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View Full Version : Ten Years of Hard Use, Exposure and Neglect -- What Worked and What Didn’t



Bob Smalser
07-15-2011, 9:17 PM
Over a decade ago I built the John Gardner-drawn 12’ Dion Punt below to use for swamp-logging in beaver ponds; a tender for setting the tongs and chokers used to grab the logs. The advantage of this design is that beaver ponds are full of stumps you often can’t see because of the dark swamp water, and they regularly hang up heavily-loaded conventional skiffs so badly you have to get out and push. According to Gardner, this boat was patterned after large cranberry bog punts used to transport heavy loads that sometimes included the draft horses they were towed with, and is purposefully more buoyant in the bow than in the stern. With this boat, when you get hung up on an obstacle, you merely move to the rear oarlocks and row off…without problems…one of those rare, “Voila!” moments, well worth the two weeks it took to mill the lumber and build the boat.

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Boatyard owner Fred Dion designed and built the first one of these in the 1930’s as a tender for his two marine railways in Salem, Massachusetts, marine railways also having underwater structure prone to hanging up skiffs. The scantlings on this boat are extra heavy for stability, impact resistance and all-around commercial use. This is hardly a sport boat, as it weighs over 300lbs when wet. I followed the design almost exactly, only substituting Western Red Cedar over Douglas Fir for the original Eastern White Pine over White Oak. Not only has this boat been used hard, when not being winched from the water and onto a heavy-equipment trailer behind the skidder, it has lived at a mooring out in the weather 24-7-365. When not in use, we simply let it fill with rainwater at its mooring and even freeze in the ice as less work than winching it out regularly. You can see the average waterline indicated by the white algae stains on the boat’s sides. Further, the only care the boat has received in the decade+ it’s been in the water or moved around with heavy machines are minor topside paint touchups to protect it from the baking summer sun here. Finally getting around to beaching it for proper repair and repainting after a decade+ of abuse is a good opportunity to study which boatbuilding techniques worked well…and which techniques did not.

The Prize.

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A migrating beaver family dams up a likely stream bottom at the end of a forested basin; the water rises and drowns the trees, which eventually rot off at the base and fall over. Over time the dam silts up and becomes a permanent pond, with some centuries-old dams a hundred feet long and forty feet thick looking like they were made using a bulldozer. The cottonwood, hemlock, willow, alder, maple, cherry, crabapple and other non-durable woods rot quickly, and along with tree litter from the surrounding forest, become the deep humus on the pond bottom. The more durable Douglas Fir and Pacific Yew become the mat of slowly-disintegrating snags floating on top of the water, and the cedars eventually waterlog and sink to the bottom. In these three recovered, old-growth cedar sawlogs bucked to 12’ above, there are (among other uses) around a thousand linear feet of vertical-grain siding custom-milled to match that on old houses, and represent a substantial return on investment.

Western Red Cedar. Often maligned as too soft and too brittle for optimum boat planking, I find in the 7/8” thickness used here to be incredibly tough, durable, resilient and easy to work. In fact, if I ever build another of these punts I’ll use either Western Red or Alaska Yellow Cedar in a slightly thicker scantling for the transom, bow stiffener, guards and even the inwales instead of Douglas Fir. Both cedars are more rot resistant, hold paint better, don’t check when left unpainted in the sun, and in collisions and abuse don’t split and splinter anywhere near as easily. It’s like hitting a stump with a bag of sand as opposed to a caulking mallet. Nor do I find Western Red to dent easily when properly coated; it tends to bounce off instead. That it doesn’t hold screws well can be fixed by saturating the pilot holes with epoxy thinned by solvents or heat before driving the screws.

Rough-Sawn Lumber.

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I milled the lumber for this boat to Gardner’s exact scantlings with an appropriate shrinkage allowance without thickness-planing it, and airdried it for two years before use. The rough surfaces worked very well as a key for paint, bedding or fairing compound, were easily belt-sanded in the few places where smooth is desirable, and not having to run all that lumber through the planer while fussing with finished thicknesses saved a couple days in construction time.

Second-Growth Lumber. I had a few pieces of high ring-count, old-growth fir I used for the transom, inwales, bow stiffener, and thwart knees…otherwise all the cedar and fir was second-growth, generally 8 rings to the inch or better, and vertical grain from large, mature, 80-year-old trees. I found no advantage at all to the old-growth in resistance to rot, checking or splitting. Of the three knees I replaced because of rot, one was old-growth…and the part I’m having the most trouble with is the old-growth, quartersawn, Doug Fir transom, which doesn’t match the seasonal stability of the similarly-cut cedar sides, and accordingly, has minor splits in two places requiring repair.

Hot-Dipped Galvanized Fasteners.

