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Wade Tarzia

Page history last edited by Wade Tarzia 10 years, 10 months ago

 

 

 

 

 

 

 

Photo #1, Bantam Lake, August 2008. 

 

 

 

Here is the tacking outrigger "Short Dragon" (a historical joke; one famous Viking longship was called "Long Dragon" -- yes it had a dragon-headed prow). The vaka (main hull) is 16 feet long, about 22 inches wide at the sheer, 14 inches wide at the very bottom, about 23 inches deep amidships, has about 3 inches of rocker, and sinks about 8 inches with me inside (with gear and rig). It is built of 1/4 inch A/C exterior plywood, glassed on the outside and on the inside from waterline down (including bottom). The bottom is finished with epoxy and graphite -- I was curious about its scratch resistance and desirability for mid-season touch-up. The ama-side of the canoe hull has dual leeboard-capture-rails; the leeboard can slide fore and aft about 40 inches from amidships (good for shunting proa CLR balance adjustments) but sailed as a tacking canoe, the leeboard is happy centered about a foot forward of amidships, which provides a little weatherhelm.  With all decks and seats mounted the vaka weighs about 150 pounds.

 

The 14 foot long V-bottom ama is 14 inches wide amidships, 14 inches deep amidships, is decked and sealed and foam-filled, and weighs about 70 pounds and displaces about 200 pounds of water with an inch of freeboard remaining. With the foam installed, the ama holds about 17 gallons of water (or about 140 pounds); therefore, if I decided to sail the canoe like a shunting proa, water ballast with reserve buoyancy is an option.  I added super-heavy fiberglass strips on the V-bottom (keel) where the v-keel will be digging into sand and pebbles.

 

The desirability for this kind of ama for a tacking boat can be questionable -- keep in mind that V-hulls tend to be the quick, cheap, and easy solution to making a hull, not the most elegant solution.  Fair enough.  Still, I have no complaints.  First designed for use in proa-mode, the ama seemed like a good enough idea, its V-bottom offering ease of construction and quiet re-entry into the water (no annoying slapping), its weight useful windward ballast, and its flotation volume just enough for safety (re-entering boat from the water, sail-aback flotation safety, possibly sinkable/floodable for righting proa and emptying vaka of some water after capsize).  I am pleased with its relative quietness. 

 

For a shunting proa, the V-ama is OK. However, a tacking outrigger or double outrigger works best with its ama volume forward, to resist the "diagonal" forces (and the dreadful diagonal capsize).  The plywood V-hull method makes  getting buoyancy volume forward difficult.  You can torture the plywood a little and get it somewhat forward, but not well forward. Your benefit is at least an easy entry and exit profile. 

 

And yet I have sailed in B3 winds and higher in gusts with the ama to leeward -- in this mode, the water shoots like a mist from the bow of the ama and the canoe can attain high speeds (regularly 7-8 mph on this tack, and up to 12 mph in gusts, GPS meaured); however, the front of the ama is pressed down far enough for me to be vary wary at the higher speeds.  Beating to windward in steep waves at about 5 to 6 mph has shown the ama is within safe limits, however. Its sharp bow penetrates the wave face at these speeds but the winde mid-sectioon brings the ama up swiftly. Also, the ama's deep-V form helps with stable tracking but does slows down turning (see below).  Also, it helps prevent leeway with my leeboard up in shallow water.   

 

Tacking:  the boat sometimes tacks well enough if I manage the choreography of the two sails and time the rudder turn perfefctly.  Otherwise, I get some help by  holding the main boom out to push bow over.  In heavier wind and steep waves, with the boat going faster, it has trouble going through stays unless I cast off the mizzen sheet. I had the mizzen sheet tied off on a horn cleat, good enough for long tacks, but sometimes difficult to release quickly while sailing is rough water,  when I am busy holding on and watching the water, etc.   In 3 foot waves in Long Island Sound, and a good breeze, and a pitching, rolling canoe, I could not tack at all one time until I headed up to the waves and gave full attention to untyoing the mizzen sheet so I could finally get COE forward and tack.

