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Finished the revamped 15.5 metre wing mast for Groucho. Could only obtain 4mm ply for the skin so took belt sander and reduced thickness by a mm or so ... to reduce weight by a ridiculous and minimal amount - but now know I can do no more so need to relax. Can still pick the mast up myself including all rigging - but it is an effort. Just helped Eric Eason drop and then later rehoist his tall 11 metre alloy mast for his breathed on Crowther 24 - and figure the two masts are close to same weight so as said, calm down.

yellowmast.jpg

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Frog has a D section mast with two sail tracks for the double luff main, actually two complete mains to make the full wing cross section. Not much use for you. However Frog's leading mast section is the same as my conventional single luff masts, see the two cross section plans. Third image is of a trimaran beam and this is built very much in the same manner as the masts ... but this beam has two central I beams to make a box; (for greater rigidity, but also more weight) my masts have only a single I beam. The frames are placed at 1 metre spacings and are cut out for halyards to run. Groucho's mast is 15.5 x 0.5 metres.

IMG_2030.JPG

grouchomast.jpg

sidbeam.jpg

putikibay.jpg

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  • 5 weeks later...

Holy, Moly ... congrats for Frog, GM. What an impressive mashine. I appreciate it you give us fellows an insight into your laboratory. You are one of these genius "Gyro Gearloose" who gives us sailors awesome boats to sail.

P.S.: If you don't mind, will send you a PM about Jim Young's 40 footer. 

 

 

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  • 3 weeks later...

Building in thin strip plank cedar (mostly) a 3.6m 2 piece rowing skiff to carry each side of the cabin on Groucho.  The central bulkheads are two thicknesses of thin ply reinforced with carbon with four bolts to lock bulkheads together .... and when skiff is completed, will saw them apart.

rowing skiff.jpg

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  • 1 month later...

The joint is there simply because of splicing lengths of ply together. The  mid and after sections are one piece bent over keelson and frames (to get a semi-circular cross section shape below waterline) while the forward areas are cut and spliced to keelson  to get a soft V shape (or sharp U). It is basic tortured ply method; a build process that is rarely used today - but one where you can get a very light and stiff hull form. I build initially upside down - but there are no rules. Check out the Gougeons' book for more details. Has to be thin ply though, 4.5 or 5mm is too stiff to shape into the correct curves.

frog cebtral and aft.jpg

Frog3copy.jpg

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  • 5 weeks later...

Wanting to lift the mast on Groucho but have to wait while a pair of dawn swallows finish raising their chicks ... nest situated in the after section of wing mast, hard up against the central I beam and just in from the mast spanner. Doesn't matter, have been sailing Frog and also cleaning the too healthy growth of oysters off the bottom of Cox's Bay Skimmer and repainting.

grouchosun.jpg

skimmerside copy - Copy.jpg

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  • 2 weeks later...

Under joist clearance not an issue? No termites? Attractive patio design, pretty house. Just wondering, not criticizing, we can't do that due to code and rot here. It's an attractive, older look, seen a lot in the NW US and NE where you can bring the siding right to grade.

Btw, fan of your projects.

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If I'm reading you correctly, Bruno, in NZ and Australia we have a tradition for large overhanging roofs, for shade and rain in both wet winter and hot summer climates - and in the classic mid 19th and first half of 20 Century southern antipodean house designs, often a verandah running around two or three sides of houses.  We don't get termites here. Get wetas though, like a nightmare looking and large sort-of elongated spider, harmless though. The tropical looking native parapara plants under our "verandah" have been pruned to waist height. Interestingly in steep hill country Wellington, which gets ferocious winds, people have plants/trees growing right up to overhanging roof undersides ... to reduce the sonic booms in gales.

ps: this is a weta, exposed when the nikau palm frond base fell off - but this is a young, small weta, large ones would fill and overlap your hand

wetanikau.jpg

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Light airs at first on Frog, then breeze shut off and than came back from east with some power; Frog took off - but too busy to take photographs. D mast with double luff main. Tiny floats; am used to them now but early sailing was apprehensive.

frog_rig.jpg

frog_light_airs.jpg

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Bill Barry designed and built it/them  - because they are two separate and identical mains which are not joined except at the two clew positions. The leeches  touch but have no attachments and are free to move depending on mast rotation.

