stinky

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Just enough time for a test sail before putting her on the trailer for the Nationals in Richmond the weeekend of the 15 & 16 of Sept.

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However the "V" shaped piece of equipment in the second illustration would not pass, failing the "spirit of the rule" test.

AND the 50mm width rule.

 

Personally, i'm not sold on the value of the bit sticking out the back.

The trailing edge of the rudder at that height is pretty strong, usually it's the tip part that gets chipped up.

And I wouldn't think that dragging that tail around would appeal to me.

Of course it all depends on how cool the roster tail looks.

 

I also think that in the event of a grounding, the bits are going to get as mashed up as any of the alternatives, so don't really think I would have done it that way.

 

BUT this is one of the nice things about ICs, you can exert your brain to come up with different solutions, which even if not better are YOURS.

 

I'm thinking there will be RI trailer headed to the Nationals. Room for some boats for those who want to get cold and wet in Richmond.

Space is limited so sign up now.

Divers wanted.

SHC

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OK so this Driver needs to charter a trusty steed for the nationals. Anyone? My truck and boat are in Ohio waiting for the HPDO in New York in October.

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Well it appears that I may have acheived the crudder trifecta of slower, more vulnerable to damage and uglier. One trip through the saw could cure all, but not now.

 

I'm not going commit to a cross country journey until I gain some confidence in my boathandling. The last time I sailed in SF it blew 25+.

 

Two coats of topcoat:

 

post-32376-094297300 1344812541_thumb.jpg

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Hey Crap,

Unless you're Usain Bolt, confidence is relative and somewhat over rated.

It's mid Sept and thou it can blow, it's much less likely to be nukeing.

 

What's the Tale of the Scale showing?

Keep us posted,

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Well it appears that I may have acheived the crudder trifecta of slower, more vulnerable to damage and uglier. One trip through the saw could cure all, but not now.

 

I'm not going commit to a cross country journey until I gain some confidence in my boathandling. The last time I sailed in SF it blew 25+.

 

Two coats of topcoat:

 

post-32376-094297300 1344812541_thumb.jpg

 

Holy Crap!

 

That looks great, though there is no way they won't know it was you over at the start

 

Enjoy,

 

Fish

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Holy Crap!

 

That looks great, though there is no way they won't know it was you over at the start

 

Enjoy,

 

Fish

 

Thanks Fish. The plan is to blend in with the orange pin, or blind the race committee.

 

Del, I don't mind embarassing myself but I need to be capable of sailing out to the course and back without damaging anyone's boat, including yours. I have had fun sailing Lasers, windsurfers and big boats in nuclear conditions just need to learn the IC handling tricks.

 

The weight spreadsheet says between 2 and 5 pounds under, but the hull hasn't been weighed since it was in parts, and there is the question of cow scale accuracy. Light is good, after the first sail modifications may be required.

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El Crap,

Embarassing yourself is part of the experience, sometimes it's more fun in the company of others on that same path. I have a laundry list of misadventures , from under engineered rudders to untested boats heading for the start line of a major race.

It's a good call to do it the right way and be prepared. If not for the Nationals the for the North Americans next year, I think they're scheduled to be in your corner of the country.

The Pix look good and if you're looking to add some lead , a really good job building. and no comments about orange peal paint jobs, Please

Cheers

Holy Crap!

 

That looks great, though there is no way they won't know it was you over at the start

 

Enjoy,

 

Fish

 

Thanks Fish. The plan is to blend in with the orange pin, or blind the race committee.

 

Del, I don't mind embarassing myself but I need to be capable of sailing out to the course and back without damaging anyone's boat, including yours. I have had fun sailing Lasers, windsurfers and big boats in nuclear conditions just need to learn the IC handling tricks.

 

The weight spreadsheet says between 2 and 5 pounds under, but the hull hasn't been weighed since it was in parts, and there is the question of cow scale accuracy. Light is good, after the first sail modifications may be required.

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Rule author here.

Let me make it unambiguous.

The "Crudder" is a legal arrangement.

It is a rudder fitting and is less than 50mm wide.

In fact it could be a meter long and it would be legal.

It would also be slow, because 50mm x 1000mm lined up with the flow isn't big enough to provide any meaningful bouyancey and will do nothing to improve the wave making resistance and will add wetted surface.

I question the merit of the little bit of end plate, which really doesn't have to extend beyond half chord to be effective.....but that doesn't make any difference, the option was considered when I wrote the rule and I determined that there would be no speed advantage to this fabrication. There are some structural advantages, which make hanging a rudder on a tiny stern easier, if one is so minded. The biggest benefit may be to allow the tiller to be just a bit longer and or to have just a bit more room to move your feet when all the way back in the bus.

That's why we wrote the rule this way!

Before we call you a genius however, I want to see how badly the stern and or cassette get mangled by running into something.

SHC

 

Steve,

 

Thanks for helping put this to bed. I stand corrected.

