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Senin, 14 Maret 2016

BoatBuilding A Mad Mothist does a Bottom ectomy

On modifying my Classic Moths Ive rebuilt decks, rebuilt daggerboard trunks, added buoyancy tanks, glassed interiors, but Ive never grafted a new bottom onto an existing Moth - performing a bottom-ectomy so to speak. British Mad Mothist, Jim Champ, former Cherub sailor, dinghy historian, amateur dinghy designer, current International Canoe sailor, and webmaster of the International Canoe website is doing just that to a fiberglass Skol he purchased.

Ill let Jim explain his project in his own words.

"The back story is I picked up this 1970ish Skol Int. Moth because I needed something to sail while a health problem was stopping me sailing my Int Canoe in most conditions, and besides, Id always fancied one. The fact that I am now about 5 stone too heavy even for a vintage Moth didnt deter me.

Anyway, the boat came out of someones garage roof, and I completely failed to spot, under the layers of dust, that at some stage the boat had been sliced off at the waterline and been given a new wood bottom, replacing the original glass. This was no problem until after a seasons use it became apparent that the wood bottom had been allowed to rot back in the day, and some crucial bits were now leaking badly as the water had re-penetrated.

So I ended up cutting off the wood bottom, and Im now building a new one, and learning about cold moulding while I am at it. Shape wise its roughly based on a Cherub I drew in about 1974 but could never afford to build.

What have I learned from this project? Not to be afraid of cold moulding, and when you do it use plenty of strips. I originally was trying to use quite large panels in order to minimize the number of accurate edges I had to cut, but actually getting the sides of the strips accurate is surprisingly easy given a small sharp plane and a block and sandpaper. Its definitely right to have too many strips rather than too few. Getting the length right on a very 3d boat, on the other hand was a nightmare, but in any rational new build that wouldnt be an issue. 2mm ply was definitely much easier than 2.5mm veneer, having tried both, but if you use ply you cant varnish because the smart money is youll go through the outer layer in some (or in my case, many) places when fairing up.

I did the boat partly in 2 * 3mm and partly in 3 * 2mm. The junction between the two was something of a pain and in any case I carried 3mm too far forward. The last bit of 3mm was definitely excessively 3d. Im sure the boat is somewhat asymmettric in that area because with the panels at 45/45 ish, bending the last bit was problematic. The first layer has a much bigger impact on final shape than subsequent ones, and in the transition on one side the first skin was 2mm and the other 3mm. It would probably have been better to suffer the horrendous cost of the 2mm ply and done the whole boat in that. If I were doing a new boat it would be 2 * 2mm ply all over with a glass skin inside and out, uprating the inner skin appreciably in the slamming area round the bow by adding inner glass over skin and stringers, not under stringers.

This was the first project I used a router on which was interesting. Vision really was a major problem, I guess my shop isnt that well lit because I found it really hard to see what the cutting edge was doing. For a long accurate cut to put a rabett in the glass topside (ouch, terrible thing to do to a cutting tool) I stapled a batten as a guide right along the boat and that was a major win. The other thing that helped with a router was to get a marker pen and colour the area I wanted to remove, which made it soo much easier to be confident about what I was doing. I still had a few slips in the wrong places though. 

Some photos...

Looks like Jim was able to cold mold over two stringers per side as well as the topside stringer junction.








Finished hull. The Skol featured a self-draining hull. George A, fellow Classic Moth bloggist over at Mid-Atlantic Musings, has also deconstructed a Skol back to a bare hull. Click here to read about his Skol project.




Jim adds the history of the Skol in the comments section which Ive dragged to the main post.

"From what I can make out there seem to have been 4 Skol [models].

Mk 1 may have just been 3 prototypes, which look as if they had unstayed masts and a fair gunwale line.

George A.s boat is a Mk 2. The 1969 Moth yearbook said production was planned for two versions, a SL and regate version. The SL was to have a daggerboard and was the lighter built. The yearbook also says [it sported] an unstayed mast. I think in practice many were built with stayed rigs. They seem to have had false floors and stern tanks, at least some with drains through the stern tank. The actual production detail may have varied, but all had the little extra piece at max beam [hiking winglets].

Mine started life as a Skol Mk 3. She has a fair gunwale line, an open stern and a deck stepped mast. The shrouds were supported by glassed in alloy tubes down to the base of the mast foot.


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Selasa, 01 Maret 2016

Boatbuilding Lark Scow Part 1

Other posts on the Lark scow.


