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Willie, you had ride yet? I want to know how the new boat holds up to some serious stress. Nothing negative here, just know you are very aggressive when you sail. Not that your brother doesn't sail hard but he is a bit wormy in stature. Not that that's a bad thing. Sail on.

 

Dave wanted me to have a go on Saturday, but I had to finish the trailer so I can get the boat out of the parents' house. Right now I'm taking up too much of Dad & Dave's space and time.

 

Have lost a bit of weight, but it's true that I am an extremely aggressive sailor, and do still consider myself sort of the canoe class' version of the human stress test. However Dad is actually heavier than I am. And while he's not the walking version of Murphy's Law (anything that Willy can break he will break) that I sometimes, much to my chagrin, resemble, a seat and carriage that can handle him can handle me.

 

Will hopefully get to take Machete for a ride next weekend in Gloucester. If not then then definitely in Wickford two weekends from now.

 

Best,

Willy

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Hilarious commentary Dave.

+1

 

That thing looks like it slices through the water effortlessly!

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Need to audition for the next instalment in the "Anchorman - Legend of Ron Burgundy" series.....

 

Maybe just grow an awesome Magnum PI 'Tache to seal the deal (a whole hipster beard has too much windage drag).

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LOVE IT! Almost bought 189 before 204 was available, small world idnt.

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New video of Machete in some breeze!

 

https://www.youtube.com/watch?v=RtY4tJL36lw

What's everybody else cooking up? I haven't seen a single image of the Morrison 3 yet. Can somebody investigate? I'm quite curious.

 

DRC

M3 is still on the drawing board Dave. Just doing testing before finalising and going to a mould. Idea is to morph the ideas from the US and UK boats into one for light wind and heavy wind performance. M3 is M2 with more slender bow and BMS taken right back.

 

Steve C12 Performance Boats

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New video of Machete in some breeze!

What's everybody else cooking up? I haven't seen a single image of the Morrison 3 yet. Can somebody investigate? I'm quite curious.DRC
M3 is still on the drawing board Dave. Just doing testing before finalising and going to a mould. Idea is to morph the ideas from the US and UK boats into one for light wind and heavy wind performance. M3 is M2 with more slender bow and BMS taken right back.Steve C12 Performance Boats

Looks swift to me! Thanks for sharing, Steve.

DRC

 

New video of Machete in some breeze!

What's everybody else cooking up? I haven't seen a single image of the Morrison 3 yet. Can somebody investigate? I'm quite curious.DRC
M3 is still on the drawing board Dave. Just doing testing before finalising and going to a mould. Idea is to morph the ideas from the US and UK boats into one for light wind and heavy wind performance. M3 is M2 with more slender bow and BMS taken right back.Steve C12 Performance Boats

Looks swift to me! Thanks for sharing, Steve.

DRC

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Excellent Canoe racing this weekend in Wickford.

 

Saturday - good sailing, though not quite as much good racing. Fleet was still a little disorganized at our first home game of the season.

Sunday- Absolutely fabulous day. Once the sea breeze filled in conditions were ideal. Racing was tight, fast, and fun.

 

Dave and I ended up tied on points. He won the tie break.

 

Thank you Wickford Regatta. We'll be back next season.

 

Willy

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Hi everyone,

So after making through 22 of the 34 pages in this thread, I think boats are awesome and I really want one. Having said that, I am definitely a sailor/engineer/tinkerer and I want to design and build one. I have started doing some initial load calcs and these boats have some really highly loaded bits in them! So now I am REALLY interested but I wanted to gut check some things. Regarding rigging sizes, what type/size of shrouds and headstays are people running? For the folks who have more boat design experience here, does anyone have a feel or estimate for what the shrouds loads are?

 

And lastly, is there anyone in the Seattle-Tacoma-ish area who would want to get an out-of-shape/out-of-practice cat sailor a conversion experience?

 

Thanks,

Graham

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Shrouds are typically some version of 3mm or 1/8" cable. Die form is nice. If you can get it.

So 1500 qlbs ain't wrong by much.