 

That learned me my lesson: I built a cam cleat for this sheet, attached to the edge of the cockpit seat, designed and angled for tight-holding, quick release, and quick re-setting.  That improved things a lot!  Now I can continually readjust the mizzen angle with no real bother, and sometimes get through stays. The key to using a small cheap cam cleat on 1/4 inch line is to increase the angle between line and cleat (so that the line tension pulls the line down into the cleat), and to build a little turning post in front of the cleat to take a turn with the slippery, thin line before it leads to the down-angled cam cleat.  The turning post must not interfere with your jerking the sheet free for readjustment -- no horns!  I ground a hollow around the dowel to help hold the turned line.  Or...you can buy an excellent, very expensive cam-cleat!

 

The akas are laminated from Douglas Fir flooring planks from lumber store (clear of knots and finish-planed; they came with a shallow, wide central groove which I have to plane flat). They are three planks toward the aka end and 4 planks toward the vaka end. At 30 pounds combined they are heavy, but I am comforted by the thought that the akas probably will not break. Since this is a tacking outrigger canoe, the akas do need to be stronger than those used for a shunting Pacific-mode proa (ama always kept to windward, never taking sail or hull loads).

 

The assembled boat is 7 feet wide, outer gunwale to outer gunwale. This width is required by my garage to keep the boat on the trailer fully assembled.  The stayless cat-ketch rig takes about 20 minutes to set up, ignition off to ready-to-launch. (When previously I trailered the boat unassembled, assembly took at least 45 minutes of vigorous work. I changed my trailer to carry the fully assembled canoe on two 7 foot cross beams bolted to the plywood top on the trailer bed; I am very happy with this set up even if I lose some total boat beam; a boat that is fast to set up and launch is used more often!).  

 

The sail rig is planned to be variable for experimentation. I have different mast step options. The first option is the cat-ketch rig, with a far-forward main step, and a mizzen step at the end of my cockpit.  I have another main step further back, for use with a single sail. I have a stub mast built to take an oceanic sprit sail or a bermudan sail -- I have not tried that set up yet. I also have a more central mast step if I have to drop the main in sustained gusts or if I want to push off into windy weather (for me defined as 20-25 mph) -- I would then move the mizzen mast to the 3rd step to use it as a heavy weather sail. I have never used the middle step. 

 

To clarify this situation, consider: mast step 1 is far-forward in the bow (about a foot back from the stem, like a cat boat mast), for the main-lug in ketch rig configuration. Step 2 is about 25 inches back from the stem, for a single sail configuration.  Step 3 a foot or so forward of amidships. Step 4 is the mizzen step, at the end of the cockpit in front of the aft aka.

 

I have sailed with the small mizzen in the mast step #1 when my girlfriend's grandaughter wanted to try sailing and I wanted a very sedate sail-area -- and the boat sailed well enough with the leeboard pushed all the way forward, and made some progress to windward.  Therefore I now think the more central mast step will not be needed for using the small sail as a main sail.

 

The ketch rig uses two standing lugs from The Wooden Boat store: a 54 sq foot main from the Shellback Dinghy and a 37 sq ft standing lug mizzen for their small Nutshell Pram.    I am now trying to learn to use this rig and improve some weak windward performance (55-60 degrees made good to windward). Having read a bunch of Wooden Boat Forum threads, I have not learned much! Some people claim I ought to be doing better, and others claim that 55 degrees is about as good as it will get for a low-aspect-ratio ketch without a jib.  The Herreshoff ketch-rigged Coquina evidently gets to windward similarly. 

 

No doubt I will learn more as time goes by and I better tune the rig  ( for one, I think my very bendy windsurfer masts are not helping me; for two, I must experiment with the halyard position on the yard arms; for three, I think I ought to built slightly thinner yard arms that flex more), but I have learned to live with this weak windward performance.  This is because the canoe is pretty fast for a 16 footer, so blazing along at a very close reach is not too bad as long as I am not dying of thirst or hypothermia trying to get home! 

 

GPS measurements so far say that my doldurms/light wind performance tends to be 3-5 mph.  I usually sail at 6-8 mph in any wind over 5 mph up to around 10 mph.  In any wind wind over 10 mph I frequently hit speeds of 8-12 mph.  My top speed so far has been 14 mph but this was a rarity and the canoe is rather scary at such a speed with the ama pressed down to its limit (these are all reaching and close-reaching speeds.  This canoe regularly breaks its hull-speed limitations, as most narrow sailing canoes do.  I am totally spoiled by these speeds, I must confess.  

