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      Abbreviated rules   07/28/2017

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Doug

 

Thanks for your reply. You seem to fall into the same "dumb" trap that you say I fell into. You use 2 stills from a video as evidence of performance. Let's be very clear on this. A few moments of stable flight the best of which is a 16 second 'flight" does not equal proof of anything, other than maybe potential for the system to work. In the same way as you have taken fleeting moments as evidence, i could take others in the video as proof the system is flawed. Yet the truth is that it is far too early in the development to make either claim. You might well consider the test sail to be a success, as I might as well, but on the basis that the boat didn't break and there were fleeting moments of promise. However, as everybody has tried to point out to you, there is not enough evidence of anything to make any real claims.

 

As to your comments, you seem to ignore the core question and instead of answering it, try to claim that you have proved it works so you don't need to say any more. As part of your answer you have added information that made the original question even more relevant. I will repeat the question, so try answering it.

 

The key component for up-tip foils to work is leeway. Your boat has a central centreboard (with T foil on the bottom). There is no getting away from the fact that it will reduce leeway. Now you tell us that the foil also produces lift to windward, which further reduces leeway. So I will ask you again. With leeway dramatically reduced or maybe even eliminated, how is the up-tip foil going to work? Based on the videos you have posted, it could be said that the little bit of steady state flight is achieved when conditions are consistent and that there is no evidence that steady state is achieved when the boat either speeds up or decelerates. So as we will not agree on what the video shows, how about you explain why the up-tip will work with little to no leeway.

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No - do not explain; just post an unedited constant video of the boat in action.

Let the actions of the boat show the audience how successful it is.

Or is that too complex a concept to grasp?

 

15 seconds of flight in 12 months does not equal "100% successful" in anyone's comprehension.

 

Beer & Chips on standby.

 

I predict many months of unsuitable weather about to strike Florida; you have been warned holidaymakers.

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You write "You have to be really off to say that the rock steady foiling in that last video means nothing."

You probably need to watch the video again, and in the presence of another person who is not invested in your mental well being at that time, to get some reasonable input as to what the video does show......

The video does not show rock steady anything - it shows a boat - which when temporarily in flight, lurches from leeward to windward float.
There is as much footage in that video of plant foliage, as there is footage of foiling.

You also opened with "Again, you don't seem to understand: the vertical portion of the ama foil is at +3 degrees AOI. The vertical portion of the daggerboard is at zero degrees. So the ama foil is always developing lift to windward(to resist leeway) and allow leeway coupling with the uptip portion of the foil particularly upwind."

This is quite disturbing that you fail to understand that any foil that is set with 0 angle of attack (relative to the hull centreline) is incapable of providing lift that will contribute to leeway resistance. You have just written off nearly every sailboat afloat with traditional daggerboard, centreboard or fin keel.

 

Your writing on this forum only ever serve to make your claims ever more incredulous, and sink your reputation further.

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All,

 

It is painfully obvious that Doug Lord suffers from severe Narcisistic Personality Disorder (NPD). People with NPD commonly live in a world of delusion. Any attempt to try and reason with them is futile, as NPD is a mental illness.

 

http://samvak.tripod.com/narcissistpsychotic.html

 

-One of the most important symptoms of pathological narcissism (the Narcissistic Personality Disorder) is grandiosity. Grandiose fantasies (megalomaniac delusions of grandeur) permeate every aspect of the narcissist's personality. They are the reason that the narcissist feels entitled to special treatment which is typically incommensurate with his real accomplishments. The Grandiosity Gap is the abyss between the narcissist's self-image (as reified by his False Self) and reality.

 

-A delusion is "a false belief based on incorrect inference about external reality that is firmly sustained despite what almost everyone else believes and despite what constitutes incontrovertible and obvious proof or evidence to the contrary".

 

***R. T.***

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Doug - why a year?

Did you rebuild it from the ground up, due to the hip-hip-hippity hop-hop-hoppity sailing performance?

Are you launching the exact same boat?

What's the story?

 

Release the bunny!

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doug, you compare yours with the present top designs

 

all of them spend months, with tens of hours in the water and several versions of hardware, and still claim that they have a product, but will still be refined

 

how can you honestly claim yours is proven, 100% successfull, etc, with ONLY A COUPLE OF SAILS, with a tiny fraction of development time, on and off the water, as whole world top professional teams????

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ahh, good point.

 

I think the test plan was get it wet, and get it back to shore.

 

I'm guessing the thing self-destructed and had to be re-built, hence the 1 year time between sails...

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doug, you compare yours with the present top designs

 

all of them spend months, with tens of hours in the water and several versions of hardware, and still claim that they have a product, but will still be refined

 

how can you honestly claim yours is proven, 100% successfull, etc, with ONLY A COUPLE OF SAILS, with a tiny fraction of development time, on and off the water, as whole world top professional teams????

You should try reading-thats bullshit! The foils worked 100% perfectly but there is still plenty of refining and testing to do as I've said a hundred times. And there has been FOUR YEARS + of design and development time. The design and development thread from the begining to now: http://www.boatdesign.net/forums/multihulls/high-performance-mpx-foil-self-righting-trimaran-test-model-36058-136.html

 

"The testing clearly shows the progression of the boat to full foiling from the problems encountered at the beginning-the last video is 100% proof that the foil system worked perfectly-regardless of any uninformed attempt to say otherwise. But testing is not done yet even though we reached a major milestone with the boat foiling in a 5 mph wind while using two different altitude control systems simultaneously. Hopefully, starting in June we'll get a lot more video and in stronger wind. But July 24th, 2014 was a major accomplishment for the boat after a great deal of development-and we will build on that this year."

============

 

"Simon, you're so off base-my Fire Arrow test model tri uses one ama UptiP foil at a time and one wand controlled main foil with a rudder T-foil. The cool thing about the Fire Arrow foil configuration is that it uses two foils with different altitude control systems at the same time-for the first time on any size multihull anywhere at any time. It is a truly revolutionary foil configuration that has tremendous potential from 12 footer's to 100+ foot trimarans. It has the potential to completely revolutionize the design and performance of under 20' trimarans.

Ians surface piercing RC foilers are tremendous and fit into the Mini 40 class of racing tri's at around 6lbs-7lbs each. The Fire Arrow, on the other hand, is a heavy, nearly exact scale, test model of a 19.5 footer at 21.13lbs. Oh, and it flies in a 5mph breeze just exactly like the full size version will.

Looks like Fire Arrow testing will resume on or about June 2 weather permitting..........."

=============

" your "criticism" of my test model and foil development work is incredibly pathetic without any "scientific" basis at all-just a compendium of nonsense reflecting your feeling that if I say it or do it it must be wrong. I have designed and continue to develop my own "automatic" UptiP foil that requires no adjustment whatsoever while sailing from low speed takeoff on up-and I have the pictures and video to prove it. This last video was the very first time the boat flew and everything regarding the foils worked perfectly especially the fact that the boat took off in a 5mph(4.34knot) wind. The two pictures below, "A" and "B" clearly show that the ama UptiP foil is maintaining the same altitude in two different load cases and at two different speeds. You simply can't get better than that-except to refine them while maintaining their high level of performance. That's what the test model program is about now that we've proved the foils."

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Doug, we can see you watching the board.

 

Does it really take 3+ days to craft a response?

Why 1+ years between sails?