SHC

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And lastly, is there anyone in the Seattle-Tacoma-ish area who would want to get an out-of-shape/out-of-practice cat sailor a conversion experience?

 

Thanks,

Graham

Sea-Tac area actually has a decent concentration of canoe sailors. Hit up Eric Taylor, the sailmaker in Port Angeles. Good guy with a good boat and makes a solid IC sail. Also Chris Maas and Todd Twigg are right up in the San Juans. Further up in Vancouver there's a couple more smart enthusiastic fellas, Bob Lewis and Breck Wagner. Generally a great group of guys, the lot of them. Contact any of the above and you'll be in good hands.

 

DRC

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Europa Cup on now, and there's live tracking of the races on the event website. Quite fascinating looking at individual speeds and stuff. All the bits are linked from here. http://www.intcanoe.org/en/2015europa.php

 

Gareth Caldwell won races 1 & 2, the first after trailing Robin Wood for most of the race, the second from early on. Race 3 about to start. The SAP standard icons are quite amusing, being very un Canoe shaped. Also quite amusing is the unlikely evolutions the boats apparently go through during less successful tacks!

Seems to be a fair bit of attrition, they're on their third race of the day and there are rather fewer starters than there were for race 1. I think its been pretty breezy and gusty and shifty too judging by the data.

 

I'm pretty sure Gareth is sailing his new Maas design boat.

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Live coverage of the ICs is promised today.

 

 

IC Races scheduled to start about 12:00 GMT

 

As of Weds evening Gareth Caldwell has two wins and leads overall, Robin Wood three wins and 2nd, and Chris Hampe two wins and is in 3rd place.

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The IC Coverage starts about 2:20:00 on the video.

 

Robin got two wins, to go well ahead in the series. I think 7th or better gets him the gold, but he could also finish out of the medals.

Gareth Caldwell is I think guaranteed silver.

Bronze is wide open

Chris Hampe had a day to forget.

 

Go to 3:15:30 to watch as comprehensive a port end start as you could ever hope to see.

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The IC Coverage starts about 2:20:00 on the video.

 

Robin got two wins, to go well ahead in the series. I think 7th or better gets him the gold, but he could also finish out of the medals.

Gareth Caldwell is I think guaranteed silver.

Bronze is wide open

Chris Hampe had a day to forget.

 

Go to 3:15:30 to watch as comprehensive a port end start as you could ever hope to see.

^also there's an excellent pin start at 2:49:02

The subsequent minute of Gareth footing out to the left is pretty great entertainment too.

DRC

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With the help of ace photographer Luka Bartulovic, we managed to shoot a canoe "How to" video during training hours at the Sugar Island encampment. Yuck it up.

DRC


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IT WORKS AWESOME! Can share some pix if you want, might be a tad diff without sliding seat in your case, but I love it.

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IC Nationals results -

 

Challenging conditions at Sail Newport. Two days of inconsistent northerlies with confused chop made it a difficult go for all concerned. 10 boats total in attendance. 8 racing.

 

Basically a clean sweep for Mike Costello in 'Dance Commander' - straight bullets except for one close second. Was just about horizon jobbing the fleet all weekend. The bar has been raised. The rest of us have to catch up!

 

Second place goes to Steve Gay, the only guy to beat Mike in a race. Very consistent.

 

Third to John Kells after a very strong push on day two. Mayhem has always had terrific downwind speed.

 

Very nice regatta hosted by Dave Clark despite a broken ankle. Thanks to all the volunteers! We'll be back to the same place next year for North Americans. Hoping for even better things!

 

Onward and upward!

 

-Willy

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I finally got the video coverage of Nationals done. Not the numbers we were banking on. For one thing, two of us had to drop thanks to defective body parts. But even so, eight boats on the line is 2/3 as boats as Moth Nationals, and I'm fine with the Canoe being 2/3 as important as the Moth. Everybody get amped for IC North Americans at Sail Newport this time next year. PM me about charter boats ASAP.

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The NS14 is on the market, time to start lurking around IC Forums again - not long until Wales in 2017 (even less when I need to get a boat).