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What I've seen on a D mast here in Perth is the clews are attached to each other with a rope that has a pulley between them connected to the outhaul so outhaul can be applied but the two sails can still slide past one another with mast rotation.

Is that what you have ?

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Supplementary question;

Are the two sails the same weight cloth and battens as you would construct for a single sail ?

The consequence of course is double the weight aloft, as they are separated they would have to be wouldn't they ?

Or is it say 70 or  80% ?

The D mast concept fascinates me, its two steps above the Tiki Wingsail but no where near the complexity of a solid, and reefable !

All you need now is a slot ! ;)

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The clew attachments on Frog are very basic, just a couple of lines around the thin section of the boom. There is enough slackness to allow enough push/pull movement between the two sails. Works okay. Could be more sophisticated, as on larger boats but Frog is small so I get away with it being simple. Each sail is of lighter material than a single setup but the two together weigh maybe 20% more, have to live with that. What you gain from the D mast and the two sails curving off from the tracks is a very smooth transition mast/sail, an aerodynamic wing shape, superior to normal wing mast, soft sail. A conventional wing mast rotated to the correct mast/sail position for sailing has a dead area aft of the mast on the windward sail side. Photograph doesn't really show this but it is there.

sid'smastsail.jpg

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Asking for a friend of course...

Let's say my friend is not a money bags.

But this friend definitely understands that a 3di sail is not actually 5x more expensive... Because the sails have better durability.

So, would this type of setup allow each main to last a little longer, perhaps due to less drag I.e. less stresses on the fabric? Or are we still talking 2x as expensive, even over time?

I'm fucking rich so I don't personally care of course.

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I haven't accurately weighed the double main, just guessed but having sailed today and then rolled them up, I believe the two of them including full length battens are only fractionally above the usual heavier cloth single main. maybe even lighter. Bill Barry did a nice job light building them and his pricing was very, very reasonable. Maybe because it was experimental and he knew he was dealing with someone crazy; this was a year before the AC75s with their very special sail rigs appeared.

 

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Lifted Groucho's mast  a couple of days ago, working carefully on my own using block and tackle high up in a pohutukawa tree; a natural gantry. (I back the boat under it at high tide) anyway the wing mast, now painted mostly light gray with a discrete yellow stripe, is 15.5 metres tall, over 50 odd feet.

Today a close to irate woman (with bright red dyed hair) shouted down at me from the high terrace above the bay then came down the steps threatening to lower the mast because it upset her elderly mother from the above terrace house. I pointed out the mast was nowhere near  as tall as a huge Northern hemisphere tree nearby on the same reserve, then discretely (for me) pointed out that boats have moored in Cox's for 200 years.

Maybe I should have stood back and let her lower the 75 kilo mast? I wonder how she would have achieved this.

PS: older photograph of Groucho (before it lifted mooring in a heavy gale and got smashed up ashore) in Cox's bay -  but you can see the terrace and the tall tree.

GrouchoCoxBay.jpg

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14 hours ago, Groucho Marx said:

Today a close to irate woman (with bright red dyed hair) shouted down at me from the high terrace above the bay then came down the steps threatening to lower the mast because it upset her elderly mother from the above terrace house. I pointed out the mast was nowhere near  as tall as a huge Northern hemisphere tree nearby on the same reserve, then discretely (for me) pointed out that boats have moored in Cox's for 200 years.

A missed opportunity to invite someone to go sailing on such a cool boat.

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Well, it's not quite ready, have to connect runners, fit the rudder and so on. Because the boat has inverted T rudder, have to swim it in from the case bottom.  But you are right, why didn't I think of that, offer the angry woman a harbour sail.

grouchomist2.jpg

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All quiet on western front, ..... so far.