Peter Gilbert of the Erieau Lark fleet in Canada has started a new Lark scow (named Pinky Too, his Dad built Pinky 2 and Pinky 3) using the Kerr plans. He sends along some photos. The Kerr plans follow the original C.G. Davis plans in using a lot of frames. Instead of sawn frames, Peter has laminated the arc sections. He is planking the bottom of the Lark with plywood but with a hi-tech twist; he is using 3mm plywood with a carbon fiber sheathing (I wonder how this will square with the Erieau Y.C fleet as Peters construction may possibly result in a Lark considerably lighter than the current boats.)

I like how these builders determine fairness using a full glass of beer as a sight-line.




The solid timber side planks hold everything together before the bottom and deck goes on.











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Minggu, 28 Februari 2016

Boatbuilding A Piece of Furniture

"A piece of furniture" we would often say as we eyeballed those McCutcheon or Souter built Classic International 14 dinghies, cold-molded in mahogany, glowing with multi-coats of varnish, all joints carefully crafted, beautiful wood everywhere. I was reminded of superior dinghy craftsmanship when I came across this stunning photo of  the interior of the most recent addition to the historical Australian 18 foot skiff fleet, the reproduction Myra Too.




Myra Too was built in 2013 by Bob McLeod to reconstructed lines (by Australian National Maritime Museum curator, David Payne) of the 1951 championship winner. Myra Too was originally built and raced by Aussie legend, Billy Barnett. To build the reproduction hull, Bob McLeod used silver ash and, in the inner and outer layers of the hull, Queensland red cedar (the outer layers used rare, full-length pieces estimated to be between 400 to 600 years old).

Here is the original post on Myra Toos construction from the Australian National Maritime Museum blog.

From YouTube comes what, at first view, looks to be a typical mast-head GoPro video -- this of the historical 18 footer Yendys going around the course, However, with the historical 18 footers nothing is typical. Of interest to me was the spinnaker set starting at about 1:50 into the video. It takes four crew members to get the mammoth spinnaker pole out onto the mast, three of them heave-ho pushing and a fourth slotting the multi-piece pole together as it goes out. Once out, this long, long spinnaker pole then wags all over the place as they go downwind. These pre WWII 18s were heavy dinghies with lots of crew and this video shows that they pushed a lot of water around as they bashed around the race-course.

The history of Yendys from the Australian National Maritime Museum blog.
"A rival of Britannia, Yendys was built in 1925 by Charlie Hayes for Norm Blackman. This big hull is also built in the traditional heavy scantlings, but it illustrates an early piece of innovation, its transom bow. Hayes had another legend working for him at the time, Charlie Peel, who had been successful with transom bows on 14-foot skiffs in Victoria. As well, the 1920s was the time when the Restricted 21s showed how fast a lighter-keel boat could go, and Hayes and Peel were in the thick of this class too. Out comes Yendys, with its sawn-off profile and veed bow shapes, a sort of restricted-class yacht crossed with a skiff and with the bow overhang squared off. Despite the odd mix it went pretty well too, but although another two snub-nosers were built in that time, the idea did not catch on. It did show there was room to move in the rules, though, and the Queenslanders took on both innovation and the establishment at the same time."



And a post featuring a photo of a pretty deck on a 505.
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Jumat, 26 Februari 2016

Boatbuilding More Progress by John Z on his Classic Moth

Hull panel offsets for the Mistral can be found here.


In the ongoing coverage of John Zs Classic Moth build, last week I stopped over at his shop to gauge his progress and have a beer. The Classic Moth modified Mistral design is now upside down awaiting gunwhales and a layer of 4 oz. glass over the bottom.

This photo, though perhaps a tad distorted, shows how deeply Veed the Mistral design sections are around the midships.


Transom view with a pretty swirly pattern from the okoume plywood.


John, with the about-to-be-opened bottle of stout peeking up above the keel-line of his Moth.


A man and his workbench. John graciously took down a Marblehead RC sailboat he built many years ago so I could take a closer look.


A man and his workbench - take 2.


From the previous photo, you can see that John has some interesting stuff hanging from his walls. This is the box containing his F1 rubber-band indoor airplanes. These are extremely finicky to make, with a minimum weight of one gram. John has all the various tools to test balsa density and strength; tools to strip balsa into extremely narrow widths; tools to check rubber band elasticity; molds to make the tricky propellers, and the various techniques to apply the ultra-thin microfilm covering.  To make a F1 takes a methodical, painstaking craftsman.


John also has two half models of the Americas Cup, IACC keelboats, the class that precedes the current foiling catamarans. Surprisingly, it was through his wifes connections and not his Naval Architect circle of friends that these two half-models now grace his shop.