 

John

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Hi Guys,

 

I am new to the sailing canoe seen and have picked up NZL2 an old nethercott deisgn. I am slowly getting it uo to speed. Can you advise what size rudder is best for this design? As the one it came with looks a bit small and I think it may be a bit shorter than it should be.

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As the one it came with looks a bit small and I think it may be a bit shorter than it should be.

The under the boat (as opposed to transom hung) rudders typically look bloody ridiculously small. Part of that is the optical illusion of having no stock, and more of it is probably the extra efficiency of having effective end plating so ventilation is practically impossible if the boat is anywhere near flat, and yet more of it is probably the long lever between plate and rudder. But even allowing for all that mine still looks comically small and short to me yet still works.

 

So don't worry about it!

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Thankyou gentlemen,

 

 

I shall make it a tad bigger than what I've got as its easy to chop some off, as opposed to add some on.

 

will let you know what sort of wiggle factor it has.

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Hull 252 launched yesterday!

 

Before filling in the details, I need to give credit where credit is due. First to John Kells who has provided quality advice to me free of charge for the better part of a year. Yesterday he rolled up his sleeves and fixed numerous rigging problems when he could have rigged his own boat and gone sailing. Second to Steve Clark for providing a 3mm headstay to replace my undersized 1.2mm one before it broke. Steve also fixed my riveter. It wasn't really broken so fixing it was easy for him. Willie helped too, offering Steve's 40# Big Daddy riveter to install a 1/8" pop rivet. Willie really did help, joining in with John on the rigging. And thanks to Kim for dinner afterwards.

 

I arrived at Point Farm an hour early to perform boom surgery with the shock cord that can't be bought where I live. And to rig. I am a total newby and rigging takes me forever, partly because I take things apart at the wrong places. I didn't forget any parts, which helps, or any tools, which also helps. The rack on the car held both coming and going. I'm going through the short list of things I did right. I was so slow at rigging that at one point Steve, Willie and John were rigging it. I was helping, sort of.

 

Eventually 252 was ready. Willie grabbed a bottle and a camera. While Willie focused the camera, Tristan the dog snuck into the picture and dropped a deuce. Uncanny. The cork popped and the boat and owner were sprayed with champagne. I had to cough up a name. Kraptonyte came out, but maybe Deuces would be more appropriate.

 

Then I launched. Steve pushed me into the Kickemuit with John showing me where to go to not hit bottom. For the first minute or two things were seemingly ok. I sat out on the seat a bit, main and jib were drawing. I trimmed them a bit. The carriage slid forward on its own so I need to add a brake. Then I sailed into a lull and scrambled to leeward and even grabbed the boom for a pump but to no avail. I slid off the boat and stood on the bottom and rerighted. After sort of getting going again I had to tack and went back in. Another reright but this one was different, there was a bit of a crack noise. After that there was more crack noise than sailing. The crack noise was coming from the crack in the daggerboard. I made the board almost 4 years ago out of carbon over a spruce core. I think I put enough carbon on the board but sanded too much off and that was the problem. The sail was over. All that was left to do was to walk back across the Kicke to the launch ramp, boat in tow.

 

This morning I update my to do list. I've been working down this list since May.

post-32376-0-07347200-1345819982_thumb.png

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he crack noise was coming from the crack in the daggerboard.

 

Oh how very irritating. Congrats on getting on the water, if only briefly.

 

I'm reminded of an incident at a champs in another class some years ago

 

Previous evening in bar: "I can't understand how [redacted]'s foils haven't broken. They're exactly the same layup as my ones which broke"

Next day on race track: "crack"

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I had the same problem at a leukemia cup reggatta, seems when you don't stand on board much you don't know how easily it will break! Better to over build than be lightest.

 

Congrats!, now pix plz!

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hey Cats,

my Canoe, Can 39 is for sale.

for those who don't know it, this is the prototype Super String Theory, built by Chris Maas from which the molds were made for the SST boats that Chris is currently building. it is a proven fast boat, faster than the helm.

the sails are very good shapes in very good condition, not having much time on them. main by Graham Herbert, Kinder jib.

mast is the latest high modulus van Dusen.

daggerboard by Bieker, in a gybing cassette, swing up rudder by Chris.

most lines Maffioli

housed in a very light, very aero trailer, which keeps the boat dust free in the most horrific road conditions. the trailer has custom made soft springs and new hubs carrying balanced 12" wheels and radial tires.

I'll send fotos by email, until I figure out how to get em on this site.

not at all sure it is appropriate to advertise my boat in this way.

cheers, Kenny

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a contact email is agtfree1@hotmail.com

I can meet halfway, or do a full delivery if fuel costs are covered.

price is $15,000 Cdn

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a contact email is agtfree1@hotmail.com

I can meet halfway, or do a full delivery if fuel costs are covered.

price is $15,000 Cdn

 

Out of curiosity- Have you paid SailingAnarchy for an advertisment?

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Congrats!, now pix plz!

