s/d Puffin, PA 4792 CA

She's a Mertens-Gossens D4* (EX**)
* The D4 is now called the D5.
** the EX can be for extraordinary, extravagant, excessive, or extreme. Take your pick.

The D4 is a classic. Think of a "dinghy", and chances are, you're picturing a D4 in your mind. Jacques Mertens, the designer of the D4, will tell you that there have been thousands of downloads of the free plans. Had Carl Sagan said that there were "billions and billions" of them afloat around the world, he might not have been too far off the mark.

Todd Dunn, webmaster of The Denizens of The CWSWBB, has a Page devoted to building a D4 with 1" blue Styrofoam®, and fiberglass. My uncle John, built one by constructing a 1"x1" skeleton, wrapping it with Visqueen®, and fiberglassing it. When the glass set, he removed the frame and had perfect little tender for his Tartan30. Robert Taylor built one from sheet metal. Our Dinghy Cruising discussion group member in Turkey, Ozkal Ozsoy, built a very good looking "standard sailing version." (He followed the plans.) Ozkal then formed Tekne, a discussion group in Turkish. He and several other Young Turks are assembling a D4 flotilla.

There seems to be no end to what can be done with them.

Join the growing ranks of small boat builder/sailers at Yahoo! Dinghy Cruising. Show your own boat, ask questions, pour over the Bookmarks and Files. We're a very lively and helpful bunch of messabouters.

Fellow D4 builders and their links

"Boo Boo the Dinghy", Mike Saunders, Dinghy Cruising Moderator, Allaround Redneck how-to website.
"Highland Lassie", Keith Beymer, very nice how-to website.
"Yertle the Turtle", Shawn Payment, should be required reading for the first-timer.
Ozkal's "No-Name?" D-4, Ozkal Ozsoy, Turkish and English how-to website.

The "EX" stands for Experimental and Expedition.


The boatbuilding disease came on slowly as a remedy for a general middle aged malaise I'd been experiencing. I was very involved with model railroading, going to train shows with my train buddies, building an extensive layout in my basement, and... forseeing my future forever ensconsed in my dank basement.

Out of the blue, my pal Bob "Boob" Dougherty, several years my senior, chucked it all and ran off with a babe and a boat. A boat seemed like a good way to get out of the basement.

Puffin developed as an "upgrade" from my original lunacy of building a sailing kayak to hopscotch across the North Atlantic to Europe. I envisioned Puffin as a long-range sailer, and/or a lifeboat, hence the need for storage space and sleeping accomodations. Luckily, my wife Lisa raised an eyebrow at me, suggesting that perhaps something a bit bigger might be more appropriate to cross The Ocean. "Now there's a thought." The ol' Dawg was crazy like a fox. Huh?

Some people can't leave well enough alone!

She's built from 1/4" Luan plywood inside and 1" Styrofoam® outside for flotation. Because the flotation is outside instead of under the seats, as in most D4s, there is 6'6" between the anchor locker and the transom; allowing ample room to lie down.

We live in a small renovated factory building, 24'x56'. Downstairs we have a kitchen/dining area/livingroom, and Lisa's studio. Upstairs, there's the "real" livingroom (22'x30') and our bedroom and bath.
I started by clearing out all the useless clutter; you know, the sofa, the chairs, coffee tables, lamps. The sofa turned out to be a nice worktable, so I laid a sheet of plastic on it, then a piece of plywood over that to keep all my "fixin's" from tipping over.

As you know from doing your D4 research and downloading the free plans, the D4 is assembled upside down. For this initial phase of construction, I setup two sawhorses with a couple of 2x4's spreaders to carry the sides. The links at the bottom of this page show several other guys building the basic boat.

By way of a "how-to", I will say this though, It's important to get the sawhorses LEVEL so that you don't build a permanent wrack in the hull as you stitch and epoxy it together.

Here's the cradle I set up for the right-side-up work. [D4cradle.jpg]

I started out routinely, following Jacques' excellent step-by-step tutorial until the basic boat was assembled. Then added deck beams and cockpit lockers. The main beam at the forward edge of the cockpit is laminated plywood 3"x1½". The beams in front of and behind the daggerboard case are ¾"x1½".

"Gilding The Lily"           &           "Uh-Oh, Caught!"
(Hey! Philly is HOT! in August, even at 6:00AM.)