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The NS14 is on the market, time to start lurking around IC Forums again - not long until Wales in 2017 (even less when I need to get a boat).

Adiction does not go away Christian.

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The NS14 is on the market, time to start lurking around IC Forums again - not long until Wales in 2017 (even less when I need to get a boat).

Adiction does not go away Christian.

Hey Phil, once Christian gets back on the plank and gets his act together and if we can coordinate, now that I have 3 IC's you would be welcome to get some plank action on the log, I might even learn something from you!

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Slowly getting back up to speed in AUS25 (Rat), keep finding small issues that need to be repaired/changed and 25kts plus last week had me err on the side of caution. Hopefully will be able to get a better understanding of what the hull has to offer (the rig doesn't offer much except reefing points - seriously). Then to sit down and make some hard decisions about what to take to Wales in 2017.

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My new IC. Built using flat composite panels pushed into a form. Note the structure built of ACME blem tiller extensions. Also the ACME Laser tillers bonded to the main bulkhead.

Decks go on tomorrow.

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So Chris, did you skin the insides only, then push into the mold/jig, and will skin outside later.

If so how did the foam go on the tight bilge curves. I had been thinking of a similar idea but skinning the outside first, then bending the shell into shape like a stressed ply hull, then skinning the inside, but not been game to try it yet.

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So Chris, did you skin the insides only, then push into the mold/jig, and will skin outside later.

If so how did the foam go on the tight bilge curves. I had been thinking of a similar idea but skinning the outside first, then bending the shell into shape like a stressed ply hull, then skinning the inside, but not been game to try it yet.

Hi Phil. Those panels are laid up on a long glass table (6mm window glass) and after they are cut to shape the smooth, carbon side lays against the mold. Since the carbon is on the tension side of the hull curves you can push in very tight radii. Putting the foam on the tension side would likely turn into a nightmare, unless the curvature was slight, as the foam would tend to crack. After the foam is pushed into the mold the inner skin is applied. You can bag that in if you do a good job of sealing the seams.

To make the panels primer is sprayed on the table, like gelcoat, then, usually, 1 layer of 200gm carbon cloth goes down and foam is bagged onto that. On the IC the panel above the chine can be skinned on both sides on the table since it doesn't have compound curvature. There is a limit to how much compound shape you can force into the panels. The bottom hull panels on an IC are easy. As are most rowing shells. You could probably form an A-cat this way but I don't think you could get, say, the Mach2 Moth hull. I haven't built a tortured ply boat but I'd guess the shape limitations are similar.

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Hey Chris,

Couple of questions. How different is the shape than the boat Mikey won the worlds with? How does it compare with Daves Machete design?

Look forward to seeing more pics. thanks

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Thanks Chris, sounds like you have done my experiment for me. And better that I would have done based on our relatitve records. I guess you need to tape the outside of the chines when you take it out of the mold.

 

I think you could adapt this to the stressed ply method. Skin the foam outside, sew together, spread to double width, tape the chines outside, pull in to design beam, then skin the insides. Shape would be controlled by the sheet shapes, rather than your mold so the curves would be modest.

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Yes Phil, you need to tape the seams. After I spray the primer on the table I lay down three layers of masking tape around the perimeter of the panel using a full size template that gives me a recess along the seams for the carbon tape and saves a lot of fairing. On this IC I tried laying down a tape of peel ply on top of that masking tape and that seems to have worked well.

 

I'm sure your right about using your stressed ply method with these panels. I built a 1m IC model that way and it seemed to work well. Doing that full size was too scary for me though so I chickened out and made that station and batten mold.

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Hey Chris,

Couple of questions. How different is the shape than the boat Mikey won the worlds with? How does it compare with Daves Machete design?

Look forward to seeing more pics. thanks

 

Hi Dave. This boat is very close in shape to the one I sailed at the Richmond worlds and very similar to the String Theory design. It's narrower forward and wider aft than Mikey's. I haven't seen a Machete in person. It seems though that we're all heading in the very wedged shaped waterlines direction and tweaking the rocker distribution to get a hull that smokes in the breeze but isn't too sticky in the light. I wouldn't be surprised if the next UK Morrison design heads in that direction too. Maybe not yet to the point of using the angular sterns that we are favoring in the US though.