 

Here's a picture of my crack:

 

 

 

 

 

 

 

 

 

 

 

 

 

post-32376-0-49262500-1345908203_thumb.jpg

 

We need pics of the boat and of Tristan pooping.

 

Willy has them.

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That's really unusual - can't offhand remember seeing a board fail with lengthways cracks like that.

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a contact email is agtfree1@hotmail.com

I can meet halfway, or do a full delivery if fuel costs are covered.

price is $15,000 Cdn

 

Out of curiosity- Have you paid SailingAnarchy for an advertisment?

no! didn't know they had a for sale section! if so, I'll check it out.

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a contact email is agtfree1@hotmail.com

I can meet halfway, or do a full delivery if fuel costs are covered.

price is $15,000 Cdn

 

Out of curiosity- Have you paid SailingAnarchy for an advertisment?

no! didn't know they had a for sale section! if so, I'll check it out.

 

To help you out, try this link http://www.sailinganarchy.com/classified.htm

 

Good luck with selling it.

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sorry about the gate crashing folks, I found classifieds under 'features'. will put an ad in there.

Kenny

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Well it appears that I may have acheived the crudder trifecta of slower, more vulnerable to damage and uglier. One trip through the saw could cure all, but not now.

 

I'm not going commit to a cross country journey until I gain some confidence in my boathandling. The last time I sailed in SF it blew 25+.

 

Two coats of topcoat:

 

post-32376-094297300 1344812541_thumb.jpg

 

the wall posters are nice ;)

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a contact email is agtfree1@hotmail.com

I can meet halfway, or do a full delivery if fuel costs are covered.

price is $15,000 Cdn

 

Out of curiosity- Have you paid SailingAnarchy for an advertisment?

no! didn't know they had a for sale section! if so, I'll check it out.

 

To help you out, try this link http://www.sailingan.../classified.htm

 

Good luck with selling it.

ad in in the classifieds soon, I hope. paid for...

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Just a reminder that the deadline for HPDO registration without incurring the $40 late fee is September 1.

 

Looking forward to seeing Big Dave & others.

 

By my count we could easily have eight boats on the line.

 

Who is in:

 

Steve

Willy

Dave

Bill

Big George

Eli

El Crapitano

Big Dave

Robbie

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I'm in

 

Just a reminder that the deadline for HPDO registration without incurring the $40 late fee is September 1.

 

Looking forward to seeing Big Dave & others.

 

By my count we could easily have eight boats on the line.

 

Who is in:

 

Steve

Willy

Dave

Bill

Big George

Eli

El Crapitano

Big Dave

Robbie

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After a long winter off, playing Ice Hockey mainly, it is time for the IC to hit the water again. If it all goes well I'll post pics, if not then we'll all know that my lack of sailing and maintenance this winter may not have been the best approach :D

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Hey, HPOD report--who's on it?

 

Nationals... Del vs Me... I'll give my report when I hear about yours.

 

Let's find some regattas for the upcoming year and make some commitments, shall we?

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I am working on some new hull ideas and wanted to compare the stability of them compared with my previous efforts. Not sure what the best approach is. I had done what I thought was a far more stable design but when I looked at how the center of boancy moved when I healed it there was very little difference to Dragonfly although the new design was max width, any suggestions?

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I am working on some new hull ideas and wanted to compare the stability of them compared with my previous efforts. Not sure what the best approach is. I had done what I thought was a far more stable design but when I looked at how the center of boancy moved when I healed it there was very little difference to Dragonfly although the new design was max width, any suggestions?

 

If you still have the minimum waterline beam but flare the topside to maximum beam, it may not alter the stability much. But it does give you more dance floor, which gives you a greater margin for error. The problem with a minimum beam hull, coupled with the minimum freeboard restriction, is that when the boat heels you quickly reach the point where standing on the gunwhale is not enough to right the boat i.e. your centre of gravity is very close the transverse centre of bouyancy. Making the deck wider just allows you to stand further outboard. The boat can then heel further before you reach the point of no return.

 

If you want to actually make the boat more stable, you have to increase the waterline beam and sacrifice wetted surface area. There's no way around it.

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I am working on some new hull ideas and wanted to compare the stability of them compared with my previous efforts. Not sure what the best approach is. I had done what I thought was a far more stable design but when I looked at how the center of boancy moved when I healed it there was very little difference to Dragonfly although the new design was max width, any suggestions?

 

If you still have the minimum waterline beam but flare the topside to maximum beam, it may not alter the stability much. But it does give you more dance floor, which gives you a greater margin for error. The problem with a minimum beam hull, coupled with the minimum freeboard restriction, is that when the boat heels you quickly reach the point where standing on the gunwhale is not enough to right the boat i.e. your centre of gravity is very close the transverse centre of bouyancy. Making the deck wider just allows you to stand further outboard. The boat can then heel further before you reach the point of no return.

 

If you want to actually make the boat more stable, you have to increase the waterline beam and sacrifice wetted surface area. There's no way around it.