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If yours is to be a fresh-water boat, they can save you significant money over bronze or stainless providing you take some precautions. Bed the pilot holes in thinned epoxy or red lead and goo, and they will hold up better than those on the left in the photo. I was in a hurry, only bedded a few pilot holes, and a decade later you can easily tell which ones. Skip those steps and they rust like their counterparts on the right. Where you can use them, galvanized steel fasteners are a distinct advantage come repair time, as a common brace chucked with a screwdriver bit backs even the rusty ones out easily. In turn, the heads of softer bronze and some stainless grades like to strip, and bronze screws twist off much more easily. Depending on boat size and how it will be used, the cost difference between metals can be significant. The price ratio between hot-dipped galvanized to 18-8 stainless to silicon bronze is typically 1 to 3X to 5X, and this boat used a dozen or so boxes of #10’s, #12’s and #14’s from 1 ½ to 2 ¼ inches long.

For greater economy, the boat could be nailed together and have the same longevity, it just wouldn’t be as easy to repair. I prefer bronze ring-shanks because they are soft…a pry bar and a hacksaw blade make disassembly almost as fast as a brace and galvanized screws. Once cut, the head is driven out with a punch and the pointed stub is driven into the wood to stay. Stainless ring-shanks or box nails aren’t anywhere near as easy, and are almost as expensive. Galvanized boat nails are also an option, but nails don’t bed as easily as screws and won’t last as long as a well-bedded screw.

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And if you like to use a brace for screw chores as I do, I recommend you find an 8-incher on eBay for driving to supplement the 10 or 12-incher you probably are using for removals. Few out there value braces as user tools today, and even the rare ones go relatively cheaply. Smaller, lighter and surprisingly handier, the tiny 8-incher replaces the Yankee Screwdriver entirely in many instances…only with much more power, more precise control, and less carpal pain…plus saving you the step of rigging a different tool for many tight spots.

Rope Bumpers.

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They can both lengthen the life of the sheer guards by providing padding from bumps, and also shorten the life of those guards if you don’t properly bed the screws or marline holes used to mount the rope. I failed to bed all those #6 stainless screws, allowing lots of water ingress from the slow-to-dry rope…and the Doug Fir guards rotted well before their time.

Continued…

Bob Smalser
07-15-2011, 9:17 PM
Ramin Dowels.

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I used some store-bought Ramin dowels to reinforce a few places in the cedar instead of my usual practice of using bronze rod drifts. Ramin (the straw-colored, big-box store dowels that have an open grain similar to mahogany) isn’t a durable wood and I expected they would be mush by now. But they held up perfectly, probably because they were set in epoxy. I still recommend silicon bronze or marine brass rod or boat work instead of store-bought dowels, but it’s good to know you can squeak by with a shortcut now and then when you run out of something…thanks to epoxy.

Sawn Knees.

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A common design, especially for utility skiffs, but a poor one. Too much end grain to sop up moisture compared to the face grain of laminated knees (top) or knees taken from grown crooks. Treat all that end grain with CPES or thinned epoxy, and use bedding compound for both the knee faying surfaces and the fasteners:

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In these sawn quarter knees in the stern, I used my worst fir, treated the faying surfaces with thinned copper bottom paint, bedded the frame head poorly in bedding compound, and failed to bed the end grain and the fasteners entirely. The result was all that unsealed end grain wicked up available moisture, the topcoat of sealant and paint held it there until both stern quarter knees rotted and their fasteners rusted, as did one thwart knee…in spite of the old-growth fir it came from. Fortunately I caught these before they took too much of the transom with them. The bow knees didn’t rot because they rode higher out of the water when the boat was swamped, and remained drier.

Knee Replacement.

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Having good patterns makes for fast and efficient work. I lay the three rotten knees out on a scrap of second-growth, vertical-grain Doug Fir 2X12…make the longest beveled cuts on the compound miter saw to separate the three blanks…

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… screw each knee to its’ blank so as to use a stiff hand saw to make the smaller bevel cuts, using the old knee itself as the index.

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This is a much faster technique than transferring each fussy angle using bevel gages and pencil marks to a power saw, which won’t easily do those short, frame-head relief cuts anyway.

Continued…

Bob Smalser
07-15-2011, 9:18 PM
Sheer Guard Replacement.

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Again, using the old guard as a pattern, the contractor’s saw is set up to mill a couple of VG Doug Fir 2X4’s to get out new, 5/4 guards…

http://pic20.picturetrail.com/VOL12/1104763/9745605/397619701.jpg

…followed by the simple tasks of ripping to width, resawing to thickness, and making the three bevel cuts; with cleanup and edges quickly eased using hand planes. The v-groove will hold the new rope bumper and was used because it will hold a thicker layer of bedding compound to seal the screws mounting the rope than the original cove did. And the bottom edge of the guard is sharply beveled so as not to hang up on things when the boat bobs in a swell, which is also the reason this boat was designed with smooth rather than lapped sides.

