Extreme Dolfinism

[Fondueset]

Hey Kars, Just informational - but I have been playing with the Dol-fin for awhile - trying to get acclimated to where I feel I can fairly use it against my hyperfin. I think it takes a while to begin to appreciate it - like a hyperfin but without the pain . Eric Fattah has said he thinks it took him 1,000 dives with the Orca and I have benefitted from his experience. For myself, I feel pretty good with it now. I prefer the Orca foot design to cycling shoes at this point because it feels 'softer' - as you have mentioned. I think the flexible foot pocket of a hyperfin is replaced by ankle movement in the Orca. I have not found the learning curve difficult. Once the fin is on it is not so different than my hyperfin except - using the ankles more adds thrust - and the first kick does not feel very substantial. Once under way it provides good feedback. It finds it's efficiency with water moving over the foil. Experienced monofinners need a little time to get the best from the Orca - it is similar, but not exactly the same.In open water dives I have found it more maneuverable than a hyperfin. It has several additional advantages in open water - notably it is very good in cold water, less fatigue on the feet, less stirring of the bottom. Disadvantages are - it is wider than a hyperfin - and the strap system can be difficult (this is being addressed)I am at a point in my evaluation of the fin where it is very very close. I would not hesitate to use the Orca in a dynamic competition. Unfortunately PBs in my pool are probably not in the cards - though I was very lucky to be invited to use the whole pool before hours!With similar interval and distances it seems to me very close with my Starfins.

 

[Kars]

The problem with Hyperfin pockets is that they are not fitting the foot closely without stretching the rubber.
The foot stretches the rubber footpocket at places, but that tension, squeeze, is tiring the foot muscles over time.
Nylon cycle shoes do not stretch as much, therefore do not tire the feet with squeezing pressure.
However I've found that arching my feet down (toes arching down too), helps with streamlining and orientating the fin in line with the legs and body. I short hyperfin pockets do have their weaknesses, but also have their strengths.

An ideal footpocket for me, would have pointed down toes, be near rigid , evenly distributed light foot squeeze and a moulded fit.

---
"Softer feel", I think I should clarify this more.

I do NOT mean the squeeze of the footpocket on the foot.
I mean the initial stiffness of the suspension. The moment one starts applying down force, the initial energy is stored, and partially returned later in the down stroke. If you have a stiff rubber hyperfins footpocket the initial stiffness is high and sudden, it feels like you're pushing down a plank.
I suspect that the Lunocet design does have a suspended take up trajectory.
This exploration of the subject demonstrates to me that making a good comprehensive review of monofins rather difficult, since all these aspects are so subtle and difficult to relate to an audience not used to terms describing parts of monofin hydrofoil actions.

 

[Fondueset]

The problem with Hyperfin pockets is that they are not fitting the foot closely without stretching the rubber.
The foot stretches the rubber footpocket at places, but that tension, squeeze, is tiring the foot muscles over time.
Nylon cycle shoes do not stretch as much, therefore do not tire the feet with squeezing pressure.
However I've found that arching my feet down (toes arching down too), helps with streamlining and orientating the fin in line with the legs and body. I short hyperfin pockets do have their weaknesses, but also have their strengths.

An ideal footpocket for me, would have pointed down toes, be near rigid , evenly distributed light foot squeeze and a moulded fit.

---
"Softer feel", I think I should clarify this more.

I do NOT mean the squeeze of the footpocket on the foot.
I mean the initial stiffness of the suspension. The moment one starts applying down force, the initial energy is stored, and partially returned later in the down stroke. If you have a stiff rubber hyperfins footpocket the initial stiffness is high and sudden, it feels like you're pushing down a plank.
I suspect that the Lunocet design does have a suspended take up trajectory.
This exploration of the subject demonstrates to me that making a good comprehensive review of monofins rather difficult, since all these aspects are so subtle and difficult to relate to and audience to used to terms describing parts of monofin hydrofoil actions.

 

[cdavis]

Lawn poem is a hoot!