 

Thanks, you have guessed where I was going with that, I have taken Dragonfly's under water shape and flared from that, which worked out as just extending the small chine I have, then I nipped in the bow a bit to end up with .. well I would have attached a photo but I am not sure how, the forum has changed since I last posted an image!

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Probably doesn't help what with your design's evolutionary approach, but as a very simple example, a max beam square chine flat bottom double end hull with a lowish prismatic, while having around 38 sq ft of wetted surface upright can get down to 28 sq ft of wetted surface at 10-15 degrees of heel. Without foils. Buoyancy moves sideways a lot. Kind of a Formula board with streamlining. :) 2.6" of rocker. A lot of square feet overall for the whole hull. Hard to get it light? Numbers above based on displacement about 285 lbs. with sailor.

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If you slice off the sides longitudinally, say 2" in from the gunwales, on Dragonfly, and leave them in place (like taking out the mid section of the hull and leaving the sides of the hull looking like a skinny catamaran, and then do the same with the green hull at the same point out, and then look at the resultIng 'hulls' from the front or back, with the waterline in place, I think you'll see what's going on, especially if you're looking for initial stability (like when tacking?). It would help even more if you can rotate around the longitudinal axis with the waterline showing as influenced by the changing volume.Maybe if you made the inside gunwales of the green boat thicker, so you could heel into some volume, while leaving a nice low dance floor. That would be like making the hulls of the skinny catamaran more floaty, instead of water coming over a skinny edge and into the boat easily. Would just take some longitudinal strips of foam temporarily glued down on the inside of the rail to test. Given the skinny nature of the green boats rail, you might even add some floatation a bit lower at progressive angles of heel by doing this?

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I meant to do this on a computer, with design software.

 

Oops.

 

 

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Thanks, you have guessed where I was going with that, I have taken Dragonfly's under water shape and flared from that,

I was looking at the mould (and the Maas and Morrison) yesterday and I really don't know how you're going to get any great difference in stability without a major change in the underwater shape.There doesn't seem to me to be enough volume available low enough down for flare to make much difference.

 

One of the things that bemuses me is that, from what I can gather, historically minimum beam Canoes have not necessarilly been regarded as quick - the Nethercott was some way off minimum beam and so, of course, were Uffa's boats. However since we've gone back to the box rule everyone has gone minimum beam, and when I draw stuff on the PC and look at the numbers they are yelling at me that thin is the way to go.

 

So what's changed? Maybe I should push drawings from the 1930s onto the box and see what they tell me? One big thing of course is that rigs must weigh a fraction of what they used to, and that must have a big effect.

 

I wish I was brave enough to build a wide boat and see what happens, but the trouble with radical experiments is that, unless you are a front of fleet sailor or can persuade one to sail your design regularly, you really have no way of finding out whether the concept works or not because the boat is such a small part of winning races, and even were I fit I just don't steer boats at the required talent level.

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I don't think a wide hull is ever going to be faster than a narrow one. The numbers aren't wrong. If you are really serious about winning, build the narrowest hull you can with the lowest wetted surface and learn to get it around the course.

 

But for those of us who are less serious about winning and/or haven't got the time or the will to put in the necessary practice (or who are just getting old and worn), there is the option to go for a wider hull. If that is enough so that you can get around the course upright more often, the result may be an overall improvement in your personal performance, not to mention greater enjoyment of the sailing experience than if you spend most of it swimming. A wide canoe may not be super quick compared to a narrow canoe, but it sure beats a Laser, if not just about anything else!

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The difference between now and then is the weight of the rigs and the proficiency of the sailors.

Read the reports if Uffa and you hear things like " fast but too hard to sail."

Getting pounds out of the air has certainly changed the game, but so has the expertise of the sailors.

We all sail things that would have been inconceivable 50 or 60 years ago because we have gradually learned how.

The Nethercott was a conservative design from the mid to late 1960s. It predates a Laser.

 

I think more important than the stability is the rate of change. A bit more flare, I think, will slow the roll rate and a bit more beam on deck will allow more righting moment to be applied before committing to the seat. Both may be worth it making the boat easier to sail at full potential even if that potential is slightly lower than the minimum beam boat.

 

I wonder if a boat with enough deck beam to accommodate existing Nethercott seat carriages wouldn't be a good idea.

 

On the other hand, put the time in and figure out how to sail the skinny one is a pretty good strategy. It's not like going sailing on an IC is unpleasant.

SHC

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I wonder if a boat with enough deck beam to accommodate existing Nethercott seat carriages wouldn't be a good idea.

Andy and I were mulling over that too yesterday...

I was looking at the black needle taking shape and wondering if I could have hacked it even if other factors hadn't intervened.

I've certainly been thinking a bigger dance floor ought to be beneficial, but, as I've discovered with my fat stern Nethercott, you need then more freeboard to keep draggy bits out of the water if you heel, so then you've got more structure and weight, and several factors are going in the wrong direction.

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I wonder if a boat with enough deck beam to accommodate existing Nethercott seat carriages wouldn't be a good idea.