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doug, you compare yours with the present top designs

 

all of them spend months, with tens of hours in the water and several versions of hardware, and still claim that they have a product, but will still be refined

 

how can you honestly claim yours is proven, 100% successfull, etc, with ONLY A COUPLE OF SAILS, with a tiny fraction of development time, on and off the water, as whole world top professional teams????

You should try reading-thats bullshit! The foils worked 100% perfectly but there is still plenty of refining and testing to do as I've said a hundred times. And there has been FOUR YEARS + of design and development time. The design and development thread from the begining to now: http://www.boatdesign.net/forums/multihulls/high-performance-mpx-foil-self-righting-trimaran-test-model-36058-136.html

 

"The testing clearly shows the progression of the boat to full foiling from the problems encountered at the beginning-the last video is 100% proof that the foil system worked perfectly-regardless of any .....

 

etc etc

 

doug, no doubt you put a lot of thought and work. the problem is with the claims. There can be no claims until after the ON THE WATER development. you just started on the water testing, you´re sorting other systems, look at the the other guys... hours and hours on the water, changing things, trying again...

 

D4Z is gorgeous, by the way. I hope it becomes a foiling boat

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It took four years because 3 years and 11 months were spent posting on forums !

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"The foils worked 100% perfectly but there is still plenty of refining and testing to do"

 

.....isnt there a small contradiction in that sentence above?

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It's not a small contradiction at all.

It's freaking huge.

If the contradiction was scaled up into full sized testing, it would be the Galloping Gertie of all hydro foil attempts.

 

 

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Unfortunately, DL with his predilection for wacky names, has missed the boat for "iFoil"

Not only has someone had the audacity to steal the name ( DL has iFlap, uCrap etc etc)

BUT they also have a product that works........

Cheeky Bastards

http://www.ifoil.co.uk/

 

Check it out. I have no association to them.

 

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Thats pretty interesting! Especially the 14 seconds of live action......Looks like they're using Jon Howes' patented surface running foil-which was a major technical hydrofoil advance 5 or so years ago and still is now. Originally used on the Tomahawk monofoiler(see below).

How Jons foil works: http://www.ifoil.co.uk/public/files/how-it-works.pdf

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Very interesting comments by John Casey sailing(foiling) in the Florida 300. Most people will remember the uninformed anti-foilers comments on how weeds would just kill any hydrofoil-even though it was pointed out the vertical daggerboards could also be a problem. Now read this from the front page:

 

"The real story of our day came courtesy of large clumps of sargasso lining up on their march to shore, just hanging out waiting for us. Yes, they play havoc with our daggerboard boats, but a unique and surprising thing happens when the FCS foils through the weeds; they slice right though them. What we thought was going to be the biggest hindrance on this flat water leg from Islamorada to Key Biscayne was actually helpful to us, as the slower boats had to clear their boards far more often. We called our day ‘mowing the lawn’."

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Thank you Boink,

 

That's interesting and could trigger interesting discussions too.

There's a point I miss with this kind of foil, I though these anti-cavitation sections were relevant for speeds >50 knts?

 

It seems that they are also used for height control/ lift management purposes.

 

Regards

W

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W, Jons surface running foil is not like a supercavitating foil at all. The point of it is to run effectively on the surface, rather that fully submerged. If you haven't allready, read the "how it works link" in post 130.

 

Pictures-supercavitating foil(Hydrofoils Inc) and Howes surface running foil(from Jon Howes):

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This conversation is all very good for gettign the boat out of the water, but that results simply in boats that jump out of the water and crash.

 

The long view requires that we have a self regulating system beyond wands that maintain level flight in the face of pitch and roll dynamics. part of that is solved with dynamic rigs (ala Bethwaite) and control systems that are self regulating.

 

that's where I think we need to go.

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Howes foil is designed as a self regulating surface running foil "that maintains level flight in the face of pitch and roll dynamics"-thats why it is such a significant invention.

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Doug for crying out loud, iFoils and Tomahawk are one and the same.

 

If the link to iFoils is posted - there is no need to link back to the same site - nor cut and paste large sections of related material. We can all operate a keyboard as well as you can.

 

What we have seen in the last few weeks are alternative solutions to L shaped uptip foils.

 

I have written at length in the past, how F1 cars have evolved from the clumsy almost biplane-esq solutions of introducing wings to their cars in the early 70's to the highly sculpted and refined solutions that are created today - and this will mirror how hydrofoils will develop in the sailing world.

 

We have gone from Ladder foils on Williwaw which may have lifted the hull out, but barely increased velocity, through Hyroptere style tripods & Moth T-foils to AC derived catamarans with L-shaped foils.

 

Some go with 2, some with 3 and others with 4 foils in; and then you have active control versus passive.

 

All are driven by their projects needs and wants. Some are dictated by class rules that actively discourage hydrofoils. Others are completely blue-sky designs.

 

The point that I am, and have been trying to make for some time, is that all have their merits - but you can be sure that solutions will progress towards higher aspect, thinner sections, with lower overall drag for given lift, allowing faster speeds and smoother transitions, as materials develop and knowledge increases.

 

It is no coincidence that the brightest minds in this field are from aerospace fields, either design or construction. Look how wing sections on gliders have evolved in the last 30 or years, and military aircraft as well, which are now using such unstable foil sections as to require computer intervention to maintain flight, but which can now operate in speed ranges only previously held by some niche designs, whilst still being manoeuvrable enough to be considered a jet fighter.

 

So anyone who hangs their hat on one style and says that "that's it", is in my mind foolish and naïve. Doug prove us all wrong, by all means, but if you continue to treat everyone here as retarded, with your spoon feeding of other peoples work; whilst your own creations get 3 or 4 outings every 12 months, achieving hip hop results of 15 seconds of sustained flight, and then claim 100% success, you will fail to earn my respect, and I suspect 90% of the other readership as well.

 

Carry on everyone else - just needed to vent......

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This conversation is all very good for gettign the boat out of the water, but that results simply in boats that jump out of the water and crash.

 

The long view requires that we have a self regulating system beyond wands that maintain level flight in the face of pitch and roll dynamics. part of that is solved with dynamic rigs (ala Bethwaite) and control systems that are self regulating.

 

that's where I think we need to go.

It is probably lost within all the BS that Doug is spouting about his 100% successful toy, but most of the foils we are talking about do not result in the boats jumping out of the water and crashing. Depending on the type of boat and how much it needs to avoid any crashes, this is either totally automatic or it works in conjunction with crew actions. So with the up=tip foils that we see on the GC32 (up-tip foil), there is little to no jumping out. When you get to the size of the Flying Phantom (up-tip foil), it seems that you need some sailor input (helm and sheeting) in order to get the best ride while when you get to the A Class (J and Z foils), stable flight is possible but you need to steer, sheet and move your weight accordingly. Others have used different systems with "active" ride height control.

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I used this technique to build the experimental(and now proven) UptiP foils for the Fire Arrow and will use the same basic concept to build full size versions of the same foils.

I was lucky to have an Architectural Foam Company nearby and and went in and introduced myself to the owner and told her what I needed and showed her the plan. She said no problem and and cut the molds using a computer controlled hot wire. After I got the basic female mold parts out of 2 lb styro(XPS, I think) I laid out the planform of the foils on the the foam and then created the section shape by hand and then covered it with .03125" sheet wax. I used a top and bottom jig to create an accurate section shape.

Lay up was carbon with a microsphere core-both half's done at the same time so that after 8 hours I had an excellent foil requiring a minimum of finish work.

Inexpensive, quick and a good way to build experimental UptiP foils-of almost any size-certainly for boats 2' up to 20+' in a hurry.