 

[Fondueset]

Hi Kars,

Good subject! For my part - the foot pockets on my star fin are snug but soft. I can wear it for hours and hours with almost no discomfort. (I think my record is 4 hours). ( Really this is the first hyperfin I have found that is so comfortable and yet swims very well - not to rant, but the fin is almost unbelievably well balanced). I think most people would consider the pockets loose - because my foot moves slightly inside them while swimming - but I have observed that this too stores energy. I might want a tighter fit for depth or sprinting, but for dynamic this one is wonderful. Obviously I can make it tighter with socks. When swimming I try to let my toes be passive - I find no advantage in making them tense as the leverage for operating the fin really comes from the larger structures of the foot.

I believe your finding about toe pointing has to do with blade angle. Three ways to level the blade are to raise the legs or bend the knees or point the toes as you say - this last stretches the top of the foot and contracts the arch - pointing the Hyperfin blade more upward relative to the body. The 28 degree angle on my Starfin does not require much to keep it level. Alex Lichenko has told me that he will add slightly more angle to my next fin -( which I am quite excited about!)

This also brings an interesting point about hyperfin design. The heel is left uncovered. It is part of the leverage on the downstroke because of the rigid structure inside the bottom of the foot pocket pushing into the front of the heel. But also allows freedom of movement for the parts of the foot forward of the ankle/heel. This makes it possible for the flexibility of the foot itself to contribute - both passively and actively.

A difference with the mechanical fins (Dol-fin and Lunocet) is, as you point on, in the energy storage. There is a slight buffer in the mechanism that the blade attaches with - but essentially the Orca does not really store much energy (at the same time - it does not take much energy to generate forward motion.) Instead it works like an airfoil flying through the water - and becomes more efficient when water is moving over it.
This is where I think the potential for advantage is with these fins - their efficiency in this regime and their very low drag. They feel different than hyperfins - and this can be disorienting in the beginning. It has been my feeling that the first kick is not very satisfying - however - the second kick - with good streamline - is very good, as are all of them after that. You can feel the foil really likes water moving over it and the faster you go the more you get with less movement. I think there is an energy/time equation for these fins that I've yet to zero in on.

I am not fond of cycling shoes because they are very stiff. (I'd rather have something like cross country ski shoes - with flexibility built into the sole - which would then become energy storage. ) The feet are essentially locked into a rigid structure that does not feel organic to me. (I need to spend more time with them for sure - opinion subject to revision). The Orca has an arrangement that will let you wear any sort of socks up to probably 6 or 7 mm without a problem - in fact such socks make the fin feel more natural.

- Thanks Connor. I have to suppress my thoughts while mowing - lest I produce a tedious novel.

 

[REVAN]

Hi Ron,

I'm very pleased to see some useful in pool comparisons, and I hope for more, preferable in a flat 50m pool for more consistency.
Though it's always fun to use the times and number of strokes in hypothetical calculations, I think a true confirmation would be a bunch of good monofinners doing pb's with only a short adaptation time....
You see, and I assume you know, there are many more factors involved in an efficient design....

There are many, many factors and it is very difficult to get a good read of a fin's performance, especially when the two fins being compared function so differently. All this has been explored in depth earlier in this thread. I was trying to get a more indepth discussion of this comparison, specifically comparing videos #1 and #3.

Fondueset said, "Easily equivalent - no question".

That statement leaves open the possibility of it being a little better, so I thought I would explore that 'possibility'. Had this been a video of me doing the comparison, I could speak in more detail about the feel of the experience and provide my personal impressions (but everyone would assume I am bias and be skeptical of my comments). As this was someone else's swimming experience, I can only comment on the content observable in the videos, so that is what I did. I looked at the times and the stroke counts and made comments on that to spur further discussion. I'm sure that the truth is a mixture of better and worse depending on a number of factors, with the Orca prevailing some of the time and the hyper prevailing some of the time, but always close in performance.

As for the PBs and comparisons, this is difficult to arrange. One reason for the Orca redesign is simply to make them more available and increase their prevalence among freedivers. The current design is so difficult for me to make that I have had to turn customers away because I didn't have the time to make it for them. With such a small fraction of divers using Orcas, getting meaningful PB comparisons is not really possible. However, a different statistic that may be interesting is that there are only 4 people I know of that compete with Orca monofins, and half of them have set Dynamic records with them. At 50%, it is hard to imagine the Orca could possibly be a handicap. It is easier to imagine that it could be an advantage.