Preparation.

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Before installing the new parts, the boat is power-washed with Tri Sodium Phosphate detergent, belt and rotary sanded so that all paint surfaces are clean, well-scuffed, and all chip edges feathered and corners eased to hold paint. The boat is then vacuumed, and as much of the old joint goop chiseled and pulled out of the seams as possible. Then the joints like these frame heels and other exposed faying surfaces…especially those involving end grain…are treated with CPES or thinned epoxy, which wicks nicely into the joint seams without acting as a glue to complicate repairs in the future. Exceptions to epoxy treatment are the cotton-caulked planking seams, which get only lead primer and seam compound so the cotton will remain flexible and act as a gasket instead of a hard wedge.

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Reparable wood damage is fixed using thickened epoxy, then faired…

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…and the new parts are installed, here using thinned Far West Paint’s red lead substitute (it uses yellow lead chromate instead of red lead tetroxide) on the faying surfaces, as well as a general primer. Vulkem 116 poly sealant is used on all faying surfaces after priming, and also in all screw holes.

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New and old parts are blended and faired using block plane and rasp, reprimed as necessary, and every seam, check and void is filled with sealant and struck off before final painting.

Continued…

Bob Smalser
07-15-2011, 9:18 PM
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Using a farm jack as a third hand to accurately spring the guards into place for fastening. All parts that require bending into place benefit from at least a couple feet of extra length for leverage, whether you are steaming them or not. As the jack raises the guard into alignment with the sheer, the multiple C-clamps lock it into place before drilling pilot holes and fastening. Once fastened and while the clamps are still in place, the original copper framehead-to-side-and-inwale rivets are tightened up as necessary using a small, ball-peen hammer.

Red Lead Substitutes.

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Not having a source for red lead a decade ago, I used 50-50 thinned copper bottom paint (the cheapest Fisheries Supply carried at the time) to treat the faying surfaces and cotton caulking of this boat in place of red lead. You can see the light green under the dings. It worked well. Now, after an evolution of making my own red lead, I’ve switched to Tukwila, Washington’s Far West Paints who make a “red lead substitute” using lead chromate. The stuff is yellow instead of red, but I’ve used it before on metal surfaces where it’s considered an excellent primer, and am confident it will work just as well on wood. The topcoat will be a Kelly-Moore alkyd enamel for full compatibility with the primer, one of the last alkyds made as more and more manufacturers discontinue traditional, oil-based paints in favor of latex. Both paints run around 40 dollars a gallon.

Hardware Store Sealants.

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The common, gun-grade caulks used as bedding and seam compounds all worked fairly well. Unlike traditional linseed oil and chalk compounds, none attracted mold and all remained perfectly flexible after a decade in the weather. The cheapest acrylic door and window sealants (top) pulled out the easiest, although none fell out in service as they were well-covered by paint. The butyl rubber (bottom) was more tenacious, and the most tenaceous is the polyurethane (currently on the boat), which is rated for continuous water submersion and is the most compatible of the three with oil-based paints. All are easily reefed from wet planking seams when the time comes…the acrylic perhaps too easily.

Cotton Caulking.

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I checked the cotton in a few places and found it to be in fine condition, even though these side to plank-end seams didn’t get enough copper bottom paint for saturation. There is no substitute for getting the seam horizontal where you can dribble paint into the seams via gravity. I originally caulked these seams in the vertical, and should have used a piece of tin as a dam to wick in paint more thoroughly.

Bottom Stringers.

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The fir bottom stringers or runners are worn and gouged in places to half their original thickness, and I really should replace them. But in seasoned Douglas Fir that’s a difficult, kerfed bend in the steambox, and I elect to repair them in place using epoxy worked into the cracks and thinned using a heat gun, followed by more epoxy thickened with cabosil to fill the collision damage, with care taken not to glue them to the cross planks. Overall, the stringers did an excellent job of protecting the softer planks. The remaining carvel seam caulking is also lightly tightened.

Bilge Pumps

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I originally mounted a small Rule plastic pump in a basket and kept a 12V battery in the dock box to pump the rainwater out before use; a really poor idea. It took over an hour to pump the boat out when full, the tiny pump routinely clogged with tree litter from the surrounding forest, and carrying the battery back and forth to a charger was a pain. I’ve since changed the heavy battery out for a lighter, 2-stroke, 1” dewatering pump that empties a boat in 10 minutes, and will permanently mount a salvaged Merriman bilge pump I rebuilt for when there isn’t enough rainwater to bother with the gasoline pump, which is made by Koshin of Japan and uses a high-quality Mitsubishi engine.

