Glide Rig: A Hybrid Rig for Rowing Sailboats

 

MUSTELID gliding along
Full Foresail - Roll Reefed Main - Driver

All I wanted was a tall ship

And a star to sail her by

  Through the night.

  Through the night!

-- Motherlode?

Glide Rig: A Hybrid Rig for Row/Sailboats

Why name a rig? Any technical description is a mouthful, and few people appreciate mansplaining. A good name is evocative, calling to mind traditional associations. Or suggestive, offering a clear clue to the nature of its subject.

Gaff Rig, for example, suggests the spar itself and the sail's quadrilateral shape follows. It evokes robust working sail standing against the gale. The more initiated might recall its ability to scandalize—dumping half its area in a sudden gust. They might recall peak and main halyards, running backstays, and the tack-to-peak creases that indicate a correct set.

So, here is a rig in search of a name...

But first, the mandatory get-in-the-door question from The Commitments: “'Oo are your influences??”

Phil Bolger (of course) observed that most of us aren't out to win a race or even do much sailing to windward if we have any choice in the matter. Outboards and engines mostly handle the windward hemi-circle, so why expend design effort, gear and $$$ on maximal windward ability? He accordingly started to offer simpler, cheaper rigs.

That got us thinking. For a rowing, mostly downwind sailboat, we want a long, slim hull. These  are easily driven but offer relatively low form stability. Ultra-shoal draft limits ballast stability. A snug, low-center-of-effort sail plan that is easily handled and reefed pairs perfectly.

On a row/sail craft, we primarily want the sailing rig to pull us down- or across the wind. Positioned well forward as a foresail—clear of a forward rowing cockpit—it should provide powerful lee helm and steady, balanced traction. For sailing upwind, however, the balance picture changes. We want the total CE moved aft to for weather-helm and good tacking.

Quadrilateral and spinnaker-like sails work, but don't transition easily between the two modes.

Enter Frederick Ljungström, inventor of Ljungström Rig a boomless, double Leg o' Mutton (LOM) triangular sail attached along a shared luff to a  rotating mast. Off-wind, it sets and handles much like roller-furling twin staysails, and like them, provides considerable upward lift.

Sailing into the wind, the sails are doubled, overlapping on the lee side and sheeted as one. This constitutes a half-reef, and a large aftward jump of its CE.

To reef, the mast rotates (we prefer righty-tighty, lefty-loosey), furling the sail snugly around the standing spar. No halyards, tack or clew downhauls, bunts, or nettles. Just roll it up and carry on! As a bonus, simple flat-cut LOMs furl tightly with minimal windage, forming conic sections similar to a Crab-Claw rig.

Since a slim hull cannot spread wide sheeting angles, we re-introduced booms along a loose foot. The result is a doubled variation of the Holopuni Quick-Rig (a great name!) which is similar to a setup offered on the SeaPearl 21.

Finally, three-masted junk schooners (e.g., CHINA CLOUD) inspired us with their fine control of their relatively low total CE, bow and stern maneuvers, and reduced area on each mast. Even on a smaller vessel (within reason), the advantages of multiple masts are striking.

Why Balance Matters When Rowing: Multiple sails give fine control over the balance of the helm. Especially when "motorsailing" (row AND sail), good balance leaves our hands free for the oars and reduces steering by stroke with ensuing fatigue. Even over a short haul, that makes a big difference! A driver - often set while rowing when the others are stowed - helps hold the bow up toward the wind. Where the bow want's to 'blow off' this is an asset.

A Problem on the Side—and a Solution

There is a catch with standard booms. They are fixed at the mast and sheeted toward their outboard end. As the sail is reefed, the clew moves inboard of the sheets, pulling laterally on the mid-boom, bending it toward the CE. Heavy spars and compromise arrangements are the usual fix.

Our solution? The Gliding Grommet.

We use a rope grommet that glides along a lightweight boom, with both the clew and sheets attached directly to it. A light clew/sheet outhaul is led through a turning block at boom's end, spreading the sail as desired.

When reefing, ease the outhaul, roller furl the sail as needed and make the outhaul fast. The grommet, clew and sheets are move inboard along the spar. The active, loaded portion of the boom automatically shortens, increasing relative strength. It absorbs the load purely in compression, avoiding mid-span bending stress. Cheap, DIY, and it works like a charm.

Glide Rig Specification

Mulling all this together, pulling out the main points and generalizing, we arrive at...

The "glide" emphasis is on downwind sailing and a strong balance shift for upwind sailing, supported by the working rig (I.e., without sail changes):

• Foresail in 'cat' position (well forward) and,
• Sets large area for off-wind sailing
• Reduces area and moves CE aft for upwind sailing
  
  
• Main near amidships and/or,
• Backs up the foresail for downwind sailing
• Becomes the driving upwind sail
  
  
• Driver well aft
• A smaller sail for balance and riding

"Glide" can be used adjectivally in the usual manner... where we would say "That's a junk schooner, ketch or yawl", we can say "That's a glide schooner, ketch or yawl" or combine them, "That's a glide junk schooner, ketch or yawl." 

Generally speaking, we wouldn't apply the glide adjective to schooners, ketches and yawls that don't pass drive from the foresail to main when switching from down to upwind sailing, and vice versa. Ditto cutters, sloops and catboats.

But any schooner, ketch or yawl is arguably a glide rig. It's a threshold, as is often the case. Boundaries are fuzzy and often the subject of over-heated tavern debate. Personally, I find it a simple matter of personal perspective... we each get one and to each their own.

With this in mind:

• Two- or three-masted schooner, ketch, and yawl variants may qualify.

• Main and driver with other planforms and rigging may qualify.

• Rig particulars—such as specific sail planforms, unstayed masts, roller furling, the Gliding Grommet solution, and such—are handy but optional.

NOTE: We call the stern sail a driver... it seemed the better option among mizzen (confusing), jigger (???), dandy (too high-brow?) and spanker (let's not go there).

MUSTELID's Glide Rig

I would now call MUSTELID's a three-masted glide LOM ketch rig. Fore and main sails are of equal height. LUTRA's main will be slightly taller (also quadrilateral with a sprit in the mix), so I'd call her a three masted glide hybrid schooner rig.

We tested Glide Rig extensively in MUSTELID over a wide range of conditions, as documented in the video series, MUSTELID Venture.

MUSTELID's foresail is a Ljungström sail (double LOM) rigged and positioned as described above.