Andy and I were mulling over that too yesterday...

I was looking at the black needle taking shape and wondering if I could have hacked it even if other factors hadn't intervened.

I've certainly been thinking a bigger dance floor ought to be beneficial, but, as I've discovered with my fat stern Nethercott, you need then more freeboard to keep draggy bits out of the water if you heel, so then you've got more structure and weight, and several factors are going in the wrong direction.

 

From Memory Scarlet Ohara used a nethercott plank and carriage and stay base and looks fast :)

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Rule Question-

 

It's been hard for me to see in pics-

 

If you were to take the max fullness stern at 1/2 angle 45 degrees, does the intersection of resultant straight stern lines with the gunwale have to be radiused at 4" in planform view?

 

It looks like the stern can be a 90 sharp edge in profile view (like a hard chine) as it seems the resulting stern surface, going forward, vertically, can exist as if it were cut off as clean face on the angle from the stern to the point where it meets the gunwale coming back?

 

Do the 2 overlap? I can see a gunwale angling suddenly down to the stern in profile being an angle, but in planform it would have to be Radiused?

 

 

 

 

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Rule Question-

 

It's been hard for me to see in pics-

 

If you were to take the max fullness stern at 1/2 angle 45 degrees, does the intersection of resultant straight stern lines with the gunwale have to be radiused at 4" in planform view?

 

It looks like the stern can be a 90 sharp edge in profile view (like a hard chine) as it seems the resulting stern surface, going forward, vertically, can exist as if it were cut off as clean face on the angle from the stern to the point where it meets the gunwale coming back?

 

Do the 2 overlap? I can see a gunwale angling suddenly down to the stern in profile being an angle, but in planform it would have to be Radiused?

 

Yes, it has to be radused in planform. I think it's a 60mm radius, which is quite small. You could probably build it as a sharp corner then make it fit the rule with filler and sandpaper. Or build small gunwhale over the corner and radius that.

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Yeah, the radius is not hard to achieve. Indeed when I put the full stern on my Nethercott I clean forgot about the existence of the rule, but when I'd checked discovered that I'd complied with it anyway just rounding off the wood capping/gunwhale that protects the edge of the ply deck.

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So, in practice, if the corner (which is the side of the hull) was, say, 4" in thickness vertically, the rule would be met by rounding the gunwale stripping on the top of it? And leaving the corner intact? That seems agreeable....

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Yes the projection must have the radius etc, but it can be gunwale or bottom or sides.

On the Maas boat I'm doing, there is a flat panel at ~ 45° to vertical, so the projection of the transom is gently curved due to the bottom curvature, and a bit at the chine I'm going to have to fiddle with to meet the radius - but it's only a tiny bit in reality . A CD is exactly the right size for checking this radius.

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I knew those cd blanks I have littering my basement would come in handy......

 

 

Throw them away indeed. Humph.

 

Thanks guys.

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Pictures of 'A Kinematic Sculpure of Franks Brain as a Young Man". Apologies to the Betwaite Clan and James Joyce.

 

She's a 14' proto. Mast broke before we could get sailing fotos. Mast too stiff. Luff too round. Crunch.

 

end view- the easiest way to explain her is that she's a Proa without the little hull. wind always comes from the end of the seat to where it is fixed.

 

post-906-0-83480100-1352748117_thumb.jpg

 

reasons

 

never have to go under the sail or boom, harder to blow a tack/jibe

 

una sail setup is just too freakin' big and heavy, so why not use it to balance things rather than the opposite. you will notice the mast foot is on the lee edge

 

post-906-0-33833500-1352748527_thumb.jpg

 

my idea of leaving the mast foot on the mast track (shown), to move the sail CE, was floppy and uncontrollable. I removed it and fixed the mast foot in the middle, but still over by the lee. You'll see that in other shots.

 

a boat in balance is faster is my idea, like a windsurfer

 

mast rake can be set for conditions- rake is steering, so it's automatic. I use lines (orange lines) to move the sail laterally

 

only one foil needed, less drag. the foil moves on a track and is locked in place by water pressure laterally and longitudinally so the CR is in a more advantageous place. I kind of works. A beefier track, or multiple tracks may be better. It would also be fun to control the position of the foil longitudinally with a line- use moving the sail around as a gross control, moving the foil as a fine control.

 

post-906-0-20963900-1352749471_thumb.jpg

post-906-0-92177100-1352749506_thumb.jpg

 

It looks like pic memory is getting balky, so I'll continue in a separate post-

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The foil is a bidirectional, developed by Tom Speer. It should have the same characterisitics as a NACA 0012. Might need a trip though. Phils foils made it.

 

post-906-0-10014800-1352750146_thumb.jpg

 

I didn't have enough ceiling height to attach the mast and sails, so I added a stick in approximately the righ place, on top of the mast foot, which is red. it isn't pointing up enough, but I hope it gives the idea. The spar that is finished meets the mast/sail at the wishboom, and is attached to the seat. there is a parallel line to the spar to take the loads away from the seat. There are a lot of goosenecks on this canoe. :) The idea is to use the seat for support and take twisting loads off of the hull as much as possible. These supports are all inside the sheer lines, so I hope that's legal. ?