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Kamis, 18 Februari 2016

Boatbuilding Update on the Nantais Classic Moth

Plans de Moth Classique


David Simms of British Columbia, Canada, sends along an update on his build of the French Moth Classique Nantais design. My first post on Daves boatbuilding can be found here.

"Ive attached a couple of pictures of the Nantais, in its present state... All of the frames are made of laminated 1 cm x 1 cm, straight-grained Douglas Fir. Im amazed at how light, and STRONG, they are. Presently, the fairing has been nearly completed and the frames have been sealed with epoxy. There are fewer than a dozen screws in all of the deck framing. I have rough cut the plywood for the deck and Ive also sealed the inside face of the decking with epoxy. 
[Second picture] A bit of humour, here. Im struggling to move the boat into one of my sheds, for winter storage. This little struggle has convinced me that my original thoughts of building a boat that could be transported on top of a car were somewhat unrealistic. Given that Im not related to Charles Atlas, Ill soon be looking for a trailer."



Lines drawing of the Nantais Moth. Typical of Moth design for France and the U.S in the 1940s. (The Dorr-Willey, Ventnor, and the Abbots representing similar U.S. designs, Click here to view a post on the 1940 Moth designs.), the hull has a scow type stem married to deep V sections.



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Minggu, 14 Februari 2016

Boatbuilding in a Nation of Two Finger Texters and Page Swipers

One of the memes of modern American culture is we have lost our DIY aptitude (a characteristic particularly attached to the millennial generation). We dont fix our cars, we dont fix our houses, we dont build things..we pay someone else to do it. I was reminded of this when reading the geeky but very informative Professional Boatbuilder magazine (by the same publisher of Woodenboat magazine).. They did an article on Chesapeake Light Craft, the plywood boat-kit builders based here in Annapolis. Chesapeake Light Craft spends an inordinate amount of time trying to make their plans and kits so comprehensive there is very little room for error. I then read the following paragraph and my jaw dropped.
Some customers are so unskilled that it would be better not to sell them a plan or a kit. "So many people these days cant read plans at all. When a part is symmetrical around an axis and the plans only show half a part, some people build half the part. Thats happened twice in the last month. One guy made half of the deck and the bottom. We were very nice. I guess if you cant laugh, you have to cry...You cant make assumptions about anybody."[Professional Boatbuilder, Number 152, pg. 26]

Hmm! maybe we are becoming a nation of hopeless klutzes.

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Minggu, 07 Februari 2016

Edensaw Boatbuilding Competition A Sailing Dinghy Wins!

Most wooden boat shows have live boatbuilding; usually it involves a group of families assembling a quantity of small rowing skiffs which are then launched at the end of the weekend. At the Wooden Boat Festival hosted by the Northwest Maritime Center in Port Townshend, Washington, Edensaw Woods sponsors a boatbuilding competition where they move away from the typical novice boatbuilding event and open it up to a diverse group of boats from professional designers and being built by skilled woodworkers. In this years competition, built alongside the traditional dory and Irish curragh were two sailing dinghies. One of them, Richard Woods Zest singlehander, won the competition

Here are two of the boats on the beach after the time-limit for boatbuilding expired, ending all construction. On the left was a dory built only with hand tools. On the right is a 14 foot, V-sectioned sailing dinghy designed by sometime Classic Mothist, Stephen Ditmore. As the photo reveals, Ditmores team got the hull done over the weekend but the decking and rigging awaits.


Winner of the competition, designer Richard Woods on board at the initial push-off of his Zest dinghy. This is definitely a racing singlehander with hiking wings. (The hull is a relatively narrow, flat bottom shape.) The hull was completed by the team over the weekend and Richard was able to scavenge sailing parts from some of his other projects to get this design sailing in short order. I think the pushee in the photo is Michael Scott who owns several sailing dinghies including a couple of Classic International 14s and who is constantly feeding news tidbits to the blogmeister.


Instead of painting over the freshly applied epoxy, the Richard Woods team decided to apply a silver vinyl decal material over the hull (purchased at an auto supply store). Very distinctive, hence the boats name Silver Bullet.


Designer of the other sailing dinghy at the competition, Stephen Ditmore sailing his Classic Moth design. Unfortunately we have only seen his Moth show up once at Brigantine, New Jersey.


The wrap up video from the Edensaw competition.


Third Annual Edensaw Wooden Boat Building Challenge! from Al Bergstein on Vimeo.


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