On your new design, maybe you can think of something that prevents or reminds the swimmer to keep the toes strait....

...An ideal footpocket for me, would have pointed down toes, be near rigid , evenly distributed light foot squeeze and a moulded fit....

Already on it, Kars; well, except for the part about being moulded. But, this is something I wanted to explore. As I have not tested it yet (prototype still in construction), I don't know if it will be in the final design, but I will be evaluating it.

 

[Fondueset]

There are many, many factors and it is very difficult to get a good read of a fin's performance, especially when the two fins being compared function so differently. All this has been explored in depth earlier in this thread. I was trying to get a more indepth discussion of the comparison.

Fondueset said, "Easily equivalent - no question".

That statement leaves open the possibility of it being a little better, so I thought I would explore that 'possibility'. Had this been a video of me doing the comparison, I could speak in more detail about the feel if the experience and provide my personal impressions (but everyone would assume I am bias and be skeptical of my comments). As this was someone else's swimming experience, I can only comment on the content observable in the videos, so that is what I did. I looked at the times and the stroke counts and made comments on that to spur further discussion. I'm sure that the truth is a mixture of better and worse depending on a number of factors, with the Orca prevailing some of the time and the hyper prevailing some of the time, but always close in performance.

As for the PBs and comparisons, this is difficult to arrange. One reason for the Orca redesign is simply to make them more available and increase their prevalence among freedivers. The current design is so difficult for me to make that I have had to turn customers away because I didn't have the time to make it for them. With such a small fraction of divers using Orcas, getting a meaningful PB comparisons is not really possible. However, a different statistic that may be interesting is that there are only 4 people I know of that compete with Orca monofins, and half of them have set Dynamic records with them. At 50%, it is hard to imagine the Orca could possibly be a handicap. It is easier to imagine that it could be an advantage.




Already on it, Kars; well, except for the part about being moulded. But, this is something I wanted to explore. As I have not tested it yet (prototype still in construction), I don't know if it will be in the final design, but I will be evaluating it.

Hey Ron,
Yes, I think there is definitely the potential for it being better. My phrasing was intentional I wanted to approach this by getting the Videos up and letting those be the conversation starters - rather than immediately fill it up with my impressions. Also - as I've mentioned, the Videos themselves are a bit of a revelation to me.I think your remarks and observations are very apt and useful to everyone.
I will add here that, now that I've gotten used to the shallow water starts with the Orca - which at first were awkward and energy consuming to me - the energy expenditure for the two fins seems very close. As mentioned - I'm looking forward to shooting longer swims without the toe handicap.
With the smaller blade the Orca was definitely not as close with my Starfin, I could very definitely see the difference - now there is really very little light between them. But I want to reiterate that the primary thing I am focused on while swimming - in addition to exploring and refining all aspects of technique to optimize performance - is energy expenditure. And again, in this regard it's incredibly close.

To test this I play with the intervals between laps - rather than going for distance or time PBs.

 

[Kars]

No worries Ron, I understand and appreciate you value integrity. I only wanted to point out to the uninitiated that doing a simple number and time calculation does not say much about efficiency in freediving. The same goes for DNF.

On Orca2 development.
About design gripes I have with current design, is the strait, thin, wide blade.
Have you experimented with a narrow, arrow or bow shape broader sized foil? (more like airliner wing shaped instead of glide plane wing)

Good to hear you're working on improving the design for ease of manufacturing.

I think instruction of this sophisticated tool is important. As a swimteacher I see many children using a lot of force and not getting speed. They think: more power=more speed. This is partially true, much less so when there is bad technique and no thrust. I think this applies especially to the hydrofoil design.

---

Fondue, I like your Lawn Poem! - Awaiting your Orca Poem

Thanks for the more detailed reply, good to hear you hyperfin fits you well.
From the video's, and I know you changed your technique because of your toe injury, I see how this increased your body amplitude and reduced your blade amplitude. I hope your toe gets better soon. I suggest for the next video starting from the shallow side, this way it's easier to get at the proper depth and rhythm.