 

post-906-0-82952300-1352750661_thumb.jpg

 

Seat position swivels, and is controlled by the black lines, which also limit seat movement up and down. The lines can be released enough so the mast can lie on the water like a windsurfing mast, while the seat remains vertical, making it a lever to uphaul the mast. I'm using wax for the top of the seat structure. Doesn't work very well. If I do another one, Ill use the Star Boat Vang setup that Harken has. It needs minimum 24" of radius, which works with the proa setup, since you don't need the circular traveller going across the hull, so wider hulls are easy.

 

Seat positions:

 

post-906-0-99226400-1352751120_thumb.jpg

post-906-0-55213900-1352751153_thumb.jpg

post-906-0-58977600-1352751174_thumb.jpg

 

I'll move to a separate post so I don't overload things

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Last one-

 

More seat details. the one fitting outside of the sheer is the one underneath the seat outboard, which is there to keep the mast lines from falling in the water. (I know it's backwards, but I haven't got around to fixing that- another idea that didn't work...) I know knots would have more purity, but cleats are so nifty.

 

post-906-0-43372000-1352751681_thumb.jpg

post-906-0-73503700-1352751731_thumb.jpg

post-906-0-55471900-1352751704_thumb.jpg

 

and what I ultimately want to do with the seat

 

post-906-0-51107200-1352751795_thumb.jpg

 

The obligatory shot of the dog.

 

post-906-0-24804900-1352751852_thumb.jpg

 

I'm hoping my use of the seat is in the spirit of Paul Butler.

 

Anyway, I'll know more when this melts

 

post-906-0-94010900-1352751974_thumb.jpg

 

sometime in March, and I can go sailing. That is my Zen displacement tank. Pity it's out of doors.

 

So, oh wise ones, assuming it was life size, is it a legal canoe? To some extent, whether I move past this one will depend on some guidance. On the other hand, if I can develop it so it's easy to sail, I just might have that sit down windsurfer Ive been nattering on about. And then I could attach the boom support spar to the moving seat, and incline the sail over me. It is a direction the class might consider. Spirit of development and all.....

 

If any of you would like additional pics or descriptions, please ask. I might add this has all been done with wood, Titebond #, some bronze ring nails, SS and bronze scews. I think the hull weighs ~40 - 45 lbs, but my scale is ancient and suspect. Whether it's strong enough for anything but light airs?

 

Opinions please.

 

Paul

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Well Paul, If nothing else it's a work of art! I'd like to see it with the rig in place. I'm glad you're doing this so that if it doesn't work, I can cross it off my list of silly ideas to try ^_^ . I suspect that controlling the rig may be a challenge in a decent breeze.

 

I do think you need to beef up the foil support. Two tracks would be a good idea, or at least a rubbing strip lower down the hull topsides, where the bit of blue foam is (I guess you are already considering this). A sliding dagger case maybe?

 

I don't see why something like this couldn't be made to measure in as an IC. I don't think it will ever be faster than a 'real' one though because the hull is compromised to travel in both directions and you will always loose ground on tacks an gybes verses a competent 'normal' helmsman. As a proa fan myself however, I like the idea and commend your efforts. Looking forward to the video.

 

Mal.

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Hi Paul

No idea if it measures or not, but very intresting, the steering sounds like the same concept as simon had on "bootiful", a speed sailing craft of a few years back, never quite got going as it should have done but it did work, there were winches that worked on peadle power that moved the rig up and down the hulls, with just a fixed skeg at the back. Simon taught me to sail a long time ago and I helped him on this project and a few other bits and peices.

post-20243-0-38276400-1352814527_thumb.jpg

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Well Paul, If nothing else it's a work of art! I'd like to see it with the rig in place. I'm glad you're doing this so that if it doesn't work, I can cross it off my list of silly ideas to try ^_^/> . I suspect that controlling the rig may be a challenge in a decent breeze.

 

I do think you need to beef up the foil support. Two tracks would be a good idea, or at least a rubbing strip lower down the hull topsides, where the bit of blue foam is (I guess you are already considering this). A sliding dagger case maybe?

 

I don't see why something like this couldn't be made to measure in as an IC. I don't think it will ever be faster than a 'real' one though because the hull is compromised to travel in both directions and you will always loose ground on tacks an gybes verses a competent 'normal' helmsman. As a proa fan myself however, I like the idea and commend your efforts. Looking forward to the video.

 

Mal.