Have completed fitting all the running rigging, new blocks and so on. Here's an early photograph of Sid's D mast with Eric Eason adding scale. The long spanner has been reduced because it blocked deck hatch entrance.

14361257_1422946311055868_1699306214748223660_o.jpg

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Nice work Groucho,

another sail question, are they cut dead flat ?

If not what sort of shaping do they have ?

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I wanted flat but sailmaker Bill Barry disagreed and played around with the top areas with a slight luff curve - but to me. looks dead flat. You can vary fullness/flatness by playing with mast spanner rotation. Well, that's what I tell myself.

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  • 1 month later...

Groucho's rig is quite tall at 15.5 metres (on a 11.3 m platform) but Frog's D mast (for the experimental double luff mains) is only 8.8m (on a 7.2 metre long hull) and in light airs Frog's performance is not nose bleeding stuff. And yesterday was beaten in light winds by a vintage Armstrong tri with decent roached main and new large jib/genoa - and crewed by two stroppy women. Which definitely got my attention. So enough of this una rig fixation I've had for many years, bite  bullet and order a flat light weather headsail from sailmaker Bill Barry. Having said that in winds above 6 knots Frog really comes alive ... but as mentioned not so impressive in the light stuff when sail power doesn't compensate for foil drag..

 

frog blackwhite.jpg

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  • 2 weeks later...

Couple of shots taken by Jacques at Motions Creek (no pun meant) a couple of days before the harbour (and most everything else here) was closed. The rig is way too small, almost embarrassing, hence the headsail talk.

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On 3/29/2020 at 4:00 PM, Groucho Marx said:

Frog and traditional gaff rigged 22 foot Mullet boat Melita at Motions Creek. Closer shot of Frog.

motions3.jpg

frgmotions5.jpg

FUCK YEAH FROG. 

FUCK YEAH!!!

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  • 1 month later...
15 hours ago, Jono said:

I was kind of hoping for the Sea Spray siren shot. Made quite an impression on a young lad back in the day.

Lost to the ages I'm afraid. That image on Supplejack was of Sue Patterson who was manager of Limbs Dance company in those days. Here she is again.

Sue Clinton.jpg

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  • 2 weeks later...

Groucho, patiently waiting (see photograph) while the lock down coronavirus period came to an end here, got smashed during recent blow, the paulownia, glass and carbon starboard beam broke in half ending up on top of the boat with the toppled mast (now in three pieces) half on top of that; a mess. I built the beam maybe 20 years ago choosing paulownia because of its no rot properties.  But peering at the broken area the material had rotted away to crumbly dark brown stuff leaving no substance between the laminates. So much for that theory.

Have dragged wreckage ashore and cut it up. Groucho now floats like a proa with the smashed beam cut off next to the main hull. Thought about why not make it a proa but then changed mind. So have drawn up a new beam, asymmetric in cross section. Make use of the lifting shape. Still deciding what material to use. Will keep me occupied over the winter. Also have drawn two versions of a smaller chord wing mast - but that can wait.  Will post drawings later. In meantime Frog is cleaned and ready to sail. Lucky I've got too many boats?

 

grouchobow.jpg

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Sorry to hear that Gary.

I like the "never say die" attitude,  &    as Buzz Lightyear would say.....             Onwards and upwards  !     :huh:

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My son used to have a Buzz Lightyear toy that said" to infinity and a blond" , he asked me about it one day and I told him that"Buzz must have met your mom."

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18 hours ago, Groucho Marx said:

Groucho now floats like a proa with the smashed beam cut off next to the main hull. Thought about why not make it a proa but then changed mind. 

Wise decision, old son.  It would only make it cheaper, faster, lighter, easier to build and more interesting to sail.  

Sorry to hear it broke, but better on the mooring than half way to Great Barrier.    Paulonia is a great strip plank material.  But if it didn't rot when it got wet and warm, we would be in deep doodoo.