Her midships main is a single LOM boomed as described and set aft of the forward cockpit. In this position, it becomes the heart of any windward sailing we might do, with the foresail reefed (moving the combined CE aft) and doubled over to sheet as an LOM. We offset this one to clear the BIRDWATCHER cabin's mid-line companionway.

We set a small LOM driver dead aft for offwind sailing, to 'crank in' weather helm, hold the bow up when drifting and serve as a riding sail. It is a big help when rowing in headwinds, especially when we must row at an angle to the wind. This sail was offset opposite the Main to clear the rudder and tiller. In this position, it can be squared across the transom for a mid-line, downwind push.

It is sprit-boomed in pretty much the standard manner. The boom is longer than usual, extending forward of the mast. A U-sheet leading forward attaches one leg to the inboard end of the boom and one to the outboard. This gives us leverage to trim and make fast. The sail is fixed to the mast (no halyard)... to stow, we release the snotter and raise the outboard end of the boom alongside the mast. A light line fixed to the masthead is used to wrap and secure the boom and vertical, hand-rolled bunt of the sail.

Roll yer own and glide on, Friends!

Rigged for Success: LOM/Ljungstrom + Quick-Rig Booms

 

MUSTELID's LOM Main and Ljungstrom Foresail

Live life as if everything is rigged in your favor.

-- Rumi

Rigged for Success: 
    LOM/Ljungstrom + Quick-Rig Booms

I'd like to share a suite of ideas toward a family of lesser known rigs for smaller vessels that I think show a great deal of promise. Part historical, part convergent evolution, part innovation, the result is a simple but versatile, robust rig that can be DIYed at low cost.

Leg o' Mutton (LOM) Sails

This tasty moniker simply means a triangular sail. They're commonly used for headsails (jibs, staysails, etc.), mains (often called Bermudan sails) and drivers (small sails set far aft).

Ljungstrom Rig (2 x LOM)

Ljungstrom Rig uses a pair of LOMs, joined along their luffs and set on a free-standing, rotating mast. No booms were used to avoid troublesome impacts with crew.

This configuration works similar to twin head sails off the wind. From a beam reach on up, the sails are doubled over to one side and sheeted as one.

Pros:

• Boomstrike is eliminated (the rig's original focus).
• Light, inexpensive spares and gear.
• Quick set/reef, roller un/furling via the mast.
• Sailing off-wind, one side can be jibed for 'instant' 50% reef.
• Sail area aloft catches higher, upper wind-flows.
• Low Center of Effort (CE).
• Twin sails tend to center down the wind.
• Potential for hands-free operation.
• Sail steering is straightforward (haul to the side you wish to sail).
• UV resistant fabric along luff and foot eliminate sail covers.
• At least in smaller vessels, the furled rig is easy to set and strike, and compact for storage.
  
  

Cons:

• Lack of a boom makes spreading sail difficult (especially on narrow hulls).
• No clew outhaul or vang options.
• In contrast to twin stays'ls (unless the mast is canted) it generates no bow lift.
  
  

Adding a Boom

The addition of a boom set under a loose-footed LOM allows spreading, a clew out-haul and vang, addressing the main cons.

Interestingly, this approach was taken by both the Sea Pearl 21 (adventurously sailed by Stephen and Ginny Ladd, among others), and is marketed as Holopuni Quick-Rig (by Holopuni Canoes). Convergent evolution?

Both of these designs lead their clew outhauls via track along the top of the boom and sheets to the end of the boom. When the sail is reefed, the upward pull of the clew at mid-boom is resisted by the end positioned on the mast and the downward pull of the sheets at boom's end. 

As a sail's belly is blown full, pulling the clew strongly toward the tack, the boom resists in compression. If it is deflected from straight by the perpendicular pull of the clew between mast and sheet lands, that strength plummets. Usual solution? A heavy boom or one made with expensive, exotic materials.

Hmm.

What if we oppose sheet and clew tensions by having them meet at the same point? They cancel out, unloading the mid-boom! The clew outhaul - led to boom's end, then turned back toward the mast to the clew completes the picture. A rope grommet - travelling along the boom - is the perfect attachment point... simple, cheap and DIY.

Principle parts of the rigging...
This platform and 'collar' are primitive but functional

How We Go About It

Rotating Mast and Gear

In our small-ish boats, we went with a thumb-sized dowel protruding from the rounded bottom of the mast. This is inserted into a hole in its step - a fixed plate of thick HMD (cutting board plastic). This secures the foot but it allows it to rotate with very little friction. The upper partners are simply a loose-fit, fixed square around the mast. The distance between step and partners should be between 10% (minimum) and 15+% (healthy) of the mast's overall length for adequate cantilever.

A gate can swivel open to free one face for raising/lowering or close and lock to contain it. 'Box' sides at the step hold the foot in place for lowering. A pin led through one side and into a corresponding hole in the lower mast prevents rotation against high winds or rock and roll.

Each boom requires an arrangement that fixes their height above the partners, yet allows the mast to rotate independently. 

Our solution is a platform affixed to the mast with a collar from boom's mast end, around the mast, set above the platform... the collar is not so loose as to slip below the platform, but not so tight as to grip the mast.

Booms

Booms can be quite light as compression span decreases as the sail is reefed, and diameter per unit of span increases - functionally speaking, reefing makes them stronger. Further, they are subject to no significant side forces along that span. Sea trials help settle in on a light boom with comfortable margins of safety.

Each boom has a rope grommet loosely fit around it (sized so it doesn't bind when pulled at a flat angle). 

We fix a pinch cleat for the clew outhaul at the boom's mast end, pinch horn down (10deg) toward the distal end. This allows the line to ride over the non-pinch horn (up and toward the mast), under control hands-free as it pays out while furling.

A ring seized to the distal end of the boom turns the outhaul back toward the grommet.

The outhaul leads from its cleat, through the grommet (helps control a slack outhaul) to the turning ring, and back to the grommet. We fix it to the grommet's upper side, allowing a tail which is tied to the clew. We prefer little play between clew and grommet.

The sheet is fixed to the grommet's lower side and led to deck level. A turning device (multiple or travelling for an improved lead?) leads it toward a clear, handy to the crew. We prefer enough friction on the cleat to hold in steady wind but ease in heavy gusts... no lock hitch.

Sails

We used light nylon fabric to build flat-cut sails. These are responsive, and furl neatly around the slightly tapered masts. They are stretchy enough to take on some belly (camber) when full of wind.

Downside is that camber can't be flattened easily in high winds. But reefing is so easy, we can reduce power that way.