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Hi Chris, Its great watching you guys trying innovative new construction methods. Without giving away all your secrets, would you elaborate a little on the trends for rocker and volume distribution?

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My new IC. Built using flat composite panels pushed into a form. Note the structure built of ACME blem tiller extensions. Also the ACME Laser tillers bonded to the main bulkhead.

Decks go on tomorrow.

Thats really cool. How many stations on your mould? I had a quick pop at doing a similar thing with 10mm OX nomex as a way of doing an i14 - did the fwd lower ~2m of the boat i.e. the worst compound curvature. Went ok as a first stab really, 4 stations at 450mm spacing, no stringers tho and that was the main issue a bit of hammocking at the long edges of the panels. Interestingly 200gsm twill skin led to buckling core, 400gsm didn't. Knowing what I know now I would be confident to build a boat this way with 10-15 stations and battens at the edges of the panels (sunk into the frames so flush) Only dodgy part was first 200mm where I'd do it in solid foam knowing what I know now.

 

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Hi Chris, Its great watching you guys trying innovative new construction methods. Without giving away all your secrets, would you elaborate a little on the trends for rocker and volume distribution?

 

I wish I had some secrets to hide! But no, I just make it up as I go. I've added a little rocker - well really it's added curve to the buttocks - of the stern in this new boat to try to keep the stern from dragging at slow speed and to decrease the wetted surface a little too. The trade off will be a little less top end speed. The narrow waterlines forward seem to be faster due, I think, to less resistance in wave encounters, upwind and down. The trade off for that narrowness seems to be a scarier ride on the windier reaches. That's one of the reasons I've been messing with the t-foil on the rudder

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My new IC. Built using flat composite panels pushed into a form. Note the structure built of ACME blem tiller extensions. Also the ACME Laser tillers bonded to the main bulkhead.

Decks go on tomorrow.

Thats really cool. How many stations on your mould? I had a quick pop at doing a similar thing with 10mm OX nomex as a way of doing an i14 - did the fwd lower ~2m of the boat i.e. the worst compound curvature. Went ok as a first stab really, 4 stations at 450mm spacing, no stringers tho and that was the main issue a bit of hammocking at the long edges of the panels. Interestingly 200gsm twill skin led to buckling core, 400gsm didn't. Knowing what I know now I would be confident to build a boat this way with 10-15 stations and battens at the edges of the panels (sunk into the frames so flush) Only dodgy part was first 200mm where I'd do it in solid foam knowing what I know now.

 

 

The stations are about a meter apart. Stringers, at least at the sheer, keel and chine, are essential I think. I wonder if the OX Nomex has enough resistance to buckling? Panels seem to form better if the skin is aligned at + - 45 degrees, which makes sense if you think about how on a compound curve the edges of the panel are trying to compress and the middle to stretch.

Yeah, the bow is tricky. I still haven't got that completely figured out. I have been tapering the foam core at the centerline in the bow with a belt sander to get it to bend that tight radius consistently.

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M3 Progress & Comparison with M2

 

Pictures of M3 plug & comparison with an M2 shell attached (please don't look too closely at the shell - this one became a "practice" moulding!). M3 finer in bow with fuller sections aft, but retaining curved stern as Chris suggests.

 

Deck mould is done & few days work on hull plug should see us setting up to take the moulds off. Centre line split with the foredeck moulded in. Using horizontal "U" channels moulded with the topsides for the carriage rails (thanks Arne!).

 

...thought this might provide some diversion from festive over enjoyment.

 

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While we are all admiring each others bottoms.......

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This is the rendering of the Gaigin design.

Only known example is Dance Commander, which is US national Champion this year.

We are winding up to build a few of these using something like what Chris has done.

We have a good fixture which was CNC cut with stations every 200mm or so.

