here's what I'd look for in a rig:

  • Forward placement... Put the horse before the cart.
  • Easily mounted and stricken rig... When the wind is again' ya, take it down.
  • Easily handled... Why be fiddlin' while the sun burns?
  • Easily reefed... Just 'cuz we're loafing along doesn't mean the wind won't blow up!
  • Consider a free standing rig... No shrouds or stays to set up, take down or worry about in a jibe.

Quadrilateral sails (four-sided) spread a lot of sail on a short mast for easier setup and take-down.

Consider Ljungstrom Rig, which meets all of the above, and has infinite reefing, which can be dumbed down for smaller boats.

Mechanical Propulsion

I'm a fan of outboard motors over inboard for their ease of dis/mounting, lower installation complexities and non-perforation of the hull. Any fuel spills are relatively easily contained and reduce the risk of explosion. Many regulations for safe installation of inboards are avoided.

Options include electric, gas and propane (and natural gas)... each have their fans. Among electric motors, trolling motors are inexpensive and are designed for long run-times at lower speeds on a given charge.

Consider modest, outboard propulsion.

Remember that it takes exponentially more power to approach maximum speed, which in a displacement hull is in any case relatively low. This means you can run at some fraction of hull speed - say a half, two thirds or three quarters - with far less power input than for top speed.

Now, you hitch up a few horses (power is often measure in Horse Power or HP) and you can easily push a small load at low throttle, while sipping fuel (or Watts).

Consider backing down from top speed to radically extend your range.

Manual Propulsion

Me? I'd still carry a manual alternative to those finicky mechanisms. 

A sculling oar is simple and effective. An Atsushi Doi Power Fin is less simple, but powerful (could almost skip the motor). Oars are tried and true, though harder to handle. Even a paddle will get you somewhere.

Consider 'auxiliary' manual propulsion.


I'm going to present this f'r'instance cobbled together from correspondence with Todd Allen. He writes [my emphases]...

I've built my second Triloboats style boat, thought you may be interested.

This one is a micro version, 10 ft long, 47 inches wide (to fit in my utility Trailer!). Birdwatcher cabin, rockered hull with a taste of PDR shape at the bow. Cabin is 6 ft long, lots of storage under the decks. I added Oar ports on this one which I really enjoy using, both for rowing and for ventilation at night. 

I brought the lower edge of the transom down as low as I could to maximize displacement for supplies and to give as much buoyancy as possible to the rear section to support the weight of the motor. I got lucky and it's about right! 

Can maintain 2 mph easily under oars in calms. 

I mainly motor with my 2.5 hp Yamaha 4 stroke (24+ mpg), but have a small downwind sail I deploy as often as possible, using the motor as my rudder (turned off of course).

[I checked back with him about that great mpg...]

24 miles per gallon is not a typo! I love this little Yamaha 2.5 four stroke, one of the best things I have ever bought. I run it at just above idle most of the time, and this gets me to my cruising speed of 3.5 knots quietly. At just over half throttle I can get up to 4.4 knots, but louder and bigger waves. Full throttle digs a bigger hole, no real speed increase. 

One thing I'll note is my offcenter spritsail rig. Even though I set my boats up primarily for motoring, I find I sail as much or more than my traditional sailboat cruising friends because my sail is so easily set. 

I usually keep it up and brailed, so if a favorable breeze comes up, I drop the brail and I'm sailing, takes 15 seconds. Same for brailing it when wind dies. The slot top cabin of course makes this possible.
Makes me chuckle that mine is often the first sail deployed. Also chuckled on the last trip when a sailing friend complained that it took him so long to catch me going downwind in a light breeze in his 17ft Siren!

And there ya have it.

Saturday, August 15, 2020

Running Downwind: A Jibe in Time

Too much, too long, too late?

But at my back I always hear
Times winged chariot hurrying near:
And yonder all before us lye
Desarts of vast Eternity.

-- This and italicized quotes below from To His Coy Mistress by Andrew Marvell

Quality of life is preferable to mere quantity for the vast majority of us.

