Return To Messing About In Boats' First Page
May 1, 2000 Issue
May 15, 2000 Issue
May 1, 2000
MORE NEW BOATS
Sportdory
By Jim Michalak
Sportdory is an attempt to improve upon a dory I built about 15 years ago. This one is slightly smaller than the usual, at 15' length and 4' beam and about 70 lbs. empty. I tried to reduce the big sweeping sheer of the traditional dory in hopes of reducing windbag and making the boat easier to cartop, recalling lashing my old one inverted to the cartop and having its bow and stem droop way down over hood and trunk. But I kept the little tombstone transom, having found it very important in stabilizing an inverted hull as I lifted the bow to the cartop rack.
Sportdory's structure is extremely spare. There are no frames or bulkheads of any sort, just wide open inside from stem to stem. Seating is done on a ditty box/seat which can be located anywhere. I've found this to work very well, the trick to keeping the boat stiff being a rigid wale structure around the open perimeter. There are two cross braces, similar to what you might see on a canoe, to hold the shape. The aft brace is also very important as a backrest for the passenger. Below that is all taped seam 1/4" plywood, three sheets required.
These boats are built without ladder frames or elaborate jigs. The sides and bottom are cut to prefab shapes and wrapped around some temporary forms. The seams are locked with temporary twisted wire loops and the rigid wale structure is added. At that point the hull has assumed its final shape and the forms can be discarded and the seams taped with fiberglass set in epoxy. If the temporary forms are removed prior to completion of the wale structure the hull will take on a different shape, most likely the ends will droop. So keeping those temporary forms in until then is important.
The center cross section of Sportdory and her bottom are about the same as my old dory. These boats are famous for being seaworthy but they take some getting used to. You can't stand up in one safely because the waterline beam is merely 2' wide and that no doubt is what gives the good speed. John Bell of Kennesaw, Georgia, who built the prototype shown in the photo, reported averaging 4.3 mph over a 1.3 mile stretch with medium effort. I think that is pretty typical. In good weather and with a bit of training you can av-erage 4 mph for several hours. The top beam at the oar locks flares to a full 4'. As a result these are very hard to tip over if you stay seated. They will roll deeply and frighten you and snap back upright. I never had water come on board my old one.
Sportdory will have good flow lines as long as the total weight is below 400 lbs. The hull with its gear will weigh about 100 lbs. Sportdory plans are $20. Jim Michalak, If 8 E. Randall, Lebanon, IL 62254, www.apci.net./-michalak
AF2
By Jim Michalak
The AF2 is the ancestor of both the AF3 sailboat and the AF4 powerboat that have appeared in previous "More New Boats" articles. They all have simple sharpie construction with cuddy cabins. The prototype AF2 was built by Richard Spelling of Sand Springs, Oklahoma AF2 is 20' long by 5.5' beam and maybe 600 lbs. empty. That makes her 5' longer and 6" wider and about twice the empty weight of the AF3. The result is a boat that is a bit more of a cruiser than a daysailer, with more headroom in the cabin. I should mention that you can't keep adding headroom to a cuddy cabin without getting badly bit after a while. Every time you raise the cabin roof you need to raise the cockpit seats so the skipper can see ahead. Most of us can see over a 3' high cabin if we sit just above the floor. So if you can sit up in your cabin, as you can with AF2, you can steer from the cockpit sitting on a low seat. If you raise the roof to say 4' cabin depth, the skipper will need to sit at least V above the cockpit floor.
On a small boat the crew's weight is so significant to the total that elevating the crew weight can require adding ballast down low to compensate. Total boat weight suddenly goes up. Adding much more cabin depth to AF2 will probably increase the 600 lbs. empty weight to 800 lbs. or 1000 lbs. in a quantum jump. And you'd get a totally different boat.