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This should keep the bulges down, but I was still a problem when I tried to deform un-skinned 6mm foam. I wanted to bag the outside skin onto the foam after the interior was all in place. This would have given me the chance to fair the foam ( if necessary) instead of having to fair outside the carbon skin.

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Upon further review, I think using a ply of carbon on the foam is the right move, but I am going to use peel ply over the whole thing as well.

I'm also going to spray PlastiDip all over the gig so I can glue the skin to the jig for as long as I need to and till be able to peel it out.

I expect to win big.

SHC

 

 

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Some Questions to the knowledgeable on this forum?

 

1. For the newer designs, with the really pointy bows, how often do you spend with the carriage all the way forward, and in what conditions is this, I am guessing it is the really light stuff, but for everything else you are way down the back?

 

2. Has anyone (except phil stevenson's hollow log which is now my hollow log) built a minimum beam IC without stays or without the little "winglet" stay mounts? Is this problem not worth solving without the winglets?

 

3. Has anyone built an IC with a pointy bow right back to the BMS all the way back at 1300 mm from the stern, such that everything fwd of the 1300BMS is pointy goodness?

 

Eventually the log is going to wear out, and I am conceptualising a replacement...

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Something like this, mast moved a long way back, countered by the skinny fwd bit, but moving mast aft also allows shroud base 666 mm, really pointy front all the way back to compliant BMS at 1300mm from stern. Narrow carriage about 700mm wide to have a little bit of fore aft movement from just aft of daggerboard, I go under the boom anyway, as the log doesn't have room around the back, and this way has stuck with me on the nethercott this year. I think it would be a little more difficult to sail than the log... But could potentially be built in a similar way, with extra reinforcing around the mast stays and carriage,

 

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What do you think? Am I way of the mark here or would it be even scarier more awesome ride than the log?

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As an interested observer. At what point is the bow TOO narrow so that it's not doing any work at all?

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"What do you think? Am I way of the mark here or would it be even scarier more awesome ride than the log?"

 

 

 

 

You win! Your half entry angle is about 6deg. Mine is a plump 7deg. Go for it.

 

I suspect that your ass will be a little draggy in light wind - you're right, I have my seat carriage right forward in light wind, especially downwind. I think too that you will wish you could move your carriage to about a meter behind the rudder on windy reaches.

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You win! Your half entry angle is about 6deg. Mine is a plump 7deg. Go for it.

 

I suspect that your ass will be a little draggy in light wind - you're right, I have my seat carriage right forward in light wind, especially downwind. I think too that you will wish you could move your carriage to about a meter behind the rudder on windy reaches.

I like you style and your positive attitude Dr Mass! Can't wait to see one of your boats in person!

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As an interested observer. At what point is the bow TOO narrow so that it's not doing any work at all?

The thing is, as the bow gets finer and finer, wave drag gets less and less important, so it becomes less and less important how much work the bow is doing. Take a good look at some of the on line videos, especially those in moderate to light conditions, and take a good look at the wave systems the boats throw up.With a Nethercott you'll see the bow pushing up quite a wave system, but with the new ones its almost as if the boat is hardly generating waves at all. However you've still got to displace some water somewhere so if you go too far on the fine front you'll be dragging too much ocean behind you with a podgy ass.

How much is too fine? Excellent question: no doubt we'll find out in the next few years, but the general intent of all the stuff in the rules Steve spent time working on is that to an extent the designer will be protected from really overcooking it.

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theoretically, with all that skinny bow doing nothing, might it be better to not have that bow at all?

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theoretically, with all that skinny bow doing nothing, might it be better to not have that bow at all?

No, don't reckon so, because it isn't doing nothing. What its doing is cleaving the water, even if it does it without doing much wave generation. If you shortened the bow then you'd be left with a much blunter entry which did kick up a bow wave and gave you loads of drag. This would not be an improvement. Well, not most of the time. If you consider sailing in under 1 knot of wind, when drag is dominated by wetted area, then a long fine bow gives you a fair bit of wetted area for not much displacement, and then it isn't helping. Everything is a compromise!