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Finished foils attached to amas:

 

pix-center=original foils; left and right =same foils with modified planform.

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So what.........?

 

Still no proof of anything.......

 

There's literally hundreds of hours of footage of hydro-foiling everything to be found on the internet - yet you haven't got more than a few minutes of your own footage, which has nothing more than a few seconds of flight at a time.

Way to go.

 

You are now showing pictures of foils getting bigger and bigger with each of your design evolutions.

 

Well guess what Douglas, if you continue to make the foils bigger and bigger, (which is completely the opposite design direction being taken by every other developer of new foils), eventually your creations will float from their static buoyancy alone...... no need for any forward motion at all.

 

And you will have created the "world's first" levitating sailboat - NOT!

 

Save yourself the aggro and just strap a few child's floaties on chop sticks under your latest creation - if you can spare them that is.......

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Let's take a hard look at Dougie's "two-stage ama" thing-a-ma-jig, shall we?

 

I'm amused by the claims he makes regarding this wild and wooley healing resistance form that is pretty much the cat's ass of high drag structures. When you really take a look at how this thing is going to immerse under healing moment loads, it will create so much drag through the water that the slowing boat will solve its own issues with preventing pitch-poling... simply because the boat will be at, or near, a dead stop and the pitch-pole effect will not be in play. Now, of course, that won't free the bad little critter from capsizing, but The Dougenstein hasn't bothered to address that comfy bit of negativity in the design loop.

 

I can see the main hull foils lifting the center of the boat, the ama foil being rendered ineffective, the upstairs part of the wonderful Two-stage thingy digging-in where the tramp surfaces and the sail are doing the rest of the work, sending this paraplegic water spider into a loop.

 

Hippity-hoppity and over it goes. I predict this will happen when Doug ever gets the toy out in stiffer wind conditions than the 2 knots of breeze he has poked around in so far. He will blame it on the controls getting stuck, or that the wreck of a secret Spanish galleon grabbed one of the foils and tripped the boat physically, but it will never be about faulty, goofball design. Nahhh, that's just too hard on the ego.

 

I'm just wondering why Nigel, or VPLP, haven't installed these huge, aero-draggy second stage forms on any of their super high-end, ocean going beasts. They just make so much sense.

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Let's take a hard look at Dougie's "two-stage ama" thing-a-ma-jig, shall we?

 

 

Let's not.

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Doug

 

Next time you want to make foils, rather than use such a long winded and potentially inaccurate method (due to hand shaping) try 3D printing. While you could 3D print the mold, I would probably 3D print the foil as a plug although i believe that you could probably 3D print the finished items of you choose the right material. 3D printing as a rapid development tool is just great and if you are doing enough, machines really aren't very expensive.

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That's a great idea; one of many that were suggested to Doug when he did his great styrofoam foray.

 

Trouble is... Doug does not have any skills in 3D design, doesn't have the required software to create the files and instead of getting up to speed with the design industry, finds it more important to buy spendy carbon parts than to join the workflow realities of a modern design shop?

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Doug

 

Next time you want to make foils, rather than use such a long winded and potentially inaccurate method (due to hand shaping) try 3D printing. While you could 3D print the mold, I would probably 3D print the foil as a plug although i believe that you could probably 3D print the finished items of you choose the right material. 3D printing as a rapid development tool is just great and if you are doing enough, machines really aren't very expensive.

 

There are some comments here regarding using a printer to make relatively small RC model foils: http://www.rcgroups.com/forums/showthread.php?t=2384452&page=6

The technique I described above is inexpensive, fast and as accurate as you want it to be. It's simply bullshit to say there is a problem with accuracy using this technique. It allows experimental foils of almost any size to be built and tested with a small investment in time and money.

 

Picture 1 below by Pierre Orphanidis/www.vsail.info--Shows a Luna Rosa mainfoil being hand finished to great accuracy using jigs for the sections, Pictures 2-4 show hand made all carbon experimental foils using a similar quick-build technique:

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Total false equivalency with the photo of the guys who are surface fairing a large foil.

 

Where you butchered the baseline shape with your wacky hand job technique, they had a multi-axis CNC router to create the form. When they were surface fairing an accurate section and planform, you were still building a shape with bog that was shit from the beginning.

 

You have no business likening your backyard baloney to what is going on here in the photo. It's like telling everyone you went to Mars when what you really did was stand in front of a Mars diorama at a space museum wearing a tin foil shirt.

 

If you really want to know why your boat behaves like bad puppy with a pissing problem, the foils would be exhibit A in the chase.

 

It does make for good comedy, though.

 

.

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Doug

 

Next time you want to make foils, rather than use such a long winded and potentially inaccurate method (due to hand shaping) try 3D printing. While you could 3D print the mold, I would probably 3D print the foil as a plug although i believe that you could probably 3D print the finished items of you choose the right material. 3D printing as a rapid development tool is just great and if you are doing enough, machines really aren't very expensive.

 

There are some comments here regarding using a printer to make relatively small RC model foils: http://www.rcgroups.com/forums/showthread.php?t=2384452&page=6

The technique I described above is inexpensive, fast and as accurate as you want it to be. It's simply bullshit to say there is a problem with accuracy using this technique. It allows experimental foils of almost any size to be built and tested with a small investment in time and money.

 

Doug

 

You really need to learn to read and to evaluate information better. I made a suggestion in the spirit of being helpful and as usual, all you do is attack.

 

First, i pointed out that hand shaping of concave molds has the POTENTIAL for inaccuracy. To try to suggest that it doesn't is stupid. Next, i did follow your link and found that those who are knowledgeable about 3D printing recommended it, while those would only had experience of older style or domestic quality printers. Go back and read what Jim (RCMM) wrote. I can also confirm from personal experience that you can successfully 3d print components such as your foils. It would be quick, very accurate and if you find the right place, cost effective. Of course, you need to be able to prepare the right CAD files but I have to assume that you can, because it is the basic skill needed to design the foils you are making. Without CAD and associated analytically tools, your foils will simply be a mix of guesswork and wishful thinking and from everything you have been telling us, your foils are highly developed. In fact, it would be really interesting to see some of the data and analysis on the foils you picture above, although my guess is that you will say that information is secret.

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Printing may be cost effective for production RC foils down the line-and, if so, would help grow the AC 4.8RC wannabe class. But it is not cost effective for one off experimental RC foils compared to the technique above-so far.

You're funny ,Simon-speaking of "read and to evaluate information better": did you even read what Jim wrote?! He suggested using stereolithography with titanium. And even then the surface would have to be hand finished.

Jim said:

Doug,
It depends what type of printer you use. In polymer you won't get anything close to the strength of carbon/epoxy, but stereolithography gives a pretty stiff material with a smooth surface. You will get a very strong part if you use selective laser sintering and make the part from titanium, but the surface is a bit rough and will need to be finished. As for cost, I've never had to pay a commercial price, but I think that you might be surprised. The technology is developing very fast and commercial firms are becoming more common.
Jim.

 

 

from wikipedia:

 

Although stereolithography can produce a wide variety of shapes, it has often been expensive; the cost of photo-curable resin has long ranged from $80 to $210 per liter, and the cost of stereolithography machines has ranged from $100,000 to more than $500,000.

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Doug

 

Don't believe everything you read on Wiki. For starters, steriolithography is considered by everybody I know to be 3D printing. And you can get small machines for under $4000. Big machines do cost a fair amount but a friend has a large pro machine that cost a fraction of the figures you see on Wiki.