The deck was laid down, marked and roughly cut to shape. Epoxy was applied everywhere it would contact the hull. Then it was strapped down and glued on. Afterwards I crawled inside to fillet and tape all the seams and beams. The deck was then trimmed along the edges of the hull. The mast tube is a ¼" of fiberglass laminated over an 1½" PVC pipe mandrel. Several layers of plastic sheeting were wound on the pipe prior to 'glassing in order to allow some clearance for the 1¾" mast. I suppose I could have just used a piece of PVC for the mast tube, but I wanted to play at making a substantial lamination of pure fiberglass. It worked GREAT! On Puffin it's kind of necessary too. Since I can't actually see the mast step, all I have to do is drop the mast down the hole; lines up every time.

The toerails are mahogany. I envisioned a proper lifeboat as having something you could brab onto after you got tossed overboard. (Besides... they look kind of cool.)
The lumberyard let me have a 12' 1x4 for cheap because it was "stained". No big deal really, since I planned on painting it anyway. So, I ripped it, laid out the handhold openings, drilled holes at each end of each opening, sawed out the centers, cleaned up the holes, then routed out roundovers inside and out. I cut a rabbet into the lower edges so that they would sit on the sheer.
Getting the little beasties to hang on to the boat was a "challenge" to say the least. Who was it that said? "You can never have too many clamps." I used all my bar clamps, pipe clamps, ratchet straps, and when those weren't enough, I rigged up some Spanish windlasses. (Persistence pays off!)

I had enough mahogany left for the bow board. Because of the curve of the bow, I had to cut the piece to the bow curve and spline the leftover piece on the top.

Next, I turned my attention to the keel. Having departed so liberally from the standard D4, it seemed quite natural to add a full length keel.
Three layers of Luan glued together. Marked for the garbord rocker, then glued and taped to the hull. The entire outside was then epoxied.

The foam was glued with some sort of bathroom tile mastic with a notched trowel.
The lines along the corners are layout lines for rounding over the radii.

Fairing went as well as might be expected. Sand, fill, sand, fill, until it looks and feels "right".
Painting the hull was a labor of love, but the effort was worth it. It looks like a Gelcote finish.
I'd faired the fiberglass with epoxy and phenolic bubbles, then sanded. Rolled on a coat of primer, faired again, then sanded most of it off again.
Then I reprimed, and started painting, and painting, and painting. (I didn't know about highbuild primer then. It was also my first attempt at making something reeeely smooth.) After three coats, I wet-sanded with 220 paper and applied three more coats.

The charcoal grey deck wasn't nearly as difficult. I wanted a nonskid surface. So after glassing and fairing the deck, I applied primer and two coats of grey. Then, prior to applying the top coat, I cut a corrigated cardboard stencil to cover half the deck. Once it was fitted around the edges, the centerboard handle, mast and anchor locker, I cut out the center, leaving only a 3" border of cardboard. I drove ¾" drywall screws into the stencil from both sides, every 3"s, to elevate it above the paint.
I laid on the last coat of paint, rested the template over half the deck, and dusted the wet paint with micro-bubbles. Then I flipped the template over to the other half and dusted it too. Atfer the paint dried, I rubbed away and vacuumed the loose beads.
The final result looks "Mah'vellous!". From certain angles, the deck has a slight sharkskin sheen. "Simply Mah'vellous!"

The anchor locker hatch is the only piece of brightwork (other than the rudder and daggerboard).
The top of the hatch is strip-planked mahogany, fiberglass and three coats of polyurathane. The frame is mahogany. There's a half-lap joint around the opening. I spread latex caulk around the laps and covered them with cellophane (to keep them from becoming glued together), then closed the frame and let the caulk set. After it set up, I removed the cellophane, trimmed the caulk that had seeped out, and had a watertight seal around the hatch.

The second-hand Optimist sail wasn't cheap, but when I was told how much used spars cost, I fell into a dead faint. When I regained consciousness, the kid at the sailboat store let me Zerox the page of OptiMaxII specs. I bought 6061T6 aluminum tubing from a supply house and an assortment of Harken and Ronstan fittings from West Marine.
The mast is 1¾", the boom is 1½", and the sprit is 1".
The whole shebang cost about a third as much as a used rig.

Since these pictures were taken, the rigging went through an upgrade. I removed the sail ties, milled slots in the spars, and installed sail slides to ease raising and lowering the sail. In retrospect, it's all too complicated.
"Someday", when I get time, I'll convert to a Junk Rig.


My good friend Bill Grumbine invited me to launch Puffin at Lake Nockamixon. Bill is 6'6" tall and "corporially gifted". He stuffed himself into Puffin for a sail, and bravely proved that she can handle at least 350lbs. with room to spare.
See how nicely she settles on her lines.