For 2xLOMs we screwed the webbed luffs to the mast, but are now considering a pocket for easier installation and removal. Others have found that a simple lanyard from tack to mast is sufficient for furling.

Handling the Ljungstrom

We set the Ljungstrom sail well forward, where it can pull us bow down the wind. 

We don't typically vang our sails to flatten them. Instead, we vary the sheet leads and/or reef a little more than we might. This avoids extra gear, handling and the heavier booms required. Personal call, however. 

Furled Set Up

When furled, the sail is snugly wrapped around the mast. The boom(s), if any, are vertical. Sheets are left slack and hanging. One clew outhaul is marline-hitched once or twice along the mast, securing all the bits, then made fast at its pinch cleat (low).


Setting Sail

Unhitch the outhaul, then refasten to its cleat. Uncoil sheets and lead aft to their cleats. Both outhaul and sheets will go slack as the sail is unrolled. Unpin mast if locked.

Depending on wind, you might wish to round up. For downwind departures, you may have to work in stages, trimming sheets as you go.

Unroll the sail by rotating the mast (we prefer 'righty-tighty; lefty-loosey' as standard... we do this by hand, but various rope windings are possible).

Once unfurled as far as desired, haul the outhaul(s) for the curve you wish, then make fast. Trim sheets and fall off to heading. Backing sail is easy and effective. If you wish to open the sails, do so.

On the Wind

Here the sails are overlapped and are sheeted as one (outer one generally the focus of our attention). They handle pretty much as any boomed LOM.

Off the Wind

Sailing off the wind, the sail is typically balanced like a delta kite. All things being equal, it want s to hold the bow centered downwind. More belly is often a good trade-off against more area.

To steer using sail, haul the sheet on the side toward which you wish to turn (easy, now!). This shortens its force vector and directs it to that side. The opposite sail, now relatively stronger and with a longer lever-arm, works to rotate the hull that-away. Like the reins of a horse!

In a heavy gust, you have a 50% reef at hand. You can jibe one sail (lapping one over the other) or let it fly (this can be harder to retrieve... get a wide angle). But if this comes up, consider roller reefing ASAP. Consider that, in high winds, you don't have to set them wing and wing... they sail well as one.

Odd Situations

If a sudden squall has invited letting both sails fly (they're trailing down the wind from the bow), calmly roller reef until you can bring them in and under control.

If such a situation has reversed their usual sides, don't panic... just hand the sheets around the mast, or refasten them for a fair lead and carry on. The sails won't care.

The whole mast, sails and all, can be furled, hitched up and let over as a sea-anchor.

All in All

We found these LOM/Ljungstrom + Quick-Rig Booms to be simple, cheap, versatile and powerful. Each piece is DIY-able from scavenged materials. Nothing about them couldn't be made in the field, at a pinch.

The lightness of the spars is a BIG advantage, especially as we age. The masts should be manageable for as long as we're likely to be able to row.

In researching the history of the rig, the few who have used it are soberly impressed by its virtues. It is not the fastest rig out there, but its no slouch, and pays its way with easy handling and quick reefing.

I'm hoping to see more of these on the water in the coming years!

Full Ljungstrom / Reefed LOM
Sprit-Boomed LOM Aft

References

Sea Pearl 21 Review by Josh Colvin

About Holopuni Canoes by Nick Beck

Rigging MUSTELID and MUSTELID Voyage by Anke and Dave

Natural Navigators

 

Seems kinda simpler on the water!

From Crowd Motion Patterns, Dupont etc al. (2017)

Watching a child makes it obvious that the development of [their] mind comes through [their] movements.

- Maria Montessori

Natural Navigators

Line of sight navigation - lines of position, ranges, transits, relative bearings - is the simplest kind of look-see reckoning. No numbers, calculations or algebra! Given fixed visible points and rough angles, we can tell where we are on the water. With a second glance, we can tell if we're advancing, clearing or if another vessel will pass ahead or behind.

Simple.

Yet many struggle with the concepts involved. Many feel that such skills are beyond them. That there is something mystical or arcane in their ways.

I won't go into the details as they're well documented elsewhere. Rather, I'd like to point out that we use these skills daily without giving them the least conscious thought. We're ALL navigators from our early infancy!

Come with me for a walk in the park?

We're walking along a path bordered by green grass. We encounter others strolling along. Occasionally, we overtake a group going the same direction, and pass through with nods and 'hellos'. We see a vendor's stand to one side and pull off for ice-cream.

Lovely.

Of course, we've been navigating the whole time. We've not overstepped the path to tread the grass. We've tended to the right as have those coming towards us. We've threaded a 'fleet' of slower folks without bumping. We cleared the corner to the vendor's 'cove' and entered.

We do this every day. We walk toward our destinations. We walk through doors rather than crash into the walls on either side, coming and going. We assess and adjust our course and pace, relative to others in motion.

The only difference that makes navigation on the water feel uncanny is that we aren't generally providing the physical impetus of our own motion. Wind and water move us along as we sit and admire the view. But line of sight navigation remains the same. We adjust our course and speed according to what we observe, just as we do ashore.

It ain't magic!

 

Metronomics: Understanding Roll

Note the weight positions... higher = slower ; lower = faster

Now roll on, Buddy?
Why ya roll so slow?
I gotta roll slow
With my weight so low.

-- Adapting a Folk Song

Metronomics: Understanding Roll

Being an Old Fart, I had the privilege of growing up with mechanical metronomes. Mechanisms - as opposed to algorhythms - that set and keep the beat.

Metronomes keep the beat, adjusting their tempo by sliding a weight higher or lower along a bar. 

Higher Weight = Longer / Slower

Lower Weight = Shorter / Faster.

Puts me in mind of the dreaded short and snappy roll that fatigues and throws crew around if not overboard. Longer, slower roll periods are desirable. Up to a point. Beyond that point, they can become self-reinforcing and enter 'death roll' dynamics. We're with Goldilocks... we're looking for a sweet spot that's juuuuuust right.

Being a sailor, I can't help but see roll dynamics in the metronome.

Bar = Mast
Weight = Rig's Center of Gravity (CG)
Axis = Hull's Center of Buoyancy (CB)
Counter-Weight = Ballast CG

Tempo = Roll Period

The connection is easy to spot. We can adjust roll period (by raising and lowering the Rig's CG while all other points remain constant.

