Foiling Trailer sailer

stunningly effective ; endplates usually  more than double effective aspect ratio which would be approximately 4 therefore typical 75% of wind tunnel CoL which is attributed to a nominal infinite span but really is adequately endplated like your foil was. What foil  of Bora's did you compare it to?



Doubling the main foil effective area (due to endplates) and adding in 10% contribution from the forward rudder gives you a main foil Col of ~ 0.7. 

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I dug out some old photos of the canard moth 2012 

also put the boat sched in operating order with boats down sails rigged for moths and windsurfers .




Meanwhile back at the workshop fairing and flow coating of foils goes on as well as main hatch. I have also vacuum bag the carbon reinforcement over the knee on the leeboards. This consisted of1200 gm uni and 400 gm biaxial over the mid part with an extra 1200 uni at the forward edge for 50 mm  of the foil . The knee had 4 layers of uni 400 gm over most of it with an extra 3 layers ie 1200 gm over the lateral eye  all plus 400 gm  biaxial . My phone has not updated the photo yet but just looks black with a wrinkle in the corner of the knee bugger !  More fairing to look pretty,

Glued all the stanchion glass rods into the deck with reinforcement doublers 50 to 100 mm below deck . This means we can  wet sand the deck oh joy!!!  I think I will put her on wheels and push her outside for that pleasure 

t foils for the rudders have their foam glued in so are waiting for flat sanding then glueing together . Given the problems others have had  I will wrap them in 100 gm biaxial carbon but I need to make stainless steel T ‘S and glue them in at the same time . I  now have my welder back from my son so another weekend job plus fixing up the trailer.






My green approach to going to work is a modified cat trike road with fairing and electric assist  12 km one way in 17 mins give or take a minute. 8 watt hrs per km approx quite a bit less juice than a Tesla needs .


Meanwhile I collected the stainless steel “T” s to allow interchangeable mainfoils and 2 x5/8 ss rods as pivots from John at Arcright .
wrt fairing one of the advantages of straight foils is that you can make up fairly accurate 4.5 inch wide sanding blocks cutting the airfoil profile out of styrofoam blocks with a bandsaw.


Work slowly progresses fairing up the leeboard verticals . I cut out the actuator pivot and was quite happy with the carbon consolidation around the tube . Should easily be strong enough I hope !,
I also put the boat up on wheels partly for sanding and painting outside but also because we were put on evacuation alert for flooding so I wanted to be able to move Owl out and anchor her if I had to. Fortunately the weather passed with no flooding just a high and rising lake tide ! Boathouse is now on an isthmus .




Thinking about reshaping foils when I found the photos of the canard moth I pulled a few really old pics. I remembered creating airfoil dagger boards and rudders for a variety of boats back in the 1970s .Later in 1981when I bought my first keelboat nee original sport boat Salty Dog an illingworth and primrose JOG keeler built by John Durlou in1969. I reshaped the keel getting rid of the fusiform cross section and trying to get a NACA section approx irately .I also did the same to the rudder smoothed out the bustle and got rid of the flat on the stem.Biggest complement was you couldn’t tell that I had done any thing !
Next Keebler 1983 was a Spencer Saraband not a Simitar unfortunately which had a similar fusiform section keel .This had to be reshaped as she had no groove to windward . So in similar fashion wood 1/2 round leading edge klegecell foam fairing and glass over with a steel strap and plywood plus foam to fill in the trailing edge hollow .Then to crib from Ben Lexcen I endplated the keel with 2 small Horner tips in wood. Made a huge difference in upwind ability both angle and groove but surprisingly we picked up nearly .2 of a knot motoring . A couple of years later I could not help my self and had to make a flying rudder 0012 section with a composite 63 mm ss tube stock shed 80 with a solid insert welded in for 450 mm .surprisingly light . I had a good discussion with John Spencer about that which he approved of and was recommending as a update to his older designs.
Next up was multihulls and lots of foil games .







Slightly slow progress toe rails all glued on. primary fairing coat of epoxy bog applied with the help of the boat elf pictured who promises more sanding. Meanwhile bogging and fairing proceeds on the foil plug the leeboard uprights and the rudders . Finally warm enough to wind foil ,sail the moth and foil the f18 HT not a bad life really!!! Mast is in build with Forte and I am having discussions with Norths re the sails however launch is looking like next year .



Sorry not much to report just the dreaded sanding and bogging . The problem is the weather has become beautiful with so many sailing temptations .A couple of good blasts on the F18 HT in skimming mode on z foils two strings balancing on the head of a pin in 32 degrees .plus a couple of windsurf foiling short sessions starboard race foils like the IQ. But on the earlier carbon 147 litre board . I will pop up a couple of photos tomorrow
The hull is sanding up quite well because it is mostly planar still needs more touch up fairing /bogging . Leeboards are progressing as is the main hatch nearly finished . The plug for the horizontal foil is faired needs waxing and pval prior to vacuuming on the mould lower surface .
I have also been working on the prod or bow sprit 2.2 m long 1.6 m extension retractable into an banana shaped rectangular covered trench in the fore deck. I am building it out of 6 mm okuome because I do not have any 3mm only 4 mm hydroteck which weighs virtually the same and splinters. It will get a carbon uni wrap and biaxial as well which will be overkill . Photos when the bench is tidier !!!




Oh how I hate fairing slow progress but dragged her out today to cure off the bog at 32 degrees C . More sanding tomorrow interspersed with windfoiling or moth sailing . I aim to get paint on her before the end of my holiday in 2 1/2 weeks . However I have to go down to Spokane to pickup the mast that Forte has been building for me . Shpping 32 ft across the states is not cheap,hopefully it will arrive intact !



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