-- From Being Mortal by Atul Gawande

Running Downwind: A Jibe in Time

Was a time I was pretty much satisfied with putting one foot in front of the other.

You know... plod along the path of life in pursuit of the dream. Uphill all the way, with the peak somewhere well ahead. Vistas opening wide in all directions. And what hurry? There is world enough and time.

Somewhere in there, the 'peak' comes and goes. 

Now, I'm not one who believes in an apex of life. Rather, that the entire journey comprises our One Precious Life, and that be yum. But I do acknowledge that time's winged chariot is careening down a cul de sac. Windows of opportunity are edging toward closed. Somewhere not far ahead lie those Desarts of vast Eternity.

At a mere three score years, I yet see time's imprint more than feel it. But the next will likely see those strengths that have carried me thus far blunted and diminished.

Too many of our friends find themselves late in life aboard a vessel now too big to handle and/or maintan. Going or gone derelict, ship and master. The former content; the latter sad or bitter. Their life ended -as they see it - too much before the End.

Their main problem? They stuck with what they knew until they no longer had the wherewithal to transition to something within their diminishing reach.

So it's coming, and coming soon. What to do?


Okay. What kind of platform for living do we need? Need as opposed to want.

It comes down to two things:  A comfy, dry, warm home, and mobility.

Each of our sailing homes has provided both of these in one salty package. But the day will come when moving the home will likely exceed prudence, if not capability.

Our current best thought is to sail WAYWARD as long as seems wise, then haul her ashore as a fixed base. She's easy to board, heat and maintain (especially if sailing trim is no longer required). What's more, she's our bird-in-the-hand.

For extended mobility, a small camper-cruiser which can be rowed, sailed and hauled with relative ease. The smaller the vessel, the higher the ratio of muscle to boat. 

We can enjoy it as an expedition vessel into relatively dangerous waters while our abilities remain. Later on, the judicious selection of weather windows and a gentle pace. 

And when that won't do, adieu.


I don't often look in mirrors, and even more seldom do I look at my head from above.  So my self-image is of a head of thinning but definitely present hair. An illusion undisturbed by my loving partner.

A odd-angle encounter with our little, post-card size mirror on our boat, however, gave me a startling glimpse of the the rut time's chariot has left across my upper pate!  

Smiley Face - Looking Up - Men's Shirts - Whee! TV

So I leave you with this cautionary yarn...

A Cure for Baldness

An uncle of mine never allowed his hair to grow because he said that to keep it shaved prevented it from falling out... the sad moral came towards the end of his life, when he decided to give his locks their one fling, and nothing was left but baldness.

-- From Baghdad Sketches by Freya Stark

Saturday, August 1, 2020

Off-Center Masts for Off-Center Sailors

Don't get more off-center than this Bolger BRICK, TETARD
Note that crew weight has more than compensated
for heeling moment.

One does not walk into the forest and accuse the trees of being off-center,

Nor visit the shore and call the waves imperfect.
-- from the Tao te Ching

Think off-center.
-- George Carlin

Off-Center Masts for Off-Center Sailors

When we were building ZOON (ex Bolger LONG MICRO), we stood the aft mast in place, off-center, to see how it stood. A visitor to the project took three wordless passes around, humming and clucking at such unusual features as the square sections and bow transom. Finally, he draws himself up with hands on hips and exclaims, "NO. That off-center mizzen is just too much."

But that off- center sail was perfect. Squared off across the stern, we could run down the off-wind quadrant in a gale of wind with balanced power and a clear view ahead.

Since then, every boat has had at least one mast off-center for one reason or another. Masts at the aft transom are offset to clear the rudder and sculling oar. Those at the companionway are offset to allow center-line openings which, in a knock-down, remain furthest from the water and least likely to flood.

We've never been able to observe a sailing difference between tacks in our larger, relatively heavy cruiser size vessels. We will wing out the offset sail to its near side when running... from there, they overlap the foresail less and behave much better. Otherwise, it appears a draw.

But this one time...