A baseline is established by weight distribution along the mast, most likely at construction time. Hollow masts offer lots of options for messing with distribution via placing of  internal weights. Choice of hardware (e.g., masthead fittings, blocks, spreaders, etc.) for weight placement all count. Designers aim for one-size-fits-most.

Junk Rig is interesting... as the sail is raised, more weight goes aloft. Typically the yard is heaviest at the top, while battens average out(?) along the mast. The total effect is that more sail slows roll.

This suggests the possibility of elective roll period manipulation via weight that can be raised and lowered to adjust for conditions. The challenge would be a 'doohicky' which would observe these Thou Shalt Nots...

• Not be difficult to deploy
• Not interfere with the rig
• Not swing wildly
• Not be difficult to dowse
• Not be difficult to stow

While giving a seriously positive return cost/benefit ratio-wise.

Clearly, the need for roll control will all have a lot to do with the roll dynamics of the hull in question. Low form stability (/easily driven) hulls will benefit more; Form stable (/it's complicated) hulls will benefit less.

How do you roll?

Simple Sampan

 

Sampan Bow
Arrow points to the forward end of the straight chine
a.k.a aft end of the bow curve

Simple Sampan met a Boatman,
    With a seaward stare;
Says Simple Sampan to the Boatman,
    “Let me take you there.”

- Olde Mother Sloops

Simple Sampan

Sampan bows have several benefits over western, pointy bows.

They add positive buoyancy at the bow, reducing pitching and helping to ride up and over waves (rather than plow through them). More interior volume is added for forward storage. Forward deck space is widened for better footing and anchor handling. Wide flare at the bow helps toss waves to the side, rather than over the top. The wide forefoot is more stable on a steep beach. It's much easier to roll a cross-log under to protect the bottom on a rough beach.

We LIKE 'em!

With two sampan bows under our belts, I'd like to share some thoughts on dumbing the process down to manageable. This approach uses western design techniques, but leaves the bow to a traditional, 'follow-the-materials' attitude.

In designing your own approach, consider models from paper or cardstock. Fast and cheap compared to plywood!

NOTE: I've simplified since the first draft!

Simplifying approaches

1. Use constant flare
2. Begin with parallel sides, straight along sheer and chine
3. Use a simple, fair bow curve at the forward end (approaching a circle)
4. Build to forward end of the straight chine with bow extending past
5. Roll bottom upward to plank the bow

Okay, let's unpack that... I'm going to boldface some common boat terms you may have to look up to keep it short...

Decide the amount of flare. The simplest case is a constant amount of flare, which produces constant bevels along the chine. We find slope to be the easiest to work with, often 3in of lean-out per vertical foot. A changing amount of flare produces twist, which introduces rolling bevels and generally complicates things.

Parallel, Straight Sides - When laid flat, these are like wide planks. When bent over flared stations that converge toward bow or stern, they develop parallel curvature... 'sheer' along the sheer and 'rocker' along the chine. The more flare and the more the ends are brought inboard, the greater the curvature.

Phil Bolger (TEAL, among others) and Tom MacNaughton (SILVER GULL series) and others have designed handsome, capable vessels with this approach to side planking.

Fair Bow Curve - This curve provides the sampan shape. A curve closer to a circle provides a more blunt entry, while a curve closer to half a parabola makes an easier entry. This is laid out directly on the side planking.

Build from mid-section to fwd end of straight chine - This portion of construction is very easy. Constant bevels and simple, fair curves. Under these assumptions, side heights are all the same. The whole thing pretty much shapes itself! 

Meanwhile, the curved bow ends are sticking out there in space. Depending on your building philosophy, the bottom can be planked to this point with the proviso that you will need to continue bottom planking forward, rolling it up and over the curved, Sampan ends. 

Roll the bottom upward - To make the curve with plywood planking you will likely have to use kerfs.

If not using tape and glue construction, we find 'nailers' to be an easy method. Basically, these are planks along the curve to which the bottom can be mechanically fastened (nails or screws).

Ply Nailers installed and trimmed to bow curves...
Planks are a better choice, if available

Planking up the bow...
Note kerfs visible across upper bow

Nailers after bow is closed

As you can see, you have to get creative with clamping. There are a zillion ways to go. Most of them work, eventually. Try to find what works best for you!

NOTE: The black schmooey is DAP Polyurethane. Very strong bond, highly elastomeric, workable and about 1/4 the price of some of the name brands.

Complexifications

The previous assumptions are the simplest among flared side designs. But each builder and vessel is individual... you get to decide what pays off in your long-run. Your design and/or construction abilities will loom large at the beginning. A long-term benefit may well reward extending those abilities at the outset. Simplest is always fastest, but that's not the only question. Weigh it up!

Both chine and sheer curvature can be enhanced or diminished by curving one, the other or both (not necessarily parallel). Lofting will take up more of your time.

We cut our sides down from a single run of full width plywood, so strictly parallel sides are arbitrary. We chose to add a little extra sheer for vanity's sake (okay... it also gives a little more freeboard, forward, but that's pretty minimal). 

Note the riser above parallel over the forward end... that's a simple way to get extra freeboard, storage and foremast bury. In MUSTELID, we built it up from the sheer; in LUTRA, we're simply cutting above the (nearly) parallel cockpit line.

As mentioned twist complicates matters, but may pay in the long run. Generally, it helps increase sheer and rocker, and narrows the forefoot (for an easier entry). There's a bit of extra twist available for 'free' along the bow curve... consider making sure that it fairs in along sheer and chine with no hard spots in their longitudinal curves.

Bulkheads don't have to go anywhere in particular, but it's handy to have one at the point of maximum beam (not necessarily mid-ships) and one at the forward end of the straight, parallel chine, both definitive points. Intermediate bulkheads need to be adjusted for their position on the curvy sheer and chine. Many vessels can be designed and built around their bulkheads, with no temporary stations at all.

Simple's a great place to start, but you're not obliged to limit yourself!

*****

Box Barges are as simple and easy as a boat gets. I'd put parallel sided, flared vessels at the next rung of difficulty; still in easy reach. Giving up parallel takes another rung, but we're not dizzy, yet.

A Sampan Bow complements all three, and comes down right handsome in flared hulls!

Related Post: Roll Your Own

Plywood Construction for Less

 

Popeye Character by E.C. Segar

A vessel should be built as cheaply as possible. 
But no cheaper.

-- Adapted from Albert Einstein

Plywood Construction for Less

If we choose to build in plywood, before long you'll hear the statement: You'll be building with marine plywood and epoxy, of course. Both are fine materials and considered to be state-of-the-art.