Continued…

Bob Smalser
07-15-2011, 9:59 PM
Finishing Details

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Naturally it rains in the middle of my last coat of paint, when the weatherman said it would hold off until midnight. But as a timberland guy in forest fire country, I’ll take all the rain I can get in July and August.

To be Continued…

Reference.

John Gardner. Building Classic Small Craft. Camden Maine: International Marine Publishers. 1977. p12-15.

Mac McQuinn
07-18-2011, 8:16 PM
Great Post Bob! Look forward to the continuation.

Mac

Jim Underwood
07-19-2011, 5:16 PM
Bob,
I read this a few days ago, and thoroughly enjoyed your account. I too look forward to the rest of the story...

Bob Smalser
07-20-2011, 8:13 PM
http://pic20.picturetrail.com/VOL12/1104763/9745605/397776165.jpg

But as someone who burns a lot of wet slash, I have some tools useful for drying large objects you may not.

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Galvanized carriage bolts applied below the waterline…like these mounting the bilge pump…get a coating of sealant to protect the zinc from the acidic cedar and also a wrap of cotton beneath the head to act as a watertight gasket. If this was a warm-water boat, I’d also apply some thickened red lead to the cotton. The bolt holes have been treated with CPES followed by red lead substitute primer.

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I elect again to use #6 stainless screws to mount the rope bumper, only this time with a lot of sealant and only a few screws. A helper to stretch the nylon rope and hold the stretched rope in place with clamps is useful before fastening. Phillips-head screws are easy to run in until the heads bury in the rope to hide them.

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The salvaged bronze bilge pump ($30-50 on eBay) is mounted so the discharge spout can be rotated inboard, and the entire pump can be removed for cleaning and servicing without removing the mounts. The strainer-foot and lower end cap unscrew and the pump lifts out. Usually all these old pumps need are their plungers rebuilt with new leather to return them to full serviceability.

Changes I’d Make.

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Gardner specified sides, bottom and transom of 7/8” pine, which I duplicated in local woods…but in hard use I’d prefer a bit more thickness in the transom, both for strength and looks. I’d go to 1 1/8” in Douglas Fir or Alaska Yellow Cedar and 1 ¼” in Western Red Cedar, using epoxy to reinforce the screw pilot holes in the softer red cedar.

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Gardner landed the sawn thwart knees on the inwale as well as the boat’s sides, and as a result there wasn’t room for two adults to sit side-by-side. I made them slightly smaller and landed them only on the sides, but if I build another I’ll laminate the knees in place, landing them on the frames. This would be a much stronger assembly with less end grain to seal and screw fastening into face rather than end grain.

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Last, I’d double plank the bottom, at least from the tuck to the stern. Unloaded at a mooring the rear planks ride clear of the water while their tops bake in the sun. Hence by the end of our dry summers they become weepers the moment the boat is loaded. They take up fast enough, but weepers can be disconcerting to passengers.

The Grand Prize.

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Here’s one I need a bigger machine for. Three to four feet in diameter and almost a hundred feet long, laying so the skinny end rides out of the water and grows vegetation.

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And finally, this one is four to five feet in diameter and 120 feet long…somewhere around 50 tons of waterlogged cedar, waiting patiently for me to figure out how to retrieve it.


Reference.

John Gardner. Building Classic Small Craft. Camden Maine: International Marine Publishers. 1977. p12-15.

Aaron Berk
07-25-2011, 5:54 PM
This is an absolutely awesome thread.

I've never been in this part of the forum till today, and this is my 1st thread to read.

I'm inspired and now want a boat. LOL

Thank you Bob.

Richard Wolf
09-05-2011, 12:51 PM
Nice tread Bob, great restoration.

Tom Giles
09-25-2011, 10:17 AM
I thoroughly enjoyed this thread. Thanks for taking the time to share.

Scott T Smith
09-25-2011, 10:41 PM
Fascinating post and project Bob. Thanks for sharing.

Scott

Sam Murdoch
01-20-2012, 5:25 PM
What a great post! Pretty boat, and lots of really useful info on what works and what doesn't. Excellent, thanks for it.

Larry Lilly
01-24-2012, 3:48 PM
Great story

Would a D9 Cat handle that log?

I man, you need some horsepower and it doesnt look like that log is ever going to float again.

Bob Smalser
01-25-2012, 8:43 AM
Great story

Would a D9 Cat handle that log?



All 50 tons of it? No.

The log will have to be bucked to length to come out. One problem of several is finding a hydraulic chain saw with enough power to handle a 36" bar. Another is there isn't enough water there to break the suction using a combination of floats and seasonal water levels.