 

On reflection that first post should have said something on the lines of "as the bow gets finer and finer, wave drag gets less and less important, so it becomes less and less important how much work the bow is doing in terms of making a longer a wave system".

 

The IC is a very interesting design space which is somewhere between a conventional monohull and a conventional catamaran hull. Subject to correction by the real experts here, I'd say that in wave drag and displacement and lower speed behaviour its more like a multihull, and at high speed and considering dynamic lift and planing then its more like a monohull.

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The IC is a very interesting design space which is somewhere between a conventional monohull and a conventional catamaran hull. Subject to correction by the real experts here, I'd say that in wave drag and displacement and lower speed behaviour its more like a multihull, and at high speed and considering dynamic lift and planing then its more like a monohull.

 

 

that's probably key here. As I understand it, performance cats have gone to fuller bows, higher prismatic coefficient, even though the overall shape is still very skinny. they never "plane"

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Chatting to SEZED offline, my concern with the finer bows is more the logistics of safely getting on and off the beach (aesthetically I think they are awesome). There isn't always a support crew around, and the more fragile things are in the ends the more chance there is to have to be spending my non sailing time filling and fairing.
Launching and recovering I often suffer finn envy, where skippers just lower their centreboards and calmly drop their mains right near shore whilst I balance an ICin the surf break and try to attract someones attention to grab my trolley :)

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This is always my biggest problem, fortunately there is often some one about to hold the boat when rigging in a strong wind(or else it capsizes on the trolley) and when recovering the club has put a rope down the middle of the slip which I tie the end of the seat to and the boat then is surprisingly stable. As far as narrow bows go then as narrow as possible I think, transom is a little more diffcult, fat for planing or narrow for low drag with a T-foil perhaps? As to rig position you can go too far back, I think 1.9 to 2.2m from the bow in my mind seems to be the limits.

Hope to see you both in Wales?

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I'd argue that the "pintail for low drag in light air" argument ignores the fact that bows can be sunk and sterns lifted by getting forward, thus eliminating much of the drag off the stern, so long as the boat has sufficient rocker. The thing that strikes me more than anything else about maxi-boating the rig further and further aft is that it reduces the sailors capacity to get forward of the center of buoyancy and thus realize the potential of such a bimodal hullshape. That and you'd have trouble getting the full benefit of waterline as you drive to windward in chop. You end up with a lot of wave piercer just sitting in the air.

DRC

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I'd argue that the "pintail for low drag in light air" argument ignores the fact that bows can be sunk and sterns lifted by getting forward, thus eliminating much of the drag off the stern, so long as the boat has sufficient rocker. The thing that strikes me more than anything else about maxi-boating the rig further and further aft is that it reduces the sailors capacity to get forward of the center of buoyancy and thus realize the potential of such a bimodal hullshape. That and you'd have trouble getting the full benefit of waterline as you drive to windward in chop. You end up with a lot of wave piercer just sitting in the air.

 

DRC

In light wind I agree. That is why I've moved my mast 75mm forward and increased the rocker aft on this new boat.

 

A t-foil on SEZED's rudder would push his bow back down however. Looking at pictures of the Richmond worlds my bow seems to spend a lot of time out of the water. I think that maybe once your speed is getting up over 10kts or so you're not looking for waterline length so much.

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Jim C says: " The IC is a very interesting design space which is somewhere between a conventional monohull and a conventional catamaran." The Supermaxi hulls are now in or approaching the same design space as the IC. Wild Thing formerly Skandia ( Donan Raven's Sailing Trivia) has a hull length of 30 m with a beam of 4.95 m and a displacement of 26 metric tons. An IC scaled to 30 m would have a beam of 4.3 m and a displacement of 25 metric tons. Not really all that different.