But... here's where I find myself after three decades of boatbuilding for full-tie living aboard / cruising in the Pacific NorthWest (rainforest).

Marine Ply vs ACX

Marine plywood (MP) is AA (meaning both sides are nearly flawless), should be free of voids, have plies of equal thickness and relative more plies for any given thickness. It's a available in a number of species, each of which have a suite of virtues. The result is a stronger panel for its thickness when compared to plywoods of lower standard along any of these vectors.

The curious thing is that MP has mostly enabled boats to be built which are adequately strong, but lighter - using thinner marine plywood than if using lesser plywoods. Lighter means easier to drive toward a vessel's hull speed for a 'faster' boat. Except when using extreme methods the weight savings are slight for most cruisers.

In other words, the high price tag for marine ply buys 'speed' within a very narrow range (let's say from 0 to 4 - 8 knots). This is important for racers, but not nearly as much for the rest of us. 

ACX (one near flawless side, one OK side and eXterior glues) of decent species (fir, various pines, spruce and cedars) should last about as well as all but the most specialized MPs).

From ACX, we can build a strong, potentially long-lived vessel for far less cash outlay.

If we can personally pick through piles of ACX and have located a vendor with generally decent stacks, we can:

• Check for voids. Use a wire to assess edge gap depths... shallow knots are easy to fill, deep voids may be injected with glue.
  
  
• Check for an odd number of plies. Even numbers double interior veneers... in case of outer veneer failure, these are transverse and weak. Most 1/2in house sheathing plywood is 4 ply.
  
  
• Check for even ply thickness. Reject outer veneers which have been over-sanded.
  
  
• Check for general damage and irregularities. Reject as needed. If you know how much of a sheet you'll be using, damage can be allowed in offcut areas.

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NOTE: When going through stacks, consider being scrupulous about re-stacking. You'll not only be welcome back, but you'll get a lot more help from appreciative, unpissed-off staff.

Epoxy vs PolyUrethane

Epoxy Resin is amazing stuff. Water-proof and solvent resistant once cured. Small molecules penetrate well and make the most of micro-surface areas. Various additives alter its properties for a wide range of uses. Its application is well understood and documented... although winging it is not recommended, with a little research and discipline, even beginners can get good results.

But it's expensive, toxic (mainly skin contact while wet), generates a small mountain of waste, requires special, hazmat disposal. 

While plastic (bendy), epoxy is not elastomeric (stretchy). 

Here's the rub: while most modern construction adhesives exceed wood fiber strength by a large margin, that wood fiber strength is the limiting factor. Merely plastic adhesives can point- and edge-load wood fiber until it gives, loading the next fiber in line. Elastomeric adhesives spread the load over a (small) region, allowing wood fibers to act together for much elevated failure thresholds.

We do continue to use epoxy in small amounts, mostly for minor repair. But it's down to a trickle.

PolyUrethane (PU) and Liquid PolyUrethane (LPU) are moisture activated, waterproof and solvent resistant when cured. 

LPU expands as foam to fill gaps. This is handy so long as we recall that expanded foam is considerably weaker than the unexpanded, non-elastomeric glue film. LPUs have a quick turn-over time that can be freaky, but helps move the project along.

PU is gap filling but does not expand but is highly elastomeric. Not all are created equal, however, so check the specifications of your candidates! Before cure, it can be thinned with mineral spirits, turpentine and various oils. This makes it more compatible than epoxy with oil / pine tar finishes (we've found that it has considerable adhesion over oiled wood, especially when thinned a bit... fasteners are primary in these cases, however, on a schedule to take the full, expected load). PUs tend to have long working times (varies with brand, temperature and humidity)... this is a mixed blessing, depending on the task.

Encapsulation vs Breathable

Encapsulation means sealing the hull completely with a waterproof, usually composite barrier (fabric, resin, primer, paint). Great system. But waterproof isn't proof against hard knocks. Dings let water in, and it can't easily get out. A season of haul-out for thorough drying is advised, with solid springtime maintenance on its heels. For full-time liveaboards in a wet environment, it's a long-shot.

The old, reliable method is oil and pine tar. It wipes on in the minutes of dry between days of rain and can be done piecemeal. It's water resistant from the moment of application. It breathes and moves with the wood.

It's not only cheap, but can be made DIY.

Conclusions

Here's our current thinking for less expensive construction. We've tried most of this on one scale or another, and find ourselves returning and doubling down.

• Select ACX plywood - Fir if available. If laminating, A sides out.
  
  
• LPU Glue for lamination - LPU has good adhesion in close contact and foams up with less of adhesion to fill voids, but even this lesser bond is considerable. We don't use LPU for small area jobs, however, as it has frequently failed in these cases (non-elastomeric). Consider its use for some bulkhead framing (which can be wider area), backed up by fasteners.
  
  Brands include Gorilla Glue and less expensive AkFix.
  
  
• PU Glue for high-stress bonds - Chines, bulkhead / transom edges, deck-hull-joins can be made with chine-log construction and/or tape-and-glue methods (similar to epoxy, with PU thinned for tape saturation).
  
  Brands include 3M5200 (the gold standard, but expensive) and DAP PU Construction Adhesive (much cheaper and seems indistinguishable in practical performance on wood).
  
  NOTE: One advantage of PU is that it acts as a gasket, even with near-zero adhesion (contact using fasteners, say). Being elastomeric, it is compressible to create a water barrier. In these cases, any adhesion is gravy.
  
  NOTE: We haven't tried it, but think that PU in tape-and-glue should be a good match for copper bottoms with mechanical fasteners. Epoxy and tape doesn't seem like it would be as resistant to water penetration as it wouldn't likely form a happy gasket around fastenings for copper. Could be wrong on this, but it's an expensive experiment.
  
  
• TiteBond III for sheathing - Especially with a fabric matrix, this is relatively inexpensive and easy to apply while producing a durable, waterproof barrier that is easy to maintain and repair. Topcoat with primer and paint.
  
  NOTE: We're about to try concrete slurry with a fabric matrix for deck sheathing. Hoping for low cost, longevity and good footing while avoiding paint topcoat. Will keep you posted with results! Might even work for the hull above and below the waterline (though we won't be trying that).
  
  
• Oil / Pine Tar for sealing - Without a fabric matrix, these (in various Boat Soup proportions and recipes) are inexpensive, can be applied in a wide range of conditions and results in a breathable finish (moisture can come and, importantly, go!).
  