As it is, AF2 has no ballast other than a thick bottom. First hand experience backs up paper studies that show a boat like this will reach a maximum righting moment with little heel, say 15 or 20 degrees. That's often when the windward chine is just out of the water and the boat presents something of a V bottom to the waves just as the hull reaches its maximum sail carrying ability. Beyond that and it can carry less and less sail force until maybe 50 degrees of heel when it will capsize.
AF2 hasn't been capsized but the smaller AF3 has been capsized once in a test and another time at anchor (with a crewman climbing the mast). AF3 lies high on its side and AF2 should do the same having the same watertight cabin and large buoyancy/storage box in the stem. AF3 pops upright quickly with the weight of the skipper on the leeboard. I hope AF2 will do the same but eventually a boat can get so large that the weight of the skipper alone isn't enough to right the boat. I'm pretty sure boats like the Lightening and Flying Scott which are about the size of the AF2 will not be righted that way. AF2, with its higher buoyant cabin might make it up. And once a boat is righted you may not be able to climb back on board without a step or ladder or rope to help.
AF2's rig is a 114 SF gaff. I used the gaff to keep the mast short and easy to step. There are more lines to rig than with the traditional sharpie sprit but this sail sits well in lazyjacks and reefs nicely. In the photo Richard is testing a polytarp sail which has 3D shaping provided by a radial dart at the tack and another at the throat. We think he overdid the dart at the throat and he has reshaped it. This sail is held together with glass reinforced carpet tape but everyone who has tried taping polytarp says it is temporary, eventually you will have to sew it together. And I'm wondering out loud if a boat like AF2 is too heavy for a successful simple polytarp, sail. I'm sure they work well for boats up to a total weight of maybe 500 lbs. The loaded AF2 is probably twice that. Richard has his eye on a sail of real sailcloth but promises to test the polytarp sail to destruc-tion.
If you look at the photo you might make out the top of the pivoting leeboard on the hull side. There is only one leeboard, braced to take loads in either direction (so it's not really a "lee" board). It stays down from tack to tack and you handle it as if it were a centerboard, in fact it really is just a centerboard mounted outside the hull. Using a leeboard like this leaves all the room in the boat to the crew.
You might also make out another roomy feature in that the cabin top has a slotted walk-way down its entire center, an idea adapted from the Bolger Birdwatcher. The mast is mounted to one side of the slot and is not on centerline. So the crew can walk down that slotted top, right past the mast and up to the bow without going on deck or climbing over or under anything. He can stand beside the mast secure in the cabin while hoisting the sail. And yet the cabin roof side decks are wide enough to prevent swamping in a capsize (so I hope, it is true of the AF3). So the slot top is a very nice invention. I think its only downside comes when closing the top for camping. Anyone who has had a slot top boat prefers a simple snap-on tarp to keep the rain out but that doesn't marry well with having the mast poke out through the tarp. I think it can be done with sufficient drip coamings and a Velcro closure at the mast. AF2 uses simple nail and glue construc-tion. The plywood bill looks like six sheets of 1/4", seven sheets of 3/8", and one sheet of 1/2". Plans for AF2 are $35.
Jim Michalak, If 8 E. Randall, Lebanon, IL 62254, www.apci.net./-michalak
The Skiff Mayo
By Joseph W. Spaulding
In 1994, the Samuel Clyde went off to the WoodenBoat Show in Southwest Harbor, Maine. I had been assured by my operative in Maine that I would be able to borrow a skiff or dinghy suitable for going ashore at Baker's Island or rowing around Northeast Harbor to look at boats. However, when we got there, we were not able to borrow or rent a suitable skiff.
My friend Mayo was so bummed out that he groused about no dinghy for all 10 days of the trip. I vowed to build a 2nd 10-1/2' skiff from Dynamite Payson's Instant Boat Book. I messed up the first boat on the length of the top of the seat bulkhead so that the boat came out with more flare and more rocker than designed. However, it worked out fine and I left it in Stonington, CT for my son to use.
The new 10-1/2' skiff was built in a few weeks and I painted it a nice blue with beige interior. It was named Mayo and had a nice set of 7' Nova Scotia spruce oars which were secured at the WoodenBoat Show in Mystic.