 

Thanks Mal, I have tossed around tacking/gybing speed, and if everything is automatic when shunting, I think I'd be in the middle of the game, given the amount to do when tacking an IC. There is a vid around starring a French RC proa shunting automatically, and it is instantaneous, so the main loss would be to the glide of a normal IC through the wind unpowered. If there is an advantage, it would be in stronger winds (?). Whether an asymmetrical section LB would be a positive? It seemed to me that a longitudinally symmetrical hull might have more planing area, a flatter run aft, a more gradual outline to the stern, and fewer handling vices. Whether these would be faster, a wash, or (horrors) one of those silly ideas (who said that?) that like a 2 iron whispers "do something glorious" awaits my determination, I suppose.

 

The problem with the foil support is how to figure the stress on the fitting to the hull. I was defining the CE of the foil at about half span, and the weight on that point at 280 lbs, which would come out at about 560 foot pounds on the traveler car which is near it's SWL, but even in 2k TW things were deforming alarmingly, which is why I glued the XPS on the side which helped a lot. How much lateral pressure are you assuming at the DB support in an IC hull? The XPS helped, but the long strip had a lot of friction on the shunt, and it's a testimony to liquid nails that the block side is still there. It's unclear to me that a protective strip on the outside of the hull would legal. A <1mm strip?

 

Oh, and the foil track(s)need(s)to be at least 2' longer.

 

Paul

 

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Hi Paul

No idea if it measures or not, but very intresting, the steering sounds like the same concept as simon had on "bootiful", a speed sailing craft of a few years back, never quite got going as it should have done but it did work, there were winches that worked on peadle power that moved the rig up and down the hulls, with just a fixed skeg at the back. Simon taught me to sail a long time ago and I helped him on this project and a few other bits and peices.

post-20243-0-38276400-1352814527_thumb.jpg

 

Bootiful is always on my mind. I have enough track to do a similar support /steering setup (with spars) but the stumbling block for me is raking the rig on the fly, given the balance challenge the seat provides. Maybe I'm too preoccupied with that. With the sliding LB, the foil can either be a centerboard or a skeg, depending on placement.

 

Did you sail on Bootiful?

 

Paul

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Shunting fast with an RC proa:

 

Check out this video on YouTube:

 

 

Not French, but James Brett design, NZ

 

Check out this video on YouTube:

 

 

 

Sent from my iPad

 

 

 

Sent from my iPad

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Quite unexpected.

 

It may run afoul of the no outriggers outside of the sheer rule.

 

The ability to get in front of another boat and apply the brakes hard could be a game changer.

 

Considering that you could drop your rig on my head will keep me on my absolute best behavior.

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Quite unexpected.

 

"It may run afoul of the no outriggers outside of the sheer rule."

 

-That one, I must admit, is a mystery wrapped in an enigma. When heeling? With the mast lying on the water?

 

"The ability to get in front of another boat and apply the brakes hard could be a game changer. "

 

-I like to think Manfred is smiling, but just a bit.

 

"Considering that you could drop your rig on my head will keep me on my absolute best behavior."

 

:)

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It's unclear to me that a protective strip on the outside of the hull would legal. A <1mm strip?

 

Paul

 

Any rubbing strips or track supports would have to satisfy the 1m transverse tape rule at the measurement station (probably at midships in the case of a shunting hull). So if you have a flat bottom, 750mm across the chines, any protrusion on the topsides would need to be at least 125mm above the chine. Not to onerous. The rubbing strip or support at each end would also have to be faired back into the hull to satisfy the planform shape rule, also not a big deal.

 

The CE of the foil will be at about 25% back from the LE, regardless of it being symmetrical fore and aft. But your biggest issue is the moment due to the span of the foil. I think you definitely need two support points. The further apart you can space the supports, the lower the loads will be, and more importantly, the less the friction will be for moving the foil fore and aft. For spacing, think in terms of the depth of a CB case or rudder pintle spacing. I really think you need two tracks to reduce the friction as much as possible. You also need to consider the stresses in a backwind situation.

 

I'm assuming that any device that runs on the tracks and supports the foil can be counted as a rudder fitting and won't contravene the rules.

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Thanks Mal, I was hoping foil track might be considered a rudder fitting, and I agree, 2 tracks are necessary. I'm wondering if 3 cars, two on top, one on bottom might be a good idea. The 4" and 11" rule is handy!

Paul

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Nah Paul, forget about the rules. I just love it when someone has the balls to build some of their ideas. Just go out and have some fun with it. I'm not sure about tacking but shunting would be quicker than some of my gybes. :P

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I'm wondering if 3 cars, two on top, one on bottom might be a good idea.

Paul

 

Yes, I think that will be necessary, otherwise it will bind up.

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Paul,

 

It would be nice to combine your sliding foil with something like my easy shunting crab claw rig

such that with a single continuous line you could slide both the rig forward and the foil aft (and vice versa) at the same time for steering.

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Paul,

 

It would be nice to combine your sliding foil with something like my easy shunting crab claw rig

such that with a single continuous line you could slide both the rig forward and the foil aft (and vice versa) at the same time for steering.

 

Mal, that is trick! I have a lot of affection for the crab claw, having spent much time with one put together by my dad. It will have to wait in line after (dare I say it?) a dipping lug (a strange obsession), and most likely a fathead something or other. Any data on VMG upwind with the claw?