I wrote this account in a previous post:
A friend of ours had built a Bolger BRICK (shaped about as it sounds). He brought it out to Tenakee for a Mess-About. All day, he and his daughter sailed circles around the rest of us (including respected designs of similar size by Devlin, Hess and a TORO!).
Circles, in fact, barely describes the figure 8s and jaunts across the inlet and back while our fleet trudged along in comparison.

I was wowed by this and have mused lo these many years upon it. Now I venture a theory...

The BRICK has its mast stepped along one hull wall, and very near the bow. The crew is live ballast, but in practice needn't move much around (according to its skipper). When I first saw the arrangement, I felt sure it would capsize mast-side at the first gust. But no.

Here's my thinking, taking the BRICK pictured above as example:

On the port tack (wind blowing from port across the hull to the lee-side sail) it acts as a proa. Windward hull lift is opposed by crew weight.

On the starboard tack (wind blowing into the wind-side sail, then across the hull) it acts like a normal hull (center mast). Leeward hull depression is opposed by outboard displacement.

Setting the mast at a point of maximum beam, in effect, doubles the beam! That dinky li'l x4ft punt has the equivalent lever arm at the mast as our x8ft WAYWARD. Whether sailing as a 'double wide' monohull or proa, the righting arm is twice what one can expect with a centered mast.

With such a doubling, one can fly twice the sail area or sail a normal amount twice as aggressively (which appears to be the case).

Somethin' to ponder on!

Picture this mast position as center-line!

Saturday, July 18, 2020


One of many approaches to Hobo ReelsIs that a KIRKLAND Whiskey Bottle cork capping the bottom???

50 Best HOBO HANDLINE images | Fishing kit, Bushcraft, Hobo
Rigged with hook, line and keeper

Alive without breath, as cold as death;
Never thirsty, always drinking;
Clad in mail, never clinking.

-- One of Gollum's riddles from The Hobbit by J.R.R. Tolkein

I'm a-goin' fishin',
Yes I'm goin' fishin',
Baby goin' fishin' too!

-- From Fishin' Blues by Taj Mahal


I've got to say right off that I'm not a fool fer fishin'. In fact, if fish weren't an important part of our diet and livelihood, I'd never set a hook. Anke, on the other hand, you might say is 'avid'.

For me, I'm looking to maximize the efficiency and minimize the sport. To do as little harm as possible, both to those too small to keep and those whose life is taken for ours. To cultivate a spirit of humble gratitude for a fish's life. To console myself with the knowledge that they are fellow predators dancing in the web of life.

For many years, Anke and I have subsisted on smaller fish- rock cod, pink salmon, dolly varden (between a trout and salmon). Lacking refrigeration and unable to carry the weight of jarred fish, these are all we can eat while fresh. Now, however, we have the displacement and tools for jarring, and have our sights set on larger salmon, halibut and dogfish (a small shark).

But these still swim mostly in our future.

Our fishing rods and reels are accordingly very light. Usually the cheap-0 kid's reels. They live on deck, ready to hand, and last a few years. But they're seldom made for salt water and get cranky. And they tend to hang up on this and that at inopportune moments.

Recently, I stumbled across hobo reelsDIY, compact and effective.

Plastic container types offer near instant gratification and are very practical, since they take little or no modification and securely hold a lot of gear for any given size. Check out hobo reels made from PVC.

Wooden hobo reels - whether carved or turned on a lathe - are just plain beautiful. But first, a digression...
At a Renaissance Faire I was once enthralled by a fellow turning chair legs on a pole lathe. He used a living sapling bent over as a spring, sprung by depressing a foot plank. A line connecting the two turned around a pulley on the lathe, and as he worked the plank, spun the leg stock for shaping. 
Unfortunately, it was otherwise a more or less standard metal lathe and, they being generally large and heavy, I hung on to the pole idea but roundfiled the lathe.
Back to hobo reels... one of the vids shows a feller turning one on a home-made pole lathe! OOH... now we're talkin'. It was clear to see that I could dumb his full-feature lathe down to a mini lathe sized for the hobo reel. An hour of cobbling from materials on hand and this is the result:

Ever the Muse brings chaos in her wake!
A bungee has replaced the spring pole.