 

And well done finding somebody who prints carbon. There are lots of them about. The best for cost/quality/convenience can be found operating over the net and out of China, with a turn around of 5 days. China is really beginning to lead the way. They even built houses by 3D printing them.

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Doug - you don't buy the machine. You farm out the fabrication to a shop. I bet you're in for a hundred bucks.

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Stereolithography and Laser Sintering are two very different processes. One cannot produce metal parts with stereolithography. One cannot produce Titanium parts with stereolithography.

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Doug doesn't actually know these things, guys, He looks this stuff up on Google and spews it back to the unsuspecting as knowledge. With all the time that it took to produce his non-functional trimaran model, he could have purchased a seat of Rhino, learned how to use it and actually be able to produce files that could go directly to a 3D printer for accurate testing. Mr. Lord, however, would rather stick on cutesy arrow graphics and load-up his design concepts with too many complex systems.

 

Hyperbole is always more important than substance. Actually, that's a design credo that is pinned on the wall in Doug's shop/dining room.

 

Why do things right when you can slam it together now and then obliquely bitch about it later?

 

.

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See, there's the Internet expert, now.

 

Can't get out of his own car without help, but he's a self-appointed Master of the Googlism.

 

Doug is an absolute treasure trove of ideas for a script writer.

.

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Douglas.... if you get off your butt and enroll in a few drafting, or 3D design classes at the local Junior College, you can buy the Rhino package for peanuts with your student I.D.

 

Spend the next few months learning the program from the hundreds of tutorials available for free all over the Web and stop being such a low brow procrastinator about actually joining the world of boat design.

 

Nothing to stop you but your own fear of the discipline involved to actually step-up and get with the program.

 

.

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Doug - I've cracked it - your schoolboy error was to:

"I laid out the planform of the foils on the the foam and then created the section shape by hand and then covered it with .03125 sheet wax." (DL post #139)

 

I did a quick bit of QC (that's quality control - oh, sorry I forgot - you are a past master at series production runs......) and I have found that, inadvertently I am sure, you have used Shit Wax and in some parts it was 0.03124" and in other parts it was 0.03126" thick.

 

Oh, the ignominy.....

 

Still it's another fall back excuse for delaying the "100%" successful foiling announcement.

Try to get more footage of sailboat and less of the shore side foliage this time.

 

I confess, I have had to re-stock my beer and snack stock - it was getting close to its use by date - your costing me man. Chop, freaking Chop.

Fresh supplies have been procured - with extra long use by date. So let's get this circus underway.......

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Fire Arrow Test Model Foil Configuration

 

One of the great advantages of using a properly designed UptiP foil on a foiling trimaran ama is SIMPLICITY: on the Fire Arrow the ama foil has NEVER needed to have the angle of incidence adjusted while sailing as is common on many UptiP foil applications. And if the foil is properly designed for it's application ,it's efficiency will be apparent. As shown in the pictures below the lee ama flies before the main hull, but as soon as the boat speeds up and the main hull flies the lee ama altitude remains the same. That illustrates that the lee UptiP foil is working PERFECTLY in two different load and speed cases. See pix "A" and "B" below.

The Fire Arrow uses a wand controlled main foil which controls the altitude of the main hull and the angle of heel of the whole boat. Further, and this is very important: the wand controlled main foil works with the single rudder T-foil in a bi-foiler arrangement and the two together control the ride angle of the lee ama UptiP foil. That prevents pitch excursions caused solely by the lee ama foil.
The way the mainfoil works is that as soon as the main hull flies the mainfoil begins to unload with the lee ama foil gradually taking the majority of load. That allows the mainfoil to work with the rudder T -foil to control the pitch of the boat with far more pitch authority than on a conventional tri. And, using a wand controlled(or similar) foil on the daggerboard allows the main hull to fly MUCH SOONER than it would if it had to wait for wind pressure to do it.
The mainfoil can also develop substantial downforce* increasing the righting moment in response to gusts. All this is done 100% automatically making for a simple, robust system that requires ZERO crew attention!
* with downforce, the main foil works similarly to a Moth foil with Veal Heel, generating a component of lift to windward.See illustration below.
-------
I'm getting ready to test a new type of surface piercing T-foil that may work as well as a wand controlled foil-only simpler. If the tests on the D4Z pan out then a version of the foil will be tested on the Fire Arrow as a direct replacement for the wand controlled main foil.
The vertical portion of the ama foil is at +3 degrees AOI. The vertical portion of the daggerboard is at zero degrees. So the UptiP ama foil is developing lift to windward to allow leeway coupling and develop lateral resistance for the boat particularly upwind.
In stronger conditions, when the main foil develops down force( upwind), the leeway components are greater than the vertical portion of the UptiP foil can effectively handle, there is a small extra component of lift to windward(due to downforce)-while the vertical portion of the ama foil is still working at 100%. The daggerboard is designed to be unloaded by the lee ama foil to reduce drag and facilitate leeway coupling.
However, it should be pointed out that the ama foil will still provide substantial vertical lift with little to no leeway coupling-like can occur off the wind. Lift substantially(and automatically) increases upwind because of leeway coupling.
----
Testing clearly shows the progression of the boat to full foiling from the problems encountered at the beginning-the last video is 100% proof that the foil system worked perfectly-regardless of any uninformed attempt to say otherwise. But testing is not done yet even though we reached a major milestone with the boat foiling in a 5 mph wind while using two different altitude control systems simultaneously. Hopefully, starting in June we'll get a lot more video and in stronger wind. But July 24th, 2014 was a major accomplishment for the boat after a great deal of development-and we will build on that this year.
Pictures "A" and "B" below clearly show the lee ama UptiP foil controlling altitude in two different speed and load cases- a clear demonstration of the value of an UptiP foil used in a trimaran configuration.
Attributes of the Fire Arrow foil configuration:
1) allows an oversquare trimaran to foil in very light air,
--
2) allows full foiling upwind and downwind completely automatically without any adjustments by the crew,
--
3) allows for retractable foils controlled from the cockpit,
--
4) allows the lee UptiP ama foil, with an AOI of +3 degrees, to unload the daggerboard(AOI zero degrees) for reduced drag and enhanced leeway coupling.
--
5) the foil system has considerably greater pitch authority than any conventional trimaran,
--
6) allows automatic control of the angle of heel of the whole boat,
--
7) allows automatic control of the ride angle of the lee ama UptiP foil.
--
8) allows mainfoil to automatically unload as the mainhull flies ,dramatically reducing drag.
--
9) allows automatic gust response with instantaneous increases in righting moment (automatically) as required.
--
10) allows a "Two Stage" ama that provides back up buoyancy if needed but allows the part of the ama that would normally make incidental contact with the water, to be as small as practical.(see pix below).
Final video(short version) of 2014 Testing showing full foiling. See full length version showing "glimpses" of the boat foiling upwind.

post-30-0-85010200-1432575394_thumb.jpg

post-30-0-18412800-1432575474_thumb.jpg

post-30-0-77453000-1432575503_thumb.jpg

post-30-0-42850100-1432575537_thumb.jpg

post-30-0-16843400-1432575761_thumb.jpg

post-30-0-57660600-1432575888_thumb.jpg

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A Class Cat Foils---comments by Dario Valenza: http://carbonicboats.blogspot.com/

 

Declaration of Independence

North American A Class sailors recently voted to Remove Rule 8 as a constraint during their events.