I find that the oak wear strips on the bot-tom are super and they take all the grief from hauling the boat up on the beach or onto a dock. The boat rows well with the 7' oars. It has a bit of trouble tracking, but if you pay attention, it is just fine. I have rowed it to the band concert about a mile away in 1/2 hour with no discomfort. It also tows up to 12 mph behind the Samuel Clyde with good grace.
It has a few other virtues that are not too apparent and have not been given praise by either Phil Bolger or Dynamite Payson. First, is the lack of skeg. Most dinghies have some type of skeg to make them track well and I guess the eye sort of expects a skeg. Well, when launching with no skeg, the boat pushes back into the water with no hang-up on skids, rollers, or stones. I do not understand why the skegs are always placed plumb at the back. If they were sloped at about 30 degree slope, they would not hang up and would still give good tracking. Comments please.
The other feature is evident when you get it up on a dock or float. You can turn it up on its side and it will stay there so that you can walk around to the other side to lay it down, bottom up, or you can wash it out with a hose or sponge as chines and rails are external. You can also walk it around on its side and get it right where you want it when you lay it down. These are very important considerations when you are past the brute force stage of life and must use some ingenuity when "messing about in boats".
When the oak rub strips are wet, the boat comes up on the dock with great ease. A large person (250 lbs. plus) can stand at the side and the boat doesn't take on water. With its double 1/4" plywood bottom, the Mayo will last a long time. Any area where the plywood starts to show signs of abuse can be given an epoxy and glass armor.
I encourage anyone to build one of these wonderful skiffs. They are no work of art, but a wonderful and functional skiff, sort of like the VW Beetle of the 60s.
May 15, 2000
I Suggest My DD-18 For the Island Trail?
By Dennis Davis
Ben Fuller's piece "In Search of the Ideal Island Trail Cruiser" in the March 15th issue prompts me to suggest my DD18. This is a very easily driven little boat with ample space aboard for camping and a good turn of speed even when fitted with the two small lugsails and, of course, plenty of buoyancy. Stability is excellent and I think with a conventionally sited daggerboard she will go well to windward and be ideally suited to the Island Trail.
This one should appeal to those who want to build a simple boat for camp cruising. The 15'0" DD18 is essentially a hard chine plywood sailing canoe, but the big difference is that the aft positioned dagger board and twin sails allow ample flat floor space for two adults to sleep under a tent hung from the two masts. Construction is straightforward stitch & tape using four and half 8' x 4' sheets of 4 mm thick plywood.
The prototype DD 18 in the photos was built by Hugh Webb, a hobby boatbuilder. The sails and paddles/oars can be supplemented if required with a little extra power in the form of an outboard motor, so a well can be incorporated aft of the mizzen mast thwart. For rowing one or two removable thwarts can be fit-ted. On her maiden sail in 173-4 winds the DD 18 proved herself very amenable to being steered with the twin balanced lug sails. In less ideal conditions a conventional rudder controlled by an endless line should nicely overcome the difficulty of positioning the tiller, although builders may have their own ideas on this. However, the prototype does not go well to windward with the aft DB and equal area sails. A larger mizzen (schooner main) might improve things, so builders may prefer a more conventional position for the board. This will not interfere unduly with the deck space available for sleeping.
The DD 18 will carry two adults and two or three youngsters with room to spare for gear. Buoyancy is incorporated under the floor and at both ends. The finished weight of the boat will largely depend upon the materials used but should be within the capacity of two adults to carry and launch, as is the case with the prototype.
LOA 15'0" LWL 12'0" Beam 4'6" Draft 7" & 24" Sail Area 68 sf in the form of two identical fully battened balanced lug sails.
Plans and building instructions are $44 US including second class airmail. Please make checks payable to: Dennis Davis, and send to: 9 Great Burrow Rise, Northam, Bideford, Devon EX39 ITB, England.
Top Of Page
Return To Messing About In Boats' First Page