 

The rudder is a doubtful experiment with an Indonesian side-rudder arrangement (reminds also of a Viking-era steering oar) set up about a foot behind the aft aka. It is attached to its bottom bearing with a low-stretch line (running up to the gunwale, into the boat, and onto horn cleat and cam-cleat.  Before I get into shallow water, I release the rudder line, and it tilts up onm its gunwale-level bearing (a simple lashing against a cross-post just behind the aft aka).  The rudder might not be large enough or aft enough to steer the canoe through the wind in a tack.  Probably a stern kick-up rudder with push/pull pole and yoke will be better. However, it does work, is very simple, and can be fixed easily.  The lashings bring flexibility into the system, which is good, but also bad -- the half-inch to an inch of play is annoying and cannot help rudder efficiency.  I am now roughing out a stern-mounted kick-up rudder to try that (8/18/09).

 

I finally added a side-seat on the ama side (6/2009) -- I had reached limits sailing the boat from the cockpit all the time.  The ama can easily fly in any wind over 7 mph.  The seat made ama-to-windward sailing much safer, as you would expect -- but the ride is very wet!  Spray from bow and leeboard attachments make the need for a spray dodger.  Sailing in in full waterproofs is best on that tack but on the hot days I let myself get wet.  In steady 5-6 mph winds I can still sail in the cockpit and keep the highly rockered ama about three inches in the water (close to flying it) to enhance speed in the light wind; in this mode, only about 3 to 5 feet of the V-keel touches water.  

 

In August of 2009 I did a capsize test on a calm lake. The hull is open but I have pink foam blocks under both thwards and in the stern area. There is probably about 150 pounds of flotation.  Caprizing the boat fully rigged and with the mizzen sheeted in and cleated, I rolled the canoe over. It floated at 90 degrees on its masts and spars.  I climed on the canoe hull and it sank under my weight until i was about waist deep in the flat water.  Then I simply pressed against the upright aka and brough the boat down again, filled with water like a bath tub.  I would never have been able to clear the hull in any kind of waves. About fifteen minutes of bailing and pumping on shore cleared it.  If I had been able to open a bailer port on the hull, the foam would have pulled the hull up in the water somewhat and cleared some of that amount.

 

Thus, the canoe is not safe for thre rough water on Long Island Sound where I typically sail in short steep waves. Even a few miles out in the deeper water, I occasionally encounter a set of hollow 4-foot waves which usually deposit a gallon of water into the boat over the bow.  So.... I want to seal in most of the hull by installing decks and bulkheads with water-tight hatches and ports for shore-side ventilation and gear stowage. I would leave myself a deep foot well for the aft seating position. The decking would be at the seat level, so that I would have ~6 inches of topsides left over for a reclining/sleeping platform. If I cover the aft foot well with a hinged cover (doubling as my cockpit seat when folded back), then I would have a full 6 foot sleep platform with a 6 inch lip to hold me in the boat.  I seldom have a passenger, but I could install a forward hatch to create a foot well for a passenger, as well as large gear access.  I do not have the amibition for this project right now (yes, I should have done it last winter!) but until I do, I will not be sailing the boat more than 4 or 5 miles from shore. 

 

I also contemplate the change to smaller, flatter mizzen sail and keeping the 37 sq foot lug for a heavy-weather mainsail (bundled up and carried ont he boat on its spars). Mizzen sails can be pretty flat due to the backwinding from the main sail, so perhaps this is a white-polytarp solution?  I have a small marconi sail I could cut down for the mizzen, but it would still have draft. 

 

Summary -- I am still very happy with this boat though I constantly moan that I didn't build a 20 or 24 footer (with the aft section folded up to fit the boat in the garage).

 

 

Comments (1)

dstgean@... said

at 12:46 pm on Mar 23, 2009

Wade,

Throw a page on wikiproa about your ideas in addition to proafile7. I'd love to see the 24' box actually get built!

Dan

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