 

[Fondueset]

No worries Ron, I understand and appreciate you value integrity. I only wanted to point out to the uninitiated that doing a simple number and time calculation does not say much about efficiency in freediving. The same goes for DNF.

On Orca2 development.
About design gripes I have with current design, is the strait, thin, wide blade.
Have you experimented with a narrow, arrow or bow shape broader sized foil? (more like airliner wing shaped instead of glide plane wing)

Good to hear you're working on improving the design for ease of manufacturing.

I think instruction of this sophisticated tool is important. As a swimteacher I see many children using a lot of force and not getting speed. They think: more power=more speed. This is partially true, much less so when there is bad technique and no thrust. I think this applies especially to the hydrofoil design.

---

Fondue, I like your Lawn Poem! - Awaiting your Orca Poem

Thanks for the more detailed reply, good to hear you hyperfin fits you well.
From the video's, and I know you changed your technique because of your toe injury, I see how this increased your body amplitude and reduced your blade amplitude. I hope your toe gets better soon. I suggest for the next video starting from the shallow side, this way it's easier to get at the proper depth and rhythm.

 

[Fondueset]

In response to Ron's (implicit )suggestion to mention more about the feel of the Orca, and having taken some time to digest the videos and think about my open water dives as well as the various pool sessions - here is a touchy-feely opinion piece:

The first time I took it out in open water I was delighted.
I thought it would feel much more mechanical and I was worried about having to alter the lovely feeling of whole body undulation. It was a pleasant surprise across the board.

I was unimpressed with it's surface performance, but it felt great cruising at depth and gliding. When I took it out again, after the water began to cool and in my 5 mil suit - I'd modified my surface technique a little and it felt better in that regime. It still felt good cruising but was markedly inferior to my hyperfin in the vertical. It was a struggle to power through the buoyancy of my 5 mil suit on the way down.Ease of maneuver at depth during photo sessions was less awkward than the hyperfin - with less of a problem with stirring up sediment.

Ron then sent me the shoe model with a wider blade, which I promptly moved to the Orca. This immediately felt like a winning combination. Surface swims were better, vertical dives seemed to be at parity with the hyperfin and Horizontal swims, and glides, were even better than they had been. The extra couple of inches had no noticeable impact on maneuver.
Now - as to how it felt during the Video shoot: Everything felt like crap. My toe was crushed into the hyperfin and the pain was only barely tolerable while I was swimming - when the fin pulls a little away from my foot. Standing still was almost unbearable and gliding wasn't much better. The downstroke and turns were not pleasant.

In the Orca I felt like I wasn't getting anywhere, that I was swimming sideways and that my technique completely sucked. I wasn't looking at my times or doing stroke counts - just trying to do as many laps as I could during the time we had the pool to ourselves and do a halfway decent job despite the pain. The only objective observation I made WHILE I was swimming was that the Orca hurt less and did not require any more energy than the hyperfin. It FELT slower just like it FELT Like I was swimming sideways. The videos pretty much blow all that negativity out of the water - no pun intended.So - here are a few definite things I have to say.

The Orca is very comfortable and will probably never break.
Once under way - which just takes one full kick - it is very efficient and does not require much to keep going.
Feedback is different than with a mono fin - it does more than it feels like it is doing.
It does NOT require a radically different technique.
It DOES respond very well to a good whole-body undulation.
Having used a Hyperfin before the Orca is an advantage - just remember the feedback difference.

Things I'd change -

The Straps - they need to be easier to use and to lock down in a more positive way.(in progress)
The metal footplates - they are okay with a thick sock - but I'd like to see something more contoured (and less cold!).
An option might be to just wear something with a sole in it.
(I too wouldn't mind seeing a shallow 'v' or curved foil - particularly for recreational models.)
What I think - I think the Orca with about a 30" (without tips) blade is at parity with my #3 Starfins Hyperfin. I would not hesitate to enter a dynamic competition with it.*
(I've not yet come up from enough deep dives with it to say one way or another about depth)

*I am by no means done getting the most out of the Orca - my opinion could change - but probably only for the better.