  We're trying a primer coat of tung oil (we've read that it's more resistant to mildew than linseed oil... so far so good) with  10-20% pine tar (can be purchase inexpensively at agricultural supply stores as treatment for animal wounds) and thinned by turpentine as conditions require (We're building in winter. Again.).
  
  The top coat can range from 50-100% pine tar. In the interior, we'll try furniture wax over the primer coat for the interior for a wipe-down finish.
  
  

Last Thoughts

One conjecture from George Beuhler that rolls around my head is the use of asphalt roofing tar for lamination. He noted that it's very adhesive once set (most volatiles evaporated). It would be far less messy between sheets of ply!

We've used it with success for various small jobs around the boat. Once set, it can be painted with latex paint without bleeding. White paint helps keep it cool and solid in (at least our PNW) sunny weather. On decks it can be topcoated with aluminamized trailer paint with a slight stipple for good footing.

A last possibility we toy with is using trunnels (wood 'nails') rather than metal. They're time / labor intensive, but superior in almost every other respect. Maybe in our next youth.

Lots of savings possible if building out-of-the-box!

Learning to Trust Myself

Kyūzō from Seven Samurai
by Akira Kurusawa

I wish someone would give me a whole box of those sharpening guides and gizmos... so I could have the pleasure of dumping them overboard!

-- Dynamite Payson (as remembered)

Learning to Trust Myself

I'm one of those guys who spends an inordinate amount of time trying to find the easy way forward. Sometimes, this effort pays handsomely. Other times, I waste my effort in attempting to fix what ain't broke.

At present, we're building a boat in at least semi-traditional style. That is to say, it's plywood, but fastened  and bedded -- rather than glued -- together. Mostly. The critical joinery must be carefully and correctly shaped without reliance on modern, gap-filling adhesives. This calls on skills which are rusty at best and at worst heretofore unacquired.

Two cases in point...

Rolling Bevels

Rolling bevels are a cut along an edge where the bevel is not constant, but rather rolls along a gradient between known angles. This kind of loosey-goosey process is terrifying to my ordered mind, and I have successfully eliminated them from TriloBoat construction.

We once were drafted into a professional effort to roll a bevel along a long, thick, expensive plank. One pro ran the plank through a bandsaw while another called out angles marked at intervals along the plank. The angle of cut was changed by angling the plate with a protractor/handle arrangement. Our job was to shift the handle "slowly" and "smoothly", transitioning between the angles being called out.

I mean, c'mon! I can call out numbers as they slide by me with one eye covered. But to make the correct transition? THAT is a pro job foisted upon us amateurs.

But now, we're faced with rolling bevels in our own build, on our own petard.

Back to first principles: We basically have two, parallel faces. A fair curve along one edge is known from the plans. We know the edge angle at several points along that curve and also that they are increasing -- slowly and smoothly -- at known points along its length. Hmm. So if we figure out (by a simple lofting) the offset each angle makes across the thickness of the piece and plot those points on their stations, we can draw a second fair curve on the second face. Plane the edge to meet the two curves and voila! The perfect curve, de-terrified.

Ply Scarfs

For various (probably trivial) reasons, we chose to scarf the ply sides together rather than use our usual butt-straps. Conditions dictated 8in scarfs for 3/4in plywood.

Now there are an endless number of jigs possible for this, but they take time, materials and brainpower likely exceeding the job itself (in our one-off case).

First we tried the method we used on SLACKTIDE... step each sheet back 8in, fix a 2x4 runner to our circular saw to bridge the 'steps' and, with the salient depth set to 3/4in, have at.

Having at means scoring along at about 1/8in intervals, knocking that thin wall out with the blade and, using intact steps to support the 2x4 and saw, side-sweeping the flat with the tangent of the blade.

This works, but is strenuous going. I took it in stride 16 years ago, but am huffing and a-puffing, now! Worse, unlike in SLACKTIDE, our present ply finished rough with this method.

Oh well, score the steps less frequently and use the planer to the depth they indicated. But, hmm... that turned out rough, too. What's more, I did 99% of the job with the planer by eye, then carefully removed the last smidgeon guided by the scoring.

Conclusion? Try it by eye as the sole means. Result? Better results in half the time with only a quarter the effort.

In short, I'd have save myself a lot of time and trouble, wear and tear if I'd trusted myself from the beginning. Sure, there's a learning curve, but no worse than more involved methods.

NOTE: We use LPU (Liquid PolyUrethane), a modern, gap-filling adhesive, for ply scarfs, so the matching planes don't have to be utterly perfect... just good enough.

*****

We d0 need to be clear on the principles and constraints involved. I'm not talking Blind-Man's Bluff, here. There is a certain amount of letting go and winging it, but that lies in our increasing control of our bodies first, and of our tools as extensions. 

We have the luxury to inform ourselves from past masters and present. We have the luxury to practice on scrap. We can Assess, Address and Appraise.

So... ready, set, practice, go and get 'er did!

Lofting Low

 

Everything should be made as simple as possible.

But not simpler.

Albert Einstein

Lofting Low

Being naturally lazy, I've spent an inordinate amount of mental energy on making boat-building easier. Over the years, whole swathes of the process have been successfully dumbed-down toward small enough bites for Anke and me to chew. Economical in time, space, money and materials.

One such swathe is is the process of lofting a vessel. 

'Lofting' is laying down the lines which define the shape of the vessel and some its components. All the individual lines need to agree with each other, meaning extensive cross-referencing and nudgings until they do. This is a finicky process, involving patience, focus and good spatial visualization.

Generally, this is done full-size or at some large fraction thereof. The resulting vessel is 3D (three-dimensional), but the lofting is generally laid down in 2D... done on a flat expanse called the lofting floor. Often, it was located in a loft under the roof of the building shed... hence the name.

Still with me?

Okay, let's take a survey of things we need:

• A lofting space - This is generally in addition to the construction space and preferably stays available throughout the build. The lofting floor should be out-of-the-way, amply sized, smooth, sheltered and hopefully warm.
  
  
• Esoteric skills - Lofting isn't rocket science, but neither is it run-of-the-mill. We need to understand the specification of points and lines as they relate to the plans, the techniques for laying them down, fairing, correcting and coordinating and further techniques for taking them up again to apply to our growing vessel and its parts.
  
  
• Special tools - The more complex the lofting, the more tools we will need. Splines, ducks, tacks, pencils (of various colors?), spiling (taking the pattern of a curved or otherwise complex shape) plus related tools... and so on.
  
