Who dares to suggest a reason for this?

Yes, the V-bend Andy is referring to is definitely a bad thing. The question is what causes it. His theory is that it is caused by the shape of the blade - specifically, the cut-away 'shoulder' on the newer hyper style designs.

Mullins said:

Trux - the V-bend Andy is referring to is definitely a bad thing...

Click to expand...

Yes, I agree, that's exactly what I wrote. I hope it did not sound oppositely Is there any other thread about it, or do you both refer to the one I linked in my previous post?

I think it might be easier to run two stringers of uni-directional glass at about 20% each side of centre from the leading edge to 60-70% back. Fences on the wing tips (like C4 rails) work great on airplanes. No reason they wouldn't reduce drag on a fin, all else being equal. Wish I could get excited about building a mono Andy, but every time I kick one my TI hip says "don't ever do that again".

Two balls, two bone grafts, three new sockets and three operations (all on the same hip) plus four days in the hospital for a possible infection/rejection problem cost so much time and money that I think I'll hold-em. Besides I've become quite attatched to it.

Hi Guys,

I am the designer of the Lunocet. I have enjoyed reading this thread and thank you Trux for inviting me into it...

I really don't know where to begin, you guys are speaking my language and I have so much that I could comment on. I will try to be brief, however, as I'm not a fan of those who run off at the mouth.

The first thing I'd like to say to Harold is, "I believe you". That you are getting propulsion from a stiff, high aspect ratio mono with a some what proper foil shape, is probably very true... I will explain. The forces that a human can exert on the footpocket/plate area of a mono are quite extrordinarily high. I have broken many 7075 aluminum foot plates and am contstantly amazed that I did so. Therefore, I believe that Harold's mono is flexing every where it can. It is stretching the footpocket material, it is bending his foot... unless you really concentrate, the foot drops on the up stroke and you get angle there as well as a great many other places. However, for the most part, I would say you are slipping or stalling and it is very much drag based propulsion and very far from the elegant efficiency of nature's lunate tail swimmers.

To capture the power of the human legs and properly transmit it into a mono is a great feat alone... add to this the angle of attack issue and the fact that the proper angle of attack with respect to the resultant flow over the foil is not a fixed number but is dynamic and based on several ever changing variables, the robustness, streamlining, scaling, and comfort and you are talking about quite an engineering challenge. I am also the designer and producer of Zero Gravity road brakes for bicycles... so I am in the strength to weight game and play at the pro level. My brakes were named "the best brakes on the planet" by Bicycling Magazine. The reason I bring this up is because I want to illustrate how tough a nut the high performance mono challenge has been for me. You see I spent three months developing a world class braking system that knocked the likes of Shimano and Campagnolo on their butts in the arena of performance... but I have been in development of the Lunocet for seven years and I am just scratching the surface of what I believe is possible with a mono... It is my pursuit and belief that through perfection of technique, physical conditioning, and the proper refinement of the mechanics, materials, and geometry, I will breach a human completely out of the water on a Lunocet... I don't want to go into more detail at the moment. www.lunocet.com will launch around March 1 and there will be some rich info about the previous years prototypes, my discoveries, and my work with Dr. Frank Fish and our wonderful teacher, the dolphin. There will also be some reports coming to you from some very nice folks in this forum who have agreed to provide me with feedback on my first production run... '08 is going to be fun!

Thanks,

Ted Ciamillo

Hello Ted!

Thank you for your participating in this jolly freedivers forum And more thanks for taking up the challange to devellop a new model of monofin!
As Andy has illustrated, freedivers are pretty openminded and always keen on trying something new.

If you happen to have some spare hours, I would love to see a small video of you swimming a 50m apnea with your Lunacet fin. Offcause I would love to hear from a seasoned monofinner what he or she thinks.

Practiced monofinners make very much use of their flexeble back and muscles of them and belly, keeping their legs just pretty straid. I always enjoy watching monofinners with a fine whole body technique.

What is the weight of your current Lunocet?
Usually monofins are made for a particular cruising speed, what speed(s) is your designed for?

I quess you could spend hours reading and replying, so understandebly you can just pick and choose to your leisure

You got the DB communities attention, and maybe Dave want's to take your invention to new depths as your work does not appear to 'fold'

Love, Courage and Water!

Kars

This discussion just got a whole bunch more interesting. Very cool of you to drop by Ted.