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Yes, I agree that there are also plenty of differences. Stability of a hull (heeling) scales as the cube of the length for the same shaped hull, which is why the canoe needs a crew on a seat, (equivalent of about 12 meters) if scaled up to 30 m LOA whilst the maxi can carry a sail area greater than the scaled 10 sq m of the canoe. I don't know what speeds the maxis sail at but the Froude number is probably similar, 10 knots for the canoe is equivalent to about 25 knots for the maxi. Reynolds numbers will be different, with that for the maxi being much higher. Scaled up the 10 sq m would be equivalent to about 330 sq m rather than the 492 sq m for Wild Thing sailing upwind. Driving force probably scales as the square of the length, as does the sail area, at any particular wind speed, but if everything is scaled so should the wind speed, thus a canoe sailing in 16 knots of wind would be more similar to a maxi sailing in 32 knots of wind, and the driving force to displacement will be similar for both boats.

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Chatting to SEZED offline, my concern with the finer bows is more the logistics of safely getting on and off the beach (aesthetically I think they are awesome). There isn't always a support crew around, and the more fragile things are in the ends the more chance there is to have to be spending my non sailing time filling and fairing.

Launching and recovering I often suffer finn envy, where skippers just lower their centreboards and calmly drop their mains right near shore whilst I balance an ICin the surf break and try to attract someones attention to grab my trolley :)

 

 

The Log is quite pointy, and I struggled enormously launching on my own, though now I have it down to a fine art. Place rudder and centreboard on boat under carriage. Put trolley and boat into the water, float the canoe off the trolley. Capsize it with the plank, mainsheet and tiller extension in just the right spot and let it float. Throw the trolley ashore ASAP (the hardest part), slide centreboard and rudder into their slots, right the boat(the log is VERY easy to right from capsize - significantly morso than the Nethercott jumping straight from centreboard onto boat/plank and sail off) - this is the only way that has worked for me I think I tried every other possibility. The return to shore is pretty much the reverse, except that I strap the trolley to the canoe in the capsized position with the centreboard and rudder removed and right it using the plank and pull it straight up on the shore. The Nethercott this season has proved much easier to launch and is significantly more stable. I quite often drop the main before entering the basin and jib it back ashore with the Nethercott. The log inevitably involves capsizes, but it is super easy to right straight away.

 

I have found that well meaning people who want to help seem to just get in the way, they don't quite follow my system which is working for me and it tends to get much more complicated when people help. Really I just want someone to take and fetch the trolley - leave everything else to me and I will figure it out! I imagine this is how it work with a newer skinnier hull... wrt damage, i have done pretty much everything to the log, and it has survived my abuse so far, and i mean, a lot of abuse. The worst was real early in the piece I forgot to tie the plank limiter on and it slipped out of one side of the carriage upon launching and capsize, with and almighty bank and a massive crack in the carriage forming where the plank was twisting and loading it up in completely the wrong way with only the fulcrum bit of the plank being secured in the carriage... I was horrified, but went sailing anyway - and the carriage has been like that complete with horrible crack ever since, and is still holding up fine. This is 3mm stressed ply with carbon reinforcing in the right places and it is going on 9 years old - one of the oldest new rules boats and it is still going strong, even if it is in the shed waiting for some preventative wood protecting maintenance, So I think that a well constructed pointy boat should be plenty strong enough :-)

 

Of course, this is probably more difficult where you sail or if there are breaking waves or rocks or similar...

 

Stefan

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Thanks Dave and Chris for your insights.

 

I tried to use rhino to figure out centres of buoyancy and that stuff - but I couldn't quite get it to give me sensible answers, So I guess I will have to (eventually) build it and see how it goes... maybe I will prototype it with inbuilt flexibility to move stuff around before settling on a weight saved final solution :-) What I can say though is that it looks like the centre of buoyancy would be a fair bit further aft due to the skinnyness... Of course I am not a designer or naval architect, just doing this because one day I would love to design and build a boat myself, until then I will continue to play with the log and my Nethercotts...

 

FWIW I have nosedived the log quite spectacularly on a number of occasions - and I though this was when I was aft on the carriage, so I guess this contributes to my thoughts on moving stuff back. I do note however that Phil has said in his early posts that he didn't really ever nosedive it - Phil is a much better sailor than I am though.