  
• Time - A fair amount of it, especially if this is our first rodeo. Especially if the vessel's shape is complex. Especially if the loft itself must be built.

I can't count the number of times I've bemoaned this list, only to have someone tell me how simple and easy it all is. Only problem is that I've done it and it isn't.

Let's see what can be done to ease our way...

Simple Vessels in Sheet Materials

The first step is to simplify the problem.

Sheet materials generally lie flat or follow a section-of-cylinder or section-of-cone. Vessels built from them are a subset of shapes which - as a class - are generally much easier to loft and build.

NOTE: Sheet materials may also be tortured into compound curves but that ain't entirely simple, neither!

Simple vessels with fewer and simpler curves are easier to loft and build. In this post and lead image, I attempt a rough hierarchy of vessel shape complexity.

Lofting Space

Clearly, if we can take the loft out of lofting, we're ahead of the game.

Phil Bolger with Dynamite Payson popularized Instant Boats in their book(s) of the same name. A key feature is that the lines are laid down (lofted) directly on flat panels (e.g., bottoms, sides, decks and components) before bending into shape. Such lines are said to be expanded.

Following this practice, one eliminates the separate lofting floor. Time and potential errors are saved as most lines are directly cut to shape the panels (no transfer from loft to materials).

In our (flat and rockered bottom) builds, we've taken to building the bottom first, in sections which are finished, flipped and joined. While still flat, we use this structure as a building platform for bulkheads, sides and other components. Once ready, we assemble the structure building upwards from the bottom. This saves flipping a vessel that has been built inverted.

Esoteric Skills

By this point, the 3D shape of the vessel has been chosen and designed for low complexity. Required skills are accordingly much reduced. 

Spatial visualization is far less taxed. Cross-references are minimal and straight-forward. Curves are simple and simply faired. Corrections are mostly limited to point control (vs the correction and coordination of interrelated lines).

Design can go a long way toward easing or eliminating spiling. Box-Barge/Scows, for example are self-rectifying (if the edges meet, they pull themselves into square). Their parallel sides and dead-flat bottom sections mean 'house-carpentry' for most of the hull (no spiling at all!).

In TriloBoats, the use of whole and simple fractions of sheets mean laying out and cutting are held to the minimum, with attendant reductions in waste.

Special Tools

While a few special tools will likely be necessary in any hull shape more complex than the simple box, simplifying holds them to a handful.

In particular, simple curves allow stiffer splines that are generally three point curves (two control points - one toward each end - plus one somewhere in the middle. Unlike the more sophisticated tools for fairing complex curves, simple weights over a sharp corner suffice (of a plank, say, or paperback book).

Design can often help here, too - employing simple rectangles and arcs of a circle - to eliminate splines and rolling bevels.

Time

Everything discussed here has saved time. Time, time, time, time.

Lofting space comes 'free' with the vessel being built. This is (infra)structure right at hand (no round-trip to the loft, looking for a clue).

Simpler lines are laid down once with straight edge, simple spline and radius, and rarely 'taken up'. Cuts are made directly along these lines. Spiling is reduced.

At the extreme end (box-barge/scows) much time is saved in layout, cutting and squaring up the hull. Spiling, most bevels and all rolling bevels are reduced or eliminated.

Bolger never liked the term instant boat, but we can sure edge closer!

*****

Nothing I've written here is in disparagement of lofting or the complex end of vessel space. I love those Curvy Dogs! I respect those who lavish their skill, time, energy and passion in every aspect of their construction.

But like I said, I'm lazy. What's more...

I'd rather be sailing!

Wood Heat for the Lazy

Spike in the Log 

Pulled from the Log

EROEI – Energy Return On Energy Invested

Wood Heat for the Lazy

It’s often said that wood is the fuel that warms us twice. But that’s understated!

Lessee…

1. Locate, fall and limb tree (standing dead and dry).

2. Buck into stove-length rounds.

3. Split to various sizes..

4. Transport to home.

5. Stack (store) handy to stove.

6. COOK and/or HEAT.

7. Clean stove (periodically).

By my count, it warms us seven times! On our waterborne home, this omits fetching wood in from the woodshed. And I didn’t even mention greenwood seasoning (drying 2 to 3 years)!.

All this represents a considerable amount of energy invested in the energy returned for desired cooking and heating.

Similar to cost/benefit analysis, EROEI is the ratio of the amount of energy we get from a given energy expenditure; the bang for our energetic buck. Without doing any math, it urges us to think about our energy inputs, outputs and benefits in relation to costs. It’s an orienting concept. High EROEI is good; Low EROEI is less good. EROEI = 1 is pointless; EROEI < 1 is a downward spiral.

For fuels such as diesel, gas or electric, our personal EROEI may appear lesser, but money must be made and spent with all the energy investments that requires of us. The equation is more complex, perhaps, but pertains, nonetheless.

From our point of view, a few hours passed weekly in beautiful woods and useful exertion  in return for energy independance has been a good bargain. It has gotten us off our lazy butts and into the wider world. Our blood flowing and our backs strong. But as we age and our store of individual energy diminishes we’re looking ahead. 

What follows are a handful of approaches, resources and tactics aimed at increasing our return and reducing our investment for higher EROEI.

Smaller Volume plus Insulation

Insulation is a lesson we learned better late than never. Higher R-value hull and overheads with double-paned windows have become our standard practice. 

Now we’re looking to reduce volume. The smaller a space to heat, the less energy return is required, which in turn lowers our necessary energy investment (for heating, but also for row/sailing and maintenance).

In WAYWARD (our present boat), the living space is 20ft x 8ft x 5ft in the main, plus a trunk cabin and hatch that end up totalling about 1000ft3. The boat we’re now building for our dotage will be 12ft x 4ft x 4ft plus a small galley extension to total about 250ft3. 

We’ll have only a quarter the volume to heat!

Rocket Stoves

It’s said that the energy lost in woodsmoke is nearly half the total of unburnt wood. Rocket Stoves burn that smoke, reducing wood demand accordingly. With a quarter the volume to heat and (about) half the wood per unit of heat, we’re already talking around 1/8th the required energy investment for the desired outcome.

Furthermore, they reduce or eliminate energy invested in points 1-4 from our list above.

1. Target small dead limbs – Thumb to wrist size covers cooking to heating. This eliminates whole tree felling and brings the dead limbs of many otherwise living trees online. In our forests, there is a super-abundance of limbs in this range, both among lower branches and windfallen. As a bonus, our coniferous limbs are sap rich near the bole for extra energy density.
   