If you don't mind, I'd like to ask does the Lunocet require a different technique than traditional monos?

Also, are you aware of the Life Amphibious project?

Looks like you and Alex might enjoy discussing together:
The Sub-Odyssey Project

Hi guys...

Thanks again Trux, Mullins, Ivo, Kars, and Jome.

I prepared this illustration for you today and I'd like to tell you a little about it.
First, to answer Jome's question about technique and also address what Kars said about the use of the back and abdominal muscles...

My goals for the lunocet include high performance in the areas of speed, agility, and efficiency. These requirements are pretty balanced in my book.
There are six speeds to this lunocet because there is a range of input on the part of the diver which, as Trux I think guessed, creates the proper amount of water pressure on the high pressure side of the foil to actuate the foil to the proper angle of attack... this is a critical and finely tuned parameter for operation and the different speeds (i.e. 1,2,3,4,5, or 6) will mean different things to different people because of differences in body strength, mass, length, flexibility, etc.
So, the swimming technique for the lunocet is very dependent on what you want to do and which speed you are in. For example, the straight leg, full body undulation would be used mostly in the lower speed settings (1 or 2) but as you move into the higher "gears" 3,4,5, and 6, more of the legs, and the power of the quadracepts as well as the power of the back and abs to achieve very high anaerobic bursts... the following illustration, I hope, explains further details...

for some reason the photo is not showing up... here is the link Lunocet

Wow, I see the design changed considerably!

I forgot to mention the reasons behind the change in design...

Although the proto-Lunocet you've seen in the video is a good design, there were some problems with it that this new design addresses. For one, the pitch axle has been moved forward. In the last design it was located near the toes and was also very forward on the foil itself - two problems here... the first, the axle being out at the toes and the foil even further back, there is a tremendous amount of strain on the ankles when one tries to engage one's full power into the mono... and after a few hours you find your ankles are extremely sore. The second problem, have the axle to far forward in the foil reduces the effective amplitude... you see there are dead spots as I'm sure you're aware, at the top and bottom of the stroke... what happens here is a reversal of pitch and direction but there can be a minimizing of loss or even a gain at this point if two things are done correctly. You see if the pitch axle is located just forward of the center of area of the foils, then you still have proper pressure actuation for angle of attack but the foil itself has to travel a much shorter distance in the amplitude to make the switch.

There is something else that can be done here... there is a rapid acceleration of the leading and trailing edges during this flip when the axle is closer to or even slightly aft of the foil shoulder and this rapid acceleration or "flick" at the ends of the stroke causes an interesting burst of thrust which I can only attribute to high lift when the vortices are shed in that fraction of a moment when all laminar flow breaks down before the switch. To sum it up... the pitch axle is in a more ankle friendly, and higher power transmission position and is more aft on the foil to facilitate the flick phenomenon and increased effective amplitude.

By the way, here are a few designs that we are planning to make available on the carbon... the "Deep Creature" (looks like a mermaid with white eyes) is art by Diane Ozmar, a very talented digital artist that I hope to get to work with us... Lunocet Designs


Thanks

Hi Ted,

Any ideas on pricing for these? Dealer arrangements?

PM me if these are not yet for public posting.

Cheers,

Peter

The new design looks cool, certainly a big change from the early prototype. Why are the footpockets canted outwards?

Adjustable tension would be fantastic. I imagine you might even be able to do this during a CW dive... What limits the pitch of the foils, is it just the rubber bungee or is there a solid stopper that prevents it going beyond a certain point? If so, can this also be adjusted? (just thinking about the possibility of overkicking on the tough stages of a CW dive if you have the tensioner set to 'soft')

Hi Mullins,

Sit down with your legs straight out and toes pointed and look at the angles of the top and bottom of your feet... do they look similar to the plates?

Pretty much dead flat across the bottom at the ball of the foot. Of course the tops of the feet are on an angle and there is a gap under the arch. I get the impression outward canted footplates would force the knees apart when the legs are bent?

Will have a good look at my mono(s) tonight and see how my feet sit in them

Ah, I see what you mean. Very nice.

I think you should hold a "breach the Lunocet" contest, Ted. I'll enter. I've been working on breaching with a regular monofin (old style) and have gotten out to my shins and then do the tail flip to make it look good. Or how about a Lunocet high jump competition on Youtube for your online promotions...

Pete