With my apologies for editing one of the most important texts in history, here is a tongue-in-cheek look at why the move was necessary and successful:

We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Foiling.
That to secure these rights, Technical Committees are instituted among Men, deriving their just powers from the consent of the governed.
That whenever any Form of Measures Guidelines becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles, as to them shall seem most likely to effect their Safety and Happiness.
When a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, it is their right, it is their duty, to throw off such Government, and to provide new Guards for their Boatspeed and Stability.
Such has been the patient sufferance of these A Class Sailors; and such is now the necessity which constrains them to alter their former Systems of Government.

I have previously stated that the current Rule, if interpreted consistently, though not perfect, allowed sufficient freedom to keep developing in the historical spirit of the A Class, and remain relevant as the foremost big fleet development beach cat.
However, for reasons that may be genuine or self interested, a small vocal group has insisted on applying what they view as 'the spirit of the rule' as they claim was intended.
The result has been inconsistency, uncertainty, and growing anachronism, as other classes, one-designs, and now even cruising boats pursue the sensible path. While the A struggles with elaborate, inefficient and dangerous rule cheats.

A Few Examples

'AND' does not equal 'OR'.
This hardly needs explaining. Consider the following sentences taken from established jurisprudence:
- Men over 30 and single shall receive admission.
- Men over 30 or single shall receive admission.
Plainly the latter entitles men under 30 to receive admission whilst the former does not.
Read Rule 8.2 and draw your own conclusion.

'All positions' cannot include what happens before or after racing (as defined by ISAF).
When we come back to the beach, we remove our straight, curved, or bent foils, and rest them on the trampoline. Often we place them so they overhang the side of the boat.
Similarly, we lower our sail right past the lower limit band.
For that matter, we often lower the mast by pivoting it forward so it grossly exceeds maximum overall length.
All such actions would not be permitted during racing, the only time when our equipment must be rule compliant.
In order to indicate limits to permitted positions, contrasting bands are painted on.
Though equipment can travel past such bands (a subset of 'all' positions), our honour (and the possibility of others seeing us) keeps us compliant.
This is accepted even for 'newfangled' L and T dagger rudders, where full retraction breaches Rule 3.
Standard practice applied throughout: If you don't do it during a race, it is fine.
But foils are somehow held to a different standard because, in the minds of some, arbitrarily perceived intent trumps consistency and an expectation of objectivity.

Interlinked appendages (such as two rudders connected by a crossbar), both reacting to forces exerted by wind and water, are accepted and common. Join the dots...

Going Forward

Enough said on the way Rule 8 was stretched and tortured.
Removing it makes sense for two principal reasons.

1) It is the only 'non-dimensional' rule in a Class that is otherwise governed by 'boxes'.
Limiting length, beam, mass, sail area, and other key parametres keeps absolute performance close among different designs, but allows experimentation with novel configurations. All within clear dimensional limits.

2) Freeing up how foils may be mounted makes it much cheaper and easier to upgrade an older boat to close the gap with newer ones.

Reiterating Our Conclusion

I believe manufacturers should cater to market demand rather than agitate for rule changes.
There should be an expectation of consistency in the application of a published and valid rule so that all who invest time and money in our great sport can do so on a level playing field.
When things become plainly untenable, then we should support change.

The message is a positive one: Get out there and develop. Things are looking up.
To abuse another great historical statement:
This is the end of the beginning!

post-30-0-31451500-1432579108_thumb.jpg

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Fire Arrow Test Model Foil Configuration

 

One of the great advantages of using a properly designed UptiP foil on a foiling trimaran ama is SIMPLICITY: on the Fire Arrow the ama foil has NEVER needed to have the angle of incidence adjusted while sailing as is common on many UptiP foil applications. And if the foil is properly designed for it's application ,it's efficiency will be apparent. As shown in the pictures below the lee ama flies before the main hull, but as soon as the boat speeds up and the main hull flies the lee ama altitude remains the same. That illustrates that the lee UptiP foil is working PERFECTLY in two different load and speed cases. See pix "A" and "B" below.

The Fire Arrow uses a wand controlled main foil which controls the altitude of the main hull and the angle of heel of the whole boat. Further, and this is very important: the wand controlled main foil works with the single rudder T-foil in a bi-foiler arrangement and the two together control the ride angle of the lee ama UptiP foil. That prevents pitch excursions caused solely by the lee ama foil.
The way the mainfoil works is that as soon as the main hull flies the mainfoil begins to unload with the lee ama foil gradually taking the majority of load. That allows the mainfoil to work with the rudder T -foil to control the pitch of the boat with far more pitch authority than on a conventional tri. And, using a wand controlled(or similar) foil on the daggerboard allows the main hull to fly MUCH SOONER than it would if it had to wait for wind pressure to do it.
The mainfoil can also develop substantial downforce* increasing the righting moment in response to gusts. All this is done 100% automatically making for a simple, robust system that requires ZERO crew attention!
* with downforce, the main foil works similarly to a Moth foil with Veal Heel, generating a component of lift to windward.See illustration below.
-------
I'm getting ready to test a new type of surface piercing T-foil that may work as well as a wand controlled foil-only simpler. If the tests on the D4Z pan out then a version of the foil will be tested on the Fire Arrow as a direct replacement for the wand controlled main foil.
The vertical portion of the ama foil is at +3 degrees AOI. The vertical portion of the daggerboard is at zero degrees. So the UptiP ama foil is developing lift to windward to allow leeway coupling and develop lateral resistance for the boat particularly upwind.
In stronger conditions, when the main foil develops down force( upwind), the leeway components are greater than the vertical portion of the UptiP foil can effectively handle, there is a small extra component of lift to windward(due to downforce)-while the vertical portion of the ama foil is still working at 100%. The daggerboard is designed to be unloaded by the lee ama foil to reduce drag and facilitate leeway coupling.
However, it should be pointed out that the ama foil will still provide substantial vertical lift with little to no leeway coupling-like can occur off the wind. Lift substantially(and automatically) increases upwind because of leeway coupling.
----
Testing clearly shows the progression of the boat to full foiling from the problems encountered at the beginning-the last video is 100% proof that the foil system worked perfectly-regardless of any uninformed attempt to say otherwise. But testing is not done yet even though we reached a major milestone with the boat foiling in a 5 mph wind while using two different altitude control systems simultaneously. Hopefully, starting in June we'll get a lot more video and in stronger wind. But July 24th, 2014 was a major accomplishment for the boat after a great deal of development-and we will build on that this year.
Pictures "A" and "B" below clearly show the lee ama UptiP foil controlling altitude in two different speed and load cases- a clear demonstration of the value of an UptiP foil used in a trimaran configuration.
Attributes of the Fire Arrow foil configuration:
1) allows an oversquare trimaran to foil in very light air,
--
2) allows full foiling upwind and downwind completely automatically without any adjustments by the crew,
--
3) allows for retractable foils controlled from the cockpit,
--
4) allows the lee UptiP ama foil, with an AOI of +3 degrees, to unload the daggerboard(AOI zero degrees) for reduced drag and enhanced leeway coupling.
--
5) the foil system has considerably greater pitch authority than any conventional trimaran,
--
6) allows automatic control of the angle of heel of the whole boat,
--
7) allows automatic control of the ride angle of the lee ama UptiP foil.
--
8) allows mainfoil to automatically unload as the mainhull flies ,dramatically reducing drag.
--
9) allows automatic gust response with instantaneous increases in righting moment (automatically) as required.
--
10) allows a "Two Stage" ama that provides back up buoyancy if needed but allows the part of the ama that would normally make incidental contact with the water, to be as small as practical.(see pix below).
Final video(short version) of 2014 Testing showing full foiling. See full length version showing "glimpses" of the boat foiling upwind.