 

I tweaked my design a bit - extended the chine all the way forward allowing for smooth flowing pointy curvyness....it looks slippery. Rocker and horizontal surface area back aft to promote planing. Probably pretty unstable and hard to sail, but can't be too much worse than the log, trying to get everything a bit lower, the log is quite high on the freeboard.

 

ConceptMk2-2Side.jpg

ConceptMk2-2TopBow.jpg

ConceptMk2-2STBD%20QTR.jpg

ConceptMk2-2PortBow.jpg

 

Oh and Chris - I think I measured the half entry angle to be about 5.5 degrees :-) may be a little tricky to do that in reality. I think this tweaked design now rules out stressed ply - perhaps a jig/plug/mould/layup - could keep me entertained for ages!

 

Stefan

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I'm not sure about rocker aft promoting planing. In other classes I've been involved with its tended to be characterised as safe-but-slow. But the canoe does march differently!

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Yeah that bit is probably not as important in this case as the key feature of this concept design which is the extreme pointiness for wave piercing, that's what I was focusing on ...

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One thing that is fun is to make models and do comparative testing. You make two models, and tow them off a yoke. The best one wins by going ahead of the other one. Do you have old towpath canals down there like we have here? Perfect for that :-)

 

 

Models are definitely on the cards!

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Something like this, mast moved a long way back, countered by the skinny fwd bit, but moving mast aft also allows shroud base 666 mm, really pointy front all the way back to compliant BMS at 1300mm from stern. Narrow carriage about 700mm wide to have a little bit of fore aft movement from just aft of daggerboard, I go under the boom anyway, as the log doesn't have room around the back, and this way has stuck with me on the nethercott this year. I think it would be a little more difficult to sail than the log... But could potentially be built in a similar way, with extra reinforcing around the mast stays and carriage,

 

ba24581c7f2236ebf04f6714e048b17f.jpg

10753c3d409e5afc0d7e704ccb188ac1.jpg

6fcc221bc0342c49d703d379f361db5a.jpg

136c57c9bd64e9931da930c0fd9dd19f.jpg

 

What do you think? Am I way of the mark here or would it be even scarier more awesome ride than the log?

Important question: have you calculated the volume on this hull? The Machete design is practically a straight line back to a max aft BMS and the first iteration of the design came in under volume. It took double-chining it to a dead flat bottom get proper buoyancy and planing ability out of it. And that hull doesn't have a pintail stern. Mind you, a huge T-foil can eliminate any shortage of buoyancy, so it's not an issue in a straight line.

 

DRC

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Dave, Volume does sound important, I think I will need to look at that closer if and when this goes ahead.

 

Andrew, it basically is a crazy diamond, but with supple curvieness and parabolas instead of straight edges...

 

Stefan

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Stefan, post a table of offsets and I can do a quick estimate of C of B, Waterline position and lift versus speed. I wrote a simple programme based on a multi (up to 5)chine hull. Nothing like as sophisticated as Rhino, but much easier to use, for me at least. I didn't want to spend the time learning to use Rhino or other yacht design programmes.

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With the mast step moved aft it may be difficult to get the sailor's weight forward. If you can't immerse the very fine bow, why have it? I would expect less and less rocker as the mast step moves aft. A GNAV could help get forward but going down wind the daggerboard is pulled up and defines the location of the carriage.

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Damn. It looks like a hole in the universe...

Nearly....

 

Hole in the universe with strange rack mounts

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A really refined aesthetic, Chris. Beautiful.

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Hot.

Or will be whenever the sun is out.

What resin? Nice high HTD I hope.

SHC

Vents built into the hull to avoid explosions? It's that colour to minimize the wet weight you carry around in splashy conditions, it'll all evaporate right off...

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Hot.

Or will be whenever the sun is out.

What resin? Nice high HTD I hope.

SHC

No sun expected this summer.

For the future, installation of integrated water cooling system foreseen for on shore operations.

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How about a couple more pics. Can't get over how much finer that bow looks. Need to see the back to put it all together. Stunning pic. Very nice

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Paint's dry.

Holy Smokes ! Johnny Cash Black is always in fashion

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