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If I did a proa it would need a double ended main hull - so that rules out Groucho. A proa would be lighter but not faster than a foil design, easier to build, yes, but not so sure about the more interesting design to sail ... maybe equal?

About the rotten paulownia: the strip planked beam was glassed both sides, double and triple in some areas with many bands diagonally and right angles of uni-carbon wrapped around beam. But there were areas, especially where it broke but also at float connections where rot had eaten all the wood substance away. And i thought the Chinese built coffins that lasted for a Century or more?

Anyway, am considering a box beam in ply and carbon for the replacement. But could change mind tomorrow?  Here is Sid's beam before skinning.

15A_0165.jpg

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  • 4 weeks later...

Mr. Groucho Marx, I think I am the voice of the majority here, when I tell you:

We need to see videos of your boats sailing! ANd I do not mean a 30 seconds tit bit here! But minutes long videos where we can all appreciate (and envy) what you have done!

If there is a youtube channel somewhere, please post it!

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I didn't get my head around Gopros; (am an old classic still photographer from way back) didn't like the extreme wide angle distortion and didn't persevere with achieving longer videos using less memory - so the little camera sits in a box.  What I have are all around 30/60 plus megs - and maximum here is 9 something - so the very short piece I've posted here will just annoy.

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49 minutes ago, Groucho Marx said:

so the very short piece I've posted here will just annoy.

DAMMIT this does annoy because it looks extraordinary! P.S. Post them to YouTube. You got this, I believe in you (I completely understand where you are coming from, I'm also a traditional still photographer). 

Can I start the question train? What is the TWS and BS in that video? Looks like a rocket ship moving in 2kts of "wind"... 

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2 hours ago, Groucho Marx said:

I didn't get my head around Gopros; (am an old classic still photographer from way back) didn't like the extreme wide angle distortion and didn't persevere with achieving longer videos using less memory - so the little camera sits in a box.  What I have are all around 30/60 plus megs - and maximum here is 9 something - so the very short piece I've posted here will just annoy.

You managed to make me happy and frustrated at the same time;  well done !! ;)

 

Floating Duck is right, Youtube is your friend.... We believe in you...

 

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7 hours ago, Laurent said:

Mr. Groucho Marx, I think I am the voice of the majority here, when I tell you:

We need to see videos of your boats sailing! ANd I do not mean a 30 seconds tit bit here! But minutes long videos where we can all appreciate (and envy) what you have done!

If there is a youtube channel somewhere, please post it!

He makes up for it with his still photography.

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That was on the late Sid Vicious, which lived up to its name; wind was maybe 4-5 knots and we're moving in excess of that. Speed was effortless on Sid. Should replace that foiler (with lesser chord wing mast) but am too busy building new box beam for Groucho. Also I'm getting too old for this sort of craziness. My 94 year old friend and famous NZ designer Jim Young died a couple of nights ago. Sobers a bloke up. Talked on phone to him for probably a couple of hours the morning before; didn't realize that would be last communication.

 

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  • 4 weeks later...

Getting the new main beam box section fitted to Groucho's main hull has taken some time, hence lack of news. Beam is in 4.5mm ply and although it looks large at moment in box shape form, once the forward and after wing shaped sections are attached will shrink visually. The box beam in cross section is slightly less in depth than the original strip planked paulownia so I've mounted it a little higher in main hull - which radically increases crawling below the structure comfort. Compared to cramped Frog, Groucho is pure luxury. Tongue in cheek. Here is a two beam version of Sid with full length floats, named 3 Devils. Just playing around with lines drawings. Not serious.

Copy of New model 3Devils_Linesplan.bmp

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  • 2 weeks later...