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Any data on VMG upwind with the claw?

 

 

I'm not suggesting using a crab claw sail as such. The crab claw has some interesting properties, but outright efficiency is probably not one of them. Below is a photo of the model I built to test the rig. It used a fat head style sail....

 

post-3095-0-91219800-1352864949_thumb.jpg

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Wow. I can feel my brain expanding. Very Nice.

 

I really need to learn to make my own sails.

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My choice of locations for a breather hole in my hole was particularly uninspired. It's at the forward edge of the slot that my centerboard anti-gybe brake slides in. Any water at the forward edge of the cockpit can find its way in there easily. While water can get there easily I can't. What was I thinking?

 

Do I really need a breather hole?

 

If I do need one, where does it go? Given the low freeboard, I'm not sure if there is a dry location for it. Inverted orientation needs to be considered.

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Does rule 4g (2 holes only breaching the hull) preclude a hole for an unstayed mast?

 

Or breathing holes now that crapitano mentions it.......

 

Paul

 

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If I do need one, where does it go?

You do need something. Boats taken from cold water to hot sunshine change temperature a lot. Just above deck level in the front bulkhead ought to work. On my boat the breather is into the mast stump from inside the foredeck, and then out through the base next to the deck. I reckon that just above dance floor level on the back of the foredeck is pretty much never immersed.

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Breather holes are nice.

A little Goretex over a hole is a pretty elegant solution for letting air in and out but stopping actual water. Find an old garment on itis way out and steal a bit.

Another solution is to locate the hole high in the bulkhead but put a tube on the inside that goes all the way down to the keel. This way one end is always above the waterline.

SHC

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Does the foredeck in plan view need to be curved, or can it look like an inverted V?

 

can the unstayed mast partners be the top of an an exposed tripod, or quadpod? Straight or curved?

 

Or does that violate the no holes all the way through rule?

 

If you find yourself asking why, the answer is Starling Burgess. Kind of.

 

Well, that and the mast base of Paul Bieker's 'Rocket Science'....

 

Without windows.

 

Paul

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The deck profile must be a continuous line, convex, concave or straight sections are OK with limiting radii at junctions, and only one concave section per side of a limited amount.

The Maas boat I'm building is pretty much - from the stem - straight, small hollow just in front of the shrouds, long straight section for the seat track, and short curvy bit to the aft pointy end.

Holes can't go through the hull ( apart from board and rudder ), so a mast-gate hole is OK.

Read the rules for the details ;-)

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Thanks for the specific context, Andy.

 

Every time I look at the rules, I seem get something different, so I need perspective like yours.

 

Thanks,

 

Paul

 

 

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Hi Paul

No idea if it measures or not, but very intresting, the steering sounds like the same concept as simon had on "bootiful", a speed sailing craft of a few years back, never quite got going as it should have done but it did work, there were winches that worked on peadle power that moved the rig up and down the hulls, with just a fixed skeg at the back. Simon taught me to sail a long time ago and I helped him on this project and a few other bits and peices.

post-20243-0-38276400-1352814527_thumb.jpg

 

Bootiful is always on my mind. I have enough track to do a similar support /steering setup (with spars) but the stumbling block for me is raking the rig on the fly, given the balance challenge the seat provides. Maybe I'm too preoccupied with that. With the sliding LB, the foil can either be a centerboard or a skeg, depending on placement.

 

Did you sail on Bootiful?

 

Paul

Hi Paul

No, never had a chance, help launch her a few times, it all worked but was a bit fragile, took a lot of getting in the water and the conditions were not right for too much of the time (tide/ wind direction/ wind strength) and so the funding faded away. However nice place to sit and wait for that window (Brancaster Beach)!

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I'm reading the rules ... every other lines, and I don't see a ban on trapeze. Did I miss something?

Could one use a trap wire as an assistance for hiking? Hell, could one trap out of the end of the plank?

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Anders tried that; I think he donated the boat to charity though.

 

What? Trapping + plank?

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I'm reading the rules ... every other lines, and I don't see a ban on trapeze.

RRS bans trapezes - unless specifically permitted - so there's no need for class rules to do so.

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I guess there's nothing about trapezes, nothing that I could see with my quick read through, other than the width of the plank rule. I guess you could have a fixed sideways plank and trapeze off the 500mm wide tip but I'd think that's harder than just using the plank as designed.

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I'm reading the rules ... every other lines, and I don't see a ban on trapeze.

RRS bans trapezes - unless specifically permitted - so there's no need for class rules to do so.

 

Arf, I see. Thanks.

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Hi Jim, we just posted at the same time.

 

Are we bound by the RRS, as we fall under the umbrella if the ICA not ISAF?

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I'm reading the rules ... every other lines, and I don't see a ban on trapeze.

RRS bans trapezes - unless specifically permitted - so there's no need for class rules to do so.

 

What rule would that be? Can't find it on the rrs ...

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