 

 

 

Doug - too long for my ADD.

 

Something new there or just recycled shit?

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I see the Great White Google Monster did it again.

 

Lake Pee politely explained to DumbLardass that Stereolithography does not build with metal at 4:06.

SL has always been plastic parts formed on a platform in a vat of light sensitive liquid polymer.

The process was invented, named, patented and a company formed, 3D Systems, in 1986.

 

Chris O followed up with additional details about the lack of experience, education and intelligence of The Doug Beast at 4:28.

 

Then DumbLoser made one of his infamous mad dash Google searches to "prove" his point.

AS USUAL, DirigibleLump found a website with matching search terms, his idea of "research", which he immediately posted a link to.

Had DistopianLouse actually read the result of his search, he would have found that the page was simply a listing of several machine shops and proto makers.

Had he actually looked at just one of the COMPANY website he would have seen that some of them do Stereolithogray AND several types of metalwork.

This groundbreaking revelation was posting at 4:45!!!!!!!!!

It took only 39 minutes for this scathing rebuttal to be posted.

Only 39 minutes to post a link to a website which proves that DL is the one who "don't know what (he is) talking about".

 

AS USUAL, the DL made a fool of himself by citing websites about things he has no education, experience, or knowledge of any kind.

 

ONLY 39 MINUTES TO MAKE A FOOL OF HIMSELF !!!!!!!!!!!!!!!!!!!

A NEW RECORD !!!!!!!!!!!!!!

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Stereolithography and Laser Sintering are two very different processes. One cannot produce metal parts with stereolithography. One cannot produce Titanium parts with stereolithography.

 

My apologies to Mr. Pee-it appears I misunderstood the comment made by another person regarding stereolithography and selective laser sintering.

This trumps everything I've found so far: http://markforged.com/ A printer that apparently prints with carbon fiber.

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Stereolithography and Laser Sintering are two very different processes. One cannot produce metal parts with stereolithography. One cannot produce Titanium parts with stereolithography.

 

My apologies to Mr. Pee-it appears I misunderstood the comment made by another person regarding stereolithography and selective laser sintering.

This trumps everything I've found so far: http://markforged.com/ A printer that apparently prints with carbon fiber.

 

Worth noting that it is not as strong as proper carbon. An interesting design, for sure, and a shitload more accurate than anything you will be doing by hand, provided you can create your desired shape in design software.

 

Have you ever worked out the approximate stress in you foils Doug? Do you have any idea if you are wasting time using carbon anyway?

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Here are some guys actually out getting some foiling done and look to be well on their way to making the crowdfunding work for their effort.

 

https://www.kickstarter.com/projects/647185563/rc-foiling-boat-for-international-competition

 

Doug, you could (make a donation) and put them over the top and then you will have actually contributed to foiling in a positive way! And look, they actually have a videographer too...

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Stereolithography and Laser Sintering are two very different processes. One cannot produce metal parts with stereolithography. One cannot produce Titanium parts with stereolithography.

 

My apologies to Mr. Pee-it appears I misunderstood the comment made by another person regarding stereolithography and selective laser sintering.

This trumps everything I've found so far: http://markforged.com/ A printer that apparently prints with carbon fiber.

 

Worth noting that it is not as strong as proper carbon. An interesting design, for sure, and a shitload more accurate than anything you will be doing by hand, provided you can create your desired shape in design software.

 

Have you ever worked out the approximate stress in you foils Doug? Do you have any idea if you are wasting time using carbon anyway?

 

 

The foils I build are tested to three times maximum load before they sail. They are relatively thin-9% T/C ratio. Definitely need carbon for stiffness.

As best I can tell, any 3D printer is too expensive for one off foils-(there are zero carbon printers large enough to print the foils I need in this area-from what I've been able to find;I expect that to change) -the hand built foils can be as accurate as the job requires and much less costly. Down the line it would be great to be able to print foils for someone to be able to supply proven foil sets for the AC 4.8 foiler class. Carbon/epoxy is great to work with especially when frequently modifying foils after testing.

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And if you cannot find a company with a big enough printer, you can print a kit of parts and assemble. With a bit of clever design, you will not lose strength. The great thing is the turn around time. You should be able to find somebody to print stuff that would mean you can have a new set of foils on the water in a week.

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I get my little printer in a couple months. We could run some RC foils in it to test it out. Use them as plugs

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Stereolithography and Laser Sintering are two very different processes. One cannot produce metal parts with stereolithography. One cannot produce Titanium parts with stereolithography.

 

My apologies to Mr. Pee-it appears I misunderstood the comment made by another person regarding stereolithography and selective laser sintering.

This trumps everything I've found so far: http://markforged.com/ A printer that apparently prints with carbon fiber.

 

Worth noting that it is not as strong as proper carbon. An interesting design, for sure, and a shitload more accurate than anything you will be doing by hand, provided you can create your desired shape in design software.

 

Have you ever worked out the approximate stress in you foils Doug? Do you have any idea if you are wasting time using carbon anyway?

 

 

The foils I build are tested to three times maximum load before they sail. They are relatively thin-9% T/C ratio. Definitely need carbon for stiffness.

As best I can tell, any 3D printer is too expensive for one off foils-(there are zero carbon printers large enough to print the foils I need in this area-from what I've been able to find;I expect that to change) -the hand built foils can be as accurate as the job requires and much less costly. Down the line it would be great to be able to print foils for someone to be able to supply proven foil sets for the AC 4.8 foiler class. Carbon/epoxy is great to work with especially when frequently modifying foils after testing.

 

Given the effect small changes to full scale foils makes, I suspect you are not as accurate as you think Think of the small changes made between iterations of moth foils, are you that accurate. How do you measure your foils, needle point micrometer? How much deflection do you get when you test to your 3x full load? How have you determined what the allowable deflection is? Getting 5 sets of foils to test a range of changes would be very simple with 3d printing, and you might even be able to determine if any of the features on your foils are having an effect.

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Guys... this is all really fantastically considerate, what with all the well grounded suggestions... but, Doug has zero CAD skills and that, ultimately, is the fly in the ointment as far as his possible foray into printed foils.

 

Until he makes the effort to be a decently modern practitioner of design systems, this is a dog that won't hunt.

 

.

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Guys... this is all really fantastically considerate, what with all the well grounded suggestions... but, Doug has zero CAD skills and that, ultimately, is the fly in the ointment as far as his possible foray into printed foils.

 

Until he makes the effort to be a decently modern practitioner of design systems, this is a dog that won't hunt.

 

.

Right, silly me, making the assumption that anyone attempting to design a complex 3 dimensional shape with multiple transitions in section and critical dimensions might be able to use some basic design tools. I can teach a student engineer to use Inventor or SolidWorks productively in 2 weeks, and they are lazy cunts. How many years have you been pissing around with this Doug? Autodesk products are probably the most cracked professional software around, excepting windows products, so getting a free version is a piece of piss

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The Doug-Bot has entered a new phase of frenzied logic responses.

 

The more dissent that is aimed at his ways and methods; the more he is reverting to publishing larger and more detailed irrelevant cut and pastes of other peoples work in some pathetic way to support his own venture.

 

I sense that the feverish spiralling is entering a new stage of heightened velocity (unlike his boats) that is going to end badly with shaky video footage of shoreline, trees, and some lurching hip hop, before he disappears up his own back side in cloud of putrid gas.