Stock is skewered between a fixed point (left) and an adjustable point (right).
Two turns around the stock and it rotates around the points.

Never having turned anything, I grabbed a rather funky piece of firewood to try it out. To my surprise, the result would have been a keeper if I'd used better material! On to HR2.0...

Go small, go simple, go fishin'!

My Spice Jar HR left
and Lathe-Turned HR right


A few preliminary tips and tricks...

  • I've found that a single hook (vs. a treble) at the end of a line is easy to stow. Lure and / or bobber can be loop tied (pass a bight of line through a hole and around the item to form a cow hitch) as desired. Hook can be set into holes drilled around the spool base, or stowed in storage cavities with its line pinned by the cap.
  • Braided line (vs. monofilament) seems to work well, is much easier to handle and has enough friction for loop ties.
  • Instead of carrying one or more bobbers, an eye-screw can attach any found bit of flotsam with enough buoyancy.
  • For a bobber, consider a stick which can be thrown much farther than a typical bobber, hook and lure can be cast from a (rodless) hand reel.
  • If using a container, consider one with a pronounced flare (like one end of a spool) toward the casting end. This helps lift clear of the wound line while casting, reducing friction.
  • throat gorge (spine of wood, bone or metal sharpened at both ends and attached from the middle) is far easier to improvise than a hook. A fish swallows the baited stick which then toggles sideways to set. Size for target fish.

Our go-to fishing sources:

Indian Fishing Methods by Hillary Stewart
Living Off the Sea by Charlie White

A Coupla good, how-to vids:

And check out this guy's Rodless Reel!

Saturday, July 11, 2020

Bilgin' the Barge? Reflecting on the Pond

Princess Tuvstarr gazing down into the dark waters of the forest tarn
By John Bauer

Swim out of your little pond.
-- Rumi

Bilgin' the Barge?  Reflecting on the Pond

After the first day's sail aboard our first boat - a shoal, flattish bottomed life-boat conversion - we happily went about preparing a special meal for our first night at anchor.

To our consternation, some of our stores, stowed low and outboard, were mysteriously soaked! We checked the bilge under the floorboards and were relieved to see our customary few inches of water between lead ballast bricks (as low as we could pump it)... so we weren't sinking. Some fluke?

No further problems until the next time we went sailing. With the same, soggy result.

Turns out that, as we heeled, that little bit of water all ran to and piled up the low corner, climbing above the far end of our lowest shelves. Some water-tight storage boxes did the trick, but it left a bad taste.


So this is a general problem for flat bottomed boats, especially those with no rocker amidships. Not only does all that flat skim of water add up when concentrated, but when upright there is no sump (a low point which concentrates water for efficient pumping).

But do we really need or want a (wet) bilge at all?

The purpose of the bilge is to collect and contain water that makes it inboard from outboard (seeping planks, say, or leaky through-hull fittings). Or oil spills from the engine.

But there are considerable downsides:

Basically, a sailor with a wet bilge is living above a pond of... well... bilgewater. A pond is always moisturizing its environs and contributes to that dank, musty smell that many think of as boaty. Mildew and 'dry' rot fungi love the humidity. Wooden boat frames tend to rot near the standing waterline of the bilge. Most bugs die of dehydration, but not if there's a pond handy.

Bilges themselves smell better, nowadays, than in the days when raw sewage was among the fluids, but a 'sweet smelling' bilge remains rare enough to be noteworthy.

In flat-bottomed boats, a bilge must be created by raising the sole (floor you walk on) by at least several inches. Another way of putting it is that you must lower any given headroom the same amount.

Traditional construction approaches are sufficient to achieve a dry bilge. As Larry Pardey put it, would you rather pump or sweep your bilge? It requires careful building and installations, with consistent, proactive maintenance. But doable.

With modern gap-filling adhesives and milled materials, we can achieve that high bar with much greater ease. With no more skill than is required to pull the trigger of a caulk gun and spread with a paddle, we too can achieve a truly watertight hull. And preserve precious headroom!


In our boats, we go without a bilge. Generally, the inside of the hull is either the surface we walk upon, or against which we stow gear and goods.