   

2. Process to length – All methods (see below) are much easier with small diameters than bucking sound wood. Since there is no stove box, we can use longer pieces, reducing the number of cuts.
   
   

3. No splitting! – This is especially helpful as long-fibered spruce, generally our most practical firewood, resists splitting (which make it great for spars).
   
   

4. Transport – Because gathering is such light duty, we can typically keep up by gathering a small amount on our daily ventures on shore, spreading effort over longer time. In our case, the heavy packs we’ve been using over treacherous footing constantly threaten strain or sprain… smaller loads are fail-safer.

These points are hard to quantify, but further increase our EROEI to a substantial degree.

Alternatives to Sawing

Sawing wood is hard work, even with a blade that is well sharpened and set (a process of considerable energy investment!). Nevertheless, it’s the least effort for bucking up rounds which are sound and of larger diameter, and/or of a tough species. For small diameters, however, other methods are faster and take less effort. As a bonus, since small stuff is less stable for sawing, the saw can skitter dangerously… other methods, while not carefree, are generally a degree fail-safer.

• Lop – A good set of ratcheting anvil loppers (for dry wood) makes quick and easy work of any limb within its range.
  
  

• Chop - With an ax, hatchet or hatchet/maul and a hardspot (stump or log) chop down perpendicular with a single strike on opposing sides (two, four or more according to difficulty) of a limb to create a weak spot (we’re not generally chopping through). Pull the end back to bridge between hardspot and ground and smack it with the back of the tool to break or use any of the following methods. It’s generally more efficient to first chop along the whole log, then break along in one go.

• Break - Depending on diameter, species, soundness and dryness wood can be directly broken by hand or across a knee, tree, limb, rock, etc.. Holding to either side and striking at the breakpoint impact loads that point for usually good results (use caution to preserve your wrists against that same impact!).

• Leverage - Leverage multiplies our power, greatly reducing energy invested. Look for a hard point and a fulcrum a little less than the desired length apart. Closely spaced trees or limbs work well, as do rock neighbors, crevasses and overhangs. Insert the stick with its end on the (further) hardspot and break point on the (nearer) fulcrum. Pry until broken. Sometimes it helps to break halfway, turn the stick 180deg and finish the other way.

• Whack Job - This one only works with punky wood, but is fastest and very easy. Find a hardspot, preferably with a sharpish edge (rock, say). Swing the wood like a bat to impact at your desired break point. Momentum snaps the stick on contact. As with an axe, use effort to accelerate the swing but relax before impact (ride the end of the swing) to reduce shock to your joints.

• Cudgeling - Again, pretty much for punkwood. Find a soundwood cudgel (usually about the size of a baseball bat), bridge the victim, and whop it in the middle to break. Watch out for flying ends!

All these methods can be mixed and matched as convenient. The ‘tool-less’ methods are especially helpful in the field for impromptu picnics, and help reduce long wood for a smaller, safer fire.

As you can see, the more brittle the wood, the easier it all gets. Which brings us to…

Punky Wood

Punky (rotting) wood has lost a portion of its energy content to oxidation… in effect, it is pre-burnt to a degree. But a goodly amount of energy remains. 

The benefit is that fermentation has weakened the longitudinal fibers, leaving it easy to break by any of the manual means or with ‘found’ tools. In minutes of light effort, armloads of firewood can be gathered with neither lop, chop nor saw. No tools to sharpen, transport or lose!!

While gathering, we look for the rather broad ‘Goldilocks’ point: not too firm, not too far gone. Light and dry. Well-aired in place or partially elevated above the ground, they dry quickly. The woods are rife with low-hanging dead- and fallen limbs in this state. Close to our fire, boat or dory is a plus.

Punkwood is consumed quicker than sound wood. Thicker diameters can be used to slow and cool combustion (which is proportional to engaged surface area). Where sound wood thin enough to break by hand burns away quick and hot, we can go for larger diameters in punky woods that burn cooler and last far longer. This is especially useful for even heat of a cool evening. Thick ‘uns also take up less storage volume than the equivalent mass in small stuff.

In our parts alders line much of the coast. This quick-growing ‘hardwood’ produces many dead limbs which go punky in short order. Other species such as poplars, aspens and birch are similar.

A couple of cons with this approach…

Compared to sound wood, punkwood requires more volume to transport, tend and store for any given amount of heat. Greater throughput means more ash and its clean-out. These energy investments weigh against its other gains.

While punkwood dries quickly, it absorbs water just as readily. In wet weather (which includes most of winter), it’s often too wet to use.

Still and all, for much of the year, it requires substantially less energy invested for energy returned. So low, in fact, that ‘bouquets’ of punkwood from our daily walks generally supply us with all the summertime wood we need.

‘Spikes’

Spikes are the pitchy roots of limbs from a rotten conifer trunk of pitch rich species (e.g., some pines, spruce, fir?). The pitch is energy dense AND preserves the spike AND waterproofs it… spikes are only ever surface-wet and dry quickly. The rest of the limb has usually rotted away leaving stove-length pieces.

Once the trunk of a fallen tree is fully soft, one can walk along it and harvest the limbs, pulling the spikes like carrots. Or walk along many creeks and beaches and simply pick up spikes (which don’t float) from trees long gone. A few days in the sun or behind the stove and good to go.

Bark

Beachcombed fir bark is a windfall, as fir only grows far to the south of us. Ranging from 1 1/2in to 6in thick and up to 6ft long, it is easily broken to length. Quite resinous, it resists absorbing water and dries quickly in any case. It charcoals quickly but lasts long, perfect for warming on a rainy day.

Alan and Sharie Farrell used mostly fir bark, especially in their later years. It became scarce as British Columbia logging receded, and this became quite a problem for them as time went on.

Fir bark works great in a fire-box. We haven’t yet tried it in our Rocket Stove, and I have my doubts. Too smoky? And the Rocket principle is a hot burn. 

But there are other applications…

Coppicing

Coppicing is the practice of cutting a swift-growing species (such as alders, willows, poplars and many fruit trees!) back to a stump trunk. New limbs spring up in their hundreds for sustainable harvest. It was commonly used for prolific woodlot fuel production on farms and commercial stands.

This approach looks to be a promising option for favorite spots…an arboreal guerrilla garden!

*****

There are many things we’ll miss about our current wood-range with oven. But I gotta say, its low EROEI won’t be one of them.

We’ll just have to find other ways to get our exercise!