 

I feel a sense of deja vu. It was a year ago that he had proudly showed lots of static shots of the lawn ornament/toilet seat - but we had to endure some serious time delays before we ever saw 14 secs of "perfectly" controlled break dancing.

 

Anyone here local to Cocoa Beach who could verify how many unsuccessful voyages the Triangular Sandwich box has already had?

 

The need to hastily get some new foils (and a complete re-build) before we see "it foil perfectly on its first outing" or some other grandiose titled video, is highly likely.

 

The Doug-bot has already removed the previously stated wind limits, so what plague of pestilence or noxious weed will it be that stops are intrepid aviator?

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The cat seems to be heading the same way. After photos in the lawn, white stripes and all... nothing

come on doug, sail the models, they look great, you'll have fun sailing, modifying, repairing them, but if you dont sail they become static models

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Tremendous article by Dario Valenza on passive* Foils : http://carbonicboats.blogspot.com/

*wand controlled active foils work differently in two major categories: 1)wand controlled active foils that develop all the RM for the boat, 2) wand controlled active foils where the crew ,primarily, provides the righting moment.

 

Illustrations by Dario Valenza---Left-foil types related to RM. Right-foil types related to area:

post-30-0-85329200-1433371845_thumb.jpg

post-30-0-30048800-1433371861_thumb.jpg

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This is an experimental cat using 20 degree canted wand controlled T-foils. The cant helps to reduce the effect of high and low pressure on the same side of a conventional T-foil(see illustration in Post 1). Kevin Elway is part of the team and Alan Smith from Australia helped with development. Another very cool aspect of the Vampire foil system is that the windward wand controlled foil is retracted , like UptiP foils, making this configuration potentially very quick.

More info here: http://www.boatdesign.net/forums/multihulls/vampire-cat-canted-t-foils-51329.html

 

More on the Vampire here: http://www.catsailingnews.com/2015/06/m20-vampire-project-june-2015-update-q.html

 

picture from the link above by Tim Bees:

post-30-0-74939300-1434392013_thumb.jpg

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This is an experimental cat using 20 degree canted wand controlled T-foils. The cant helps to reduce the effect of high and low pressure on the same side of a conventional T-foil(see illustration in Post 1). Kevin Elway is part of the team and Alan Smith from Australia helped with development. Another very cool aspect of the Vampire foil system is that the windward wand controlled foil is retracted , like UptiP foils, making this configuration potentially very quick.

More info here: http://www.boatdesign.net/forums/multihulls/vampire-cat-canted-t-foils-51329.html

More on the Vampire here: http://www.catsailingnews.com/2015/06/m20-vampire-project-june-2015-update-q.html

 

picture from the link above by Tim Bees:

Looks stable.

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This is an experimental cat using 20 degree canted wand controlled T-foils. The cant helps to reduce the effect of high and low pressure on the same side of a conventional T-foil(see illustration in Post 1). Kevin Elway is part of the team and Alan Smith from Australia helped with development. Another very cool aspect of the Vampire foil system is that the windward wand controlled foil is retracted , like UptiP foils, making this configuration potentially very quick.

More info here: http://www.boatdesign.net/forums/multihulls/vampire-cat-canted-t-foils-51329.html

 

More on the Vampire here: http://www.catsailingnews.com/2015/06/m20-vampire-project-june-2015-update-q.html

 

picture from the link above by Tim Bees:

 

 

This looks as if it has the potential to be the fastest of all the current designs as there aren't any components of lift working against each other in different directions, and the foil tilts the right way for going upwind. I wonder though if canting the rudder to match would improve the handling and reduce drag - every time the wand makes the foil generate more lift it must push the middle of the boat to windward, but the rudder will lift straight up instead, requiring a steering correction. Also, has it sailed alongside a Moth, FP or F20 fcs yet to see where its performance is relatively better/worse? (I'm not concerned about how long it takes to tack or gybe at this point as there may be better ways of raising and lowering the foils.)

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Also, has it sailed alongside a Moth, FP or F20 fcs yet to see where its performance is relatively better/worse?

 

I don't know if it has sailed against Moths, but in the Round Texel it sailed against FP, F20fcs and other custom foilers. And while it is a chaotic race where you have to take comparisons with a degree of skepticism, this is their own report...

 

We were delighted with our performance during the first half of the Texel Race. We started cautiously, but quickly learnt to trust the wand in the large rolling waves. We led at the lighthouse feeling comfortably faster than the boats around. The leading boats arrived at the VC mark early, at least an hour before high water and we knew it would be shallow. So we stopped (still in the lead) to insert conventional straight daggerboards and to raise our rudders. Unfortunately one of the rudders slipped down and tore off when we grounded a few yards from the VC mark. Game over.

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If Kevin Ellway is involved it wil be well thought out. Some of the UK moth sailors have been doing some of the testing for the project. I believe there have been some scarey events, and this photo looks like one of them.

 

It has moth type wand control unlike almost all other cat foilers. ISAF have confirmed to the ACat Assoc that wand control does not comply with RRS 52 requiring all appendages to be manually controlled. The Moth Class changed this in its the class rules, no one else has, afik.

 

If the Vampire was alowed to enter the TEXEL, Rule 52 must have been discarded or ignored. If that is to be the case in other cat races and cat classes the foil design game will be thrown wide open again.

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One of the most exciting of the new wand based foilers is the Whisper 18. The modern pioneer of wand based systems for multihulls is Dr. Sam Bradfield who designed the Rave, SKAT(40') and Osprey foiling trimarans using his unique system. I had the great fortune to know Dr. Sam and to work with him one summer. We talked a lot about foiler design and it was his position that a Bradfield foiler had to have an oversquare platform to reduce the load on the foils in creating righting moment(RM). His foilers were equipped with dual independent wand systems, one for each main foil. Because they were independent, they reacted to the slightest heel of the boat increasing lift on the leeward foil and decreasing it on the windward foil. In fact, the RM generated by the widely spaced foils was so great that if the boat was sailed in too strong a wind it could break!

All this is what makes this foiler of particular interest to me because the Whisper uses dual independent wands on a narrow platform. That's the main obvious difference between it(and the fact that it is a catamaran) and Bradfield system with the other major difference being that the crew on the Whisper is used for active movable ballast. Now, Dr. Bradfields last boat, the 18' LOA by 22' wide Osprey also uses the crew for active movable ballast but the production Rave allowed the crew to sit in the center of the boat.
The last major designer to use a slight variation of the Bradfield system on a catamaran was Steve Killing on the C Class Rocker that turned out to be only about the same speed or slower than other C Cats. The Rocker used wands that were mounted forward on each hull(like a Moth) while the Whisper guys and Bradfield place the pivot of the wands near the center or aft of each main foil.
It appears that the Whisper is quite fast but the details of how they use the wand system will be interesting:

 

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If the Vampire was alowed to enter the TEXEL, Rule 52 must have been discarded or ignored. If that is to be the case in other cat races and cat classes the foil design game will be thrown wide open again.

 

I suspect if they had done well a protest would have resulted and the application of rule 52 would have really been tested.

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The lack of good information on performance may be a good sign then rather than a bad one. The way the foils are rotated up out of the way is horrific though - it's a long way to lift a lot of weight, it's causing them a problem with the width being measured with them both sticking out sideways, and it also means they can't partially raise a foil to use it below the windward hull to help prevent that hull touching down during lulls (positioned so that it is clear of the water most of the time).