This means, of course, that if salt-water gets in, you know it right away, and it's something to be dealt with pronto! As I've written, girder furnishings help contain any leak and localize any soaking.

In all these years, we've only had salt water intrusion twice. A new mooring ring sliced through two sets of line and chafe gear in a squall, and ZOON was blown onto a rock which ground a two foot hole through her side and bottom.

A wet bilge wouldn't have helped in this case.

SLACKTIDE drug two anchors while lying unattended in a squall and spent a happy few hours fracturing a couple spots in her bottom planking, which then seeped.

A wet bilge would have made life a bit easier, but then, we may never have fixed it by patching the inboard face? We're lazy that way.


Once again, each of us finds the path that suits us. Some may prefer to pump, some to sweep. Some might hedge their bets with a dry bilge on standby. Others remember the adage, a leaky boat never sinks (yer always pumpin' her!).

Keeps it interesting!

P.S.... One nifty, fail-safer solution is to build a 'step' sharpie or barge - essentially a wide, hollow, keel that can serve as a bilge in an otherwise flat bottomed hull. It only need be deep enough to do the job.

The drawing below gives the general idea... I couldn't find a pic of one applied to a flat bottomed vessel.

Modified Bolger Sharpie

Sunday, June 28, 2020

SIP RIP: Deciding Against a Ply / Foam / Ply Hull

Adding inboard layer of 1/4in ply
Next space to my right has fitted foam ready and waiting
Two areas to my right, the inboard face of the hull is exposed

This guy oughtta be wearing his ear protectors!

I think I'd better think it out again!
-- Fagin, from Oliver! lyrics by Lionel Bart

SIP RIP: Deciding Against a Ply/Foam/Ply Hull

A friend of ours built a shop with reclaimed Structural Insulated Panels (SIPs). It flew together, was obviously superbly insulated and was strong and stiff.

But commercial SIPs aren't typically geared for marine environments (though I wish they were). Custom orders are possible but too spendy for us. With tape n' glue construction, these would be the bomb. Sigh.

DIY ply/foam/ply adaptations seemed within our reach, and they were. We've now built two boats with two approaches, and both worked out (WAYWARD's example). But, looking back, we've (pretty much) decided not to do it again.

Insulation (R-value) is awesome and totally stopped condensation. Positive buoyancy is a benefit we hope never to call upon. But...

Here's a list of cons:
  • Framing is necessary, finicky and expensive.
  • Through-hulls need blocking (in advance or retro-fitted).
  • Installing foam and inner ply is time consuming and adds cost.
  • Voids (which can rot or mildew) are difficult to reliably avoid.
  • They can't be disassembled for inspection.
  • Foam takes away from interior volume.
  • Foam adds fire hazard with toxic smoke.
  • Foam is a pile of plastic waste that can never be "disposed of properly".
Framing deserves special note, and is what truly tips our scale.

Its purpose is to take fasteners for furnishings (vs. epoxy welding or tape n' glue which we prefer to avoid), tie the inner skin mechanically to the outer, join panels and seal edges (as around window cut-outs). It must be well-planned, precisely installed and devil take those who change their minds. Corners are particularly aggravating, and may need doubling up.

So what's our alternative?

We now lean toward two layers of ply, laminated (we like an LPC such as Gorilla Glue for this).

Condensation is much reduced by 1in of ply, and 1 1/4in (using one layer of 3/4in for accepting fasteners) takes it down to near none. While insulation is relatively low compared to foam, it's still adequate. Strength is high. Buoyancy is still positive, though reduced. It weighs a bit more. Cost is oddly about even (pound for pound, thinner ply is generally more expensive).

Best of all, interior framing is eliminated... you can fasten anywhere into the wall or drill right through it without blocking.

TriloBoats are intended to be quick and simple as possible. We've found that ply/foam/ply in the hull sides run against that grain. While the results are good (at least in the shorter term), we feel that the net benefit doesn't pay for the effort.

Should we build again (please O Great Spirit, NO!), we'll continue to use a SIP approach for the main deck but go to a solid wall hull.

So R.I.P., S.I.P.s.