Bill is building "Black Swan", a Selway Fisher Skylark 14, similar to the GFB-16 seen in the Sep/Oct issue of Boatbuilder Magazine.

A note before moving on.
If you're thinking of building a D4, I heartily recommend buying the full set of plans. They're beautifully detailed, include full-size patterns for those who don't want to loft the lines themselves, and notes describing materials and sources for the spar hardware.

Here's a belated shot of Puffin's foils.
They're covered with several coats of epoxy, no glass, and three coats of Minwax Helmsman Spar Urethane.

"Someday" arrives...

Late Summer 2001

By way of avoiding yet another sanding session on Albatross, and in preparation for the first Yahoo! Dinghy Cruising Messabout, I decided to sew her a new outfit.

I began by studying PRACTICAL JUNK RIG intensely and designing a sail.
Then I updated my Puffin model.
Why bother updating the model you ask. Because had I not spent some time on the model, I probably wouldn't have noticed that the CE was moved forward considerably until I was afloat and struggling with an unruley rig.

I bought 4 oz. Dacron from Sailrite. After I laid out and cut paper patterns for all the panels, Lisa and then Brian helped me sew the sail together.
All the stitching is done with a zig-zag stitch. The side seams are simple hems. The batten pockets were first folded and basted, then sewn to each other, amounting to a felled seam for the battens. They're four layers thick, two on each side of the batten. The battens are 1/4" fiberglass rods I found at Walmart in the bicycle department. They had a little orange pennant on them. The upper and lower hems have bolt ropes installed to slide inside the yard and boom.


That was just the beginning. She needed a new mast, yard and boom.
For the mast I borrowed a 10'x1.5" aluminum pole I'd given to Lisa. It's sleeved to take apart in two 5' pieces. To this I added a new 6" masthead, also sleeved, copied right out of PRACTICAL JUNK RIG. The new rig required moving the mast tube that goes through the deck back to the forward end of the daggerboard slot to maintain a CE similar to the original rig. Running out of time to be ready for the Messabout, I installed the new mast tube and capped off the old one instead of removing it. Who knows... I might need an alternative mast location someday.
The yard and boom are fabricated from a painter's 6' extention pole. The fiberglass outer half made the yard, saving some weight, and the smaller diameter aluminum inner half made the boom. The boom doesn't need to be terribly substantial anyway. They're both slotted for the bolt ropes.

Here she is at the Messabout...  [puffinjunk03.jpg]

I finally got around to building a pair of oars.
These are the second pair I've built; simpler construction and slightly more elegant. The first pair can be seen at: "A Pair of Oars"

Another improvement built since the Messabout is the "Cary hinge". Ted Cary in Florida, (sorry I don't have a link), designed a rudder hinge that eliminates the "pintles and gudgeons" problem. The original is wood and seatbelt strapping for the hinge. The ingenious and unique feature is the dovetail assembly. Two parts of the dovetail get installed on the transom and form a slot, the other part has the hinge on it(and the rudder.) The rudder slides into the slot.
I saw this on Boo Boo The Dinghy and was immediately impressed.

Mine's stainless steel and actually lighter than the equivalent in wood.
1" square tubing...

Cut and bent to telescope...
6" cutting discs to rip the parts, bench vise to bend to shape...

New gudgeons...
bolted on with with hex drive bolts and Nylock nuts...

The strip spring holds the pintles...
but allows the rudder to be unshipped from the hinge...

Final step, slotted to reduce weight...
A slim hardwood wedge will allow adjusting the rudder height.

Upcoming improvements...

The tent...
The gimballed stove...
The motor!


That would be telling. But rest assured, it won't be ordinary.

April, 2002

Puffin goes to another messabout; this one in Alabama. I had a great time and learned a lot about my little bateau. The Cary hinge worked great! My oars finally got "installed" so to speak. Sometimes the simplest solutions work best.


I'd brought along a drill and some fiberglass rod bits to fashion thole pins for the oars. After installing the thole pins and rowing my way offshore, the pins walked out of their sockets and jumped to their watery demises. The oars remained aboard though; the bungie cords being all that was needed in the first place. (Should have remembered the KISS principle.)


The other thing I learned is that she's too cramped and too complicated. Six running lines to the masthead? You gotta be kidding!

Recent developments prompt puffin pg. 2 a completely new Page.

Click on this little shack anytime you want to go "Home".[IMAGE]

Got any questions or comments? [dawg1email.jpg] Click on Cool Dawg's nose to Email me.

Copywrite © Alan "Maddog!" MacBride 2001
Most recent Revision May 06, 2002