 

Putting the foil to the outside of the hull rather than passing through it does look like the best place for it, but what you really want there is a canting case for the foil to pass through, mechanically linked to a canting rudder at the back. Ideally you would be able to remove the foil sideways from the case (or have a detachable case - either way though, you also want the foil to have a way of breaking free from the boat if it hits something hard so that an inexpensive component can take the hit instead of the foil or mast being written off) and then you would want to have an additional Tornado-style foil inside the hull for sailing in shallow water and for launching and landing.

 

What you would then have is a foiling system where the windward foil is raised less than with other designs (because it's horizontal and isn't going to dip in so often), there's less weight to raise (because there's less foil needed for flight if no part of it is working in a different direction to any other), it should provide better performance (again because it's generating all its lift in the same direction), and you can fit the foil after launch and remove it before landing. A problem remaining to be solved is how you link it to the wand - on the Vampire I'm guessing it's simple because the top is fixed in position and merely rotates, but that design limitation leads to a lot of work and substantial delays when gybing and tacking. On the Osprey the wand is attached to the top of the vertical foil and rises with it, but that means it isn't positioned ahead of the foil - maybe that doesn't matter greatly, so the solution may already exist.

 

[That may be close to the optimal solution, unless it turns out that it's better to use two smaller T-foils on each hull with one near the front and the other near or right at the back, one of them being steerable. I'm not convinced that balancing on one main foil in (or even behind) the middle is the best solution, though it may turn out (or already be known) that it is.]

 

There are objections to the idea of using wands, but if trying to avoid them leads to poor performance upwind due to uPtip foiLs sloping the wrong way, or greater drag downwind with oTher kiNds of foiL generating some unnecessary sideways component of lift, it's going to leave a lot of leading designs looking second rate. With a crew of two or more it might be possible for one person to steer the vertical component of the flight while the helmsman does the horizontal steering as normal (unless you're sailing at night), but I suspect the wand will eventually win out and the rules will change to allow it (and ultimately electronic systems), not least because there's a limit to how safe it is to have people locking themselves into flight-control tasks instead of being free to look around them at what's going on.

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What you would then have is a foiling system where the windward foil is raised less than with other designs (because it's horizontal and isn't going to dip in so often), there's less weight to raise (because there's less foil needed for flight if no part of it is working in a different direction to any other), it should provide better performance (again because it's generating all its lift in the same direction), and you can fit the foil after launch and remove it before landing. A problem remaining to be solved is how you link it to the wand - on the Vampire I'm guessing it's simple because the top is fixed in position and merely rotates, but that design limitation leads to a lot of work and substantial delays when gybing and tacking. On the Osprey the wand is attached to the top of the vertical foil and rises with it, but that means it isn't positioned ahead of the foil - maybe that doesn't matter greatly, so the solution may already exist.

 

[That may be close to the optimal solution, unless it turns out that it's better to use two smaller T-foils on each hull with one near the front and the other near or right at the back, one of them being steerable. I'm not convinced that balancing on one main foil in (or even behind) the middle is the best solution, though it may turn out (or already be known) that it is.]

 

There are objections to the idea of using wands, but if trying to avoid them leads to poor performance upwind due to uPtip foiLs sloping the wrong way, or greater drag downwind with oTher kiNds of foiL generating some unnecessary sideways component of lift, it's going to leave a lot of leading designs looking second rate. With a crew of two or more it might be possible for one person to steer the vertical component of the flight while the helmsman does the horizontal steering as normal (unless you're sailing at night), but I suspect the wand will eventually win out and the rules will change to allow it (and ultimately electronic systems), not least because there's a limit to how safe it is to have people locking themselves into flight-control tasks instead of being free to look around them at what's going on.

 

David the idea of the wand is to control the flight altitude of a foiler. When a wand is located as far forward as on the Vampire, the problem is that wave/wind induced pitching can cause the wand to change the lift on the foil-in other words, the response of the wand because coupled with the boats pitch.

And the idea that having the wand forward like that allows the wand to anticipate waves for the foil is just utter nonsense:

--at 5 knots the boat is moving 8.43' per second,

--at 8 knots the boat is moving 13.49' per second,

--at 10 knots the boat is moving 16.8' per second.

I estimate that the distance from the wand tip to the foil on the Vampire is around 8' so the wave that the wand reacted to will be long gone when the foil flap moves in response to it-especially above 5 knots of boat speed.

That and pitch coupling makes a forward wand a bad idea-especially on a cat, in my opinion.

picture from www.catsailingnews.com by Tim Bees:

post-30-0-68198400-1434587429_thumb.jpg

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I think you're right, Doug - the wand should probably be near the foil, so the Osprey solution could be the right way to go, just so long as it isn't too easy to stand on the wand and break it (the foil will be raised 2-3ft on the side you're on, so the wand's going to end up hanging around exactly where you least want it). I don't know how wands are normally connected up, so I don't know what the limitations are - can they be connected to the foil using a hydraulic cable? If so, perhaps putting the wand on the other side of the hull with it attached just ahead of the front beam might be a good place.

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There are multiple ways to connect a wand-in my opinion Bradfields is real good.I don't know the details of the Whisper but those wands appear to retract up thru the trunk. May be equally good.

post-30-0-50454800-1434660085_thumb.jpg

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Right, I didn't look carefully at the Whisper - it has the wands to the inside of the hull and further back than the foil, so that position has been tested and works fine, although a leeboard foil would be further away (sideways) and more so when canted, but any problem with it will be greatly smaller than the one of pitch with a wand way up at the front end.

 

[Edit: Just read your post again and rechecked the Whisper - the wands do appear to be directly in line with the foils, so they must fit in the case when the foil's raised.]

 

It looks from the Osprey photo as if adding a hydrolic cable should be all it takes to match the functionality while allowing the foil to be raised without the wand having to move with it, and hydrolic cables have been used successfully for recumbent cycle brakes with forces which are probably in a similar range. (Keeping the attached end of the wand at a fixed height matters if the raised windward foil is to be of any use in stopping the windward hull touching down - the foil needs to be angled to generate lift because otherwise all it'll do is add drag and make things worse.)

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So Doug, can you please explain why on Moths it has been found that the distance between wand an foil is important and that having the wand at or too near the foil leads to such poor foiling. There is a reason why a number of top boats are now placing the wand out ahead of the bow and I don't believe that your comment about waves has anything to do with it.

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The distance from wand tip to foil on the Moth is about half that on the Vampire as a percentage of the boats length, but nevertheless pitch coupling definitely occurs on the Moth-I've seen it happen. I'd imagine that the difficulty of rigging wands further aft is more trouble than it's worth, though I've seen a Moth with dual midship wands.

You can put a wand anyplace -even off the transom-and it will work but Bradfield and,apparently, the Whisper guys find the midship location best where there can be no pitch coupling. Pitch coupling won't affect anything in flat water(mostly) but may have a negative effect on boat handling in big waves.

From a previous post:

And the idea that having the wand forward like that allows the wand to anticipate waves for the foil is just utter nonsense:

--at 5 knots the boat is moving 8.43' per second,

--at 8 knots the boat is moving 13.49' per second,

--at 10 knots the boat is moving 16.8' per second.

 

illustration of pitch coupling / dual midship wand Moth:

post-30-0-36597000-1434674674_thumb.png

post-30-0-97210500-1434674901_thumb.jpg

post-30-0-76895900-1434676459_thumb.jpg

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