11.3m overall length x 12.4 m overall beam, counting outfacing foils. To get platform to fit in restricted area had to let the after main hull overhang the wall. Hence the weight on bow because the platform is near tipping backwards into sea. Will skid it aft when there is next large tide.

grouchonewbeam2.jpg

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I have a somewhat smaller (6.5m), less beamy (now about 2.8m, planning on maybe 3 or 3.2m) tri for which I am about to start building floats (5.2m). I have thought about adding foils, either as you have, angled conventional, or vertical in case A class style. What would you recommend now? Bare boat is about 80 kg. rigged.

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It is a French 12 metre design from an owner/builder (will find out his name and post later) who sold it to David Armstrong who lives on waters edge of Cox's Bay. He (designer) is building a slightly smaller version for himself. The wing mast is also his design.

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9 hours ago, Bruno said:

I have a somewhat smaller (6.5m), less beamy (now about 2.8m, planning on maybe 3 or 3.2m) tri for which I am about to start building floats (5.2m). I have thought about adding foils, either as you have, angled conventional, or vertical in case A class style. What would you recommend now? Bare boat is about 80 kg. rigged.

Frog originally was 6.5 metre now lengthened to about 7.2 or so. Just imo, you need overall platform width approaching square on a trimaran foiler.  However out facing foils lets you reduce the overall platform width so that beam counting the foils also approaches square. Saves weight and reduces beam flexing. On one of my old tri foilers had angled in 45 degree foils that could be lifted like normal conventional daggers. Photograph is of David Knaggs designed foiler with foils that swiveled up. There are many alternatives and there are no rules.

knaggs foiler2 copy.jpg

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Some more information on the ahead-of-its-time Knaggs' foiler:

Knaggs turned to the trimaran/aeroplane configuration for his new design – a boat he drew in 1986: 18 feet long and including the angled inverted T foils set outboard of the floats, 30 feet wide ( 5.5 x 9 metres) – an elegant, low and wide craft. He built a wing mast that bent sideways when rotated to flatten the mainsail as speed increased."Deep camber was required for power at low speeds as no headsail was carried, but once flying the main had to be flattened. Adjustments needed to be automatic so the new foils were combined with a sensor (in appearance two foils per side) mounted outboard on a neatly designed mechanism that actuated a shaft set inside the strut – this altered a small flap on the foil trailing edge and this provided more or less lift and kept the boat flying at a regular angle. Knaggs warned: “You must keep everything simple. If you’re not careful you can find yourself going berserk with complex answers that just load the boat down with junk. But find yourself going   berserk with complex answers that just load the boat down with junk. But this was a revelation. Now I could scream down the face of a wave without worrying about the foils washing out or the boat burying.”

knaggsfoiler3copy.jpg

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  • 1 month later...

Slow process getting Groucho ready but now close to finishing the platform. Have just finished the chain plate carbon lamination for the stays and have only to add the airfoil fairing sections to the box beam. Going to repaint boat black, yellow under the wing beam, grey on top, see Skimmer image. Very conservative?  Should be launched off the terrace with next months 3.6 metre tides. About time! Incidentally, in heavy onshore winds a couple of months ago, big tides moved Groucho sideways by seas washing over the terrace which damaged the starboard float by bashing it down on concrete, all since repaired.

skimmer_smallchortmasts.jpg

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  • 4 weeks later...

Thanks for the post.  You inspired me to build a 3mm stressed ply paddle board.   And now a hollow hull surf board[also stressed ply].  It is a brave new occume world out there.  Bend and Go Boat-works.  Thank God for Crazy Glue and Accelerator.

 

 

 

 

 

 

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  • 3 months later...

Wing mast is ready to paint. Chord is a little less than the original at 450mm. Old wing mast was 520mm. A bit too greedy?  Conservatism rules. But new mast is lighter too. And has more carbon because the outer skin is only 2mm. Central web is also thicker than original at 4.5mm.

About time. Groucho is on mooring waiting. Looks okay in black/yellow livery. Like a wasp.

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  • 3 months later...

Groucho ready for mast lift but unfortunately I have to wait for an ugly bilge keeler that has got stuck under my pohutukawa gantry; tides will increase end of next week.

757U0018.JPG

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