Given the very low drag of the Dol-fin foil - and the difference a couple of inches made in my impression of the Orca's performance, I think it is reasonable to think that another inch or two will improve it even more.The Orca is Ron's flag-ship design. It is the one to evaluate with an eye to competitive diving. I'll be evaluating his recreational fin design - which is extremely cool, btw - with more of an eye toward fins like the Waterway Nemo.

I think it's time to take the Orca off probation. Ron has done some fine competitive work with it, Eric Fattah has practically put his Chen Bin in retirement and I think it at least matches one of the finest mono fins available.

 

[REVAN]

So, I'm working on improving the surface swimming qualities for the Orca Mk-2. I am also looking at changes to the strap system to make it work better for others. I like the existing strap system a lot, but several other people have had less positive impressions. It works, but it could probably be improved also, so I'm working on that.

I am also attempting to get an additional degree of streamlining through some subtle changes to the shape of the foot support and fairing. Streamlining is always a tricky thing, so we'll have to wait to see if the effort is going to be successful.

 

[REVAN]

And, yes... Eric Fattah has retired his Chen Bin. He does not compete anymore but he dives beyond 200ft (61m) recreationally in a 7mm wetsuit while using his Orca.

 

[Fondueset]

And, yes... Eric Fattah has retired his Chen Bin. He does not compete anymore but he dives beyond 200ft (61m) recreationally in a 7mm wetsuit while using his Orca.

View attachment 37463

Among the peoples of Earth, Eric is at the very top of the list of those whom I trust to accurately evaluate Freediving equipment. Here is his review - (fyi - his Orca has an even wider blade than the one I am using). Frankly I can only assume the reason everyone didn't run out and buy one immediately after reading this is that they don't know Eric.

http://www.deeperblue.com/gear-review-the-dol-fin-orca/

 

[REVAN]

To close out the 2013 year, I'll share a new video with my Deeper Blue friends. This video was shot in West Palm Beach, Florida. The reefs and sponges there right off the coast of Florida are surprisingly beautiful. They have some nice ship / artificial-reefs placed in the area as well for "clean" wreck-diving. If you are in the area, I highly recommend you check it out. I am doing a scuba demo with the DOL-Fin X-15, and Ryan Myers (a local spearo) swapped out his bi-fins for a new exo-skeletal frame DOL-Fin with cleaner looking lines than the X-20.

I have not officially named the new design yet, but have been calling it the X-22 during development. It is likely to go into production in the spring of 2014. It is about two pounds more heavy than the X-20 making it slightly more burdensome to travel with, but it floats which is good for free-fall stability and breathing-up on the surface. It also looks pretty nice. I have not decided if it will replace the X-20 or be a parallel product. Please let me know what you think of the new design and if you like the name X-22 or if you have another good idea for a name you want to suggest.

Video posted here: http://content.jwplatform.com/previews/Snp3jfQ3-C3PNGnB0

- Special thanks to Dan Volker, dive tourism director of W. Palm Beach for creating this video.

 

[noa]

Very nice looking new fin. The new skeleton looks like quite a hydrodynamic improvement over the X 20.
I would love to see the shoes positioned a little lower and "out of the way" of the frame as they protrude a little as they are now.
Another wish I would have is a sliding footplate system, so one can select their shoe-frame angle depending on swimming style and ankle flexibility.
Look forward to seeing more pictures of this as it appears to be very promising indeed. Congratulations.

 

[REVAN]

Very nice looking new fin. The new skeleton looks like quite a hydrodynamic improvement over the X 20.
I would love to see the shoes positioned a little lower and "out of the way" of the frame as they protrude a little as they are now....

I'm not quite sure what you mean by "shoes positioned a little lower and "out of the way" of the frame". Please elaborate.

Also, this is not a streamlined design like the Orca. It uses shoes like the X-20 and has similar drag and performance characteristics. I had previously experimented with streamlining for the shoes, but in the end it just was not worth it. It would have ended up costing as much as an Orca, but it would not work as well as an Orca.

Therefore, the shape of the float system on this fin is primarily aesthetic. If you want a monofin that is actually streamlined and has the performance advantages of streamlining, you will want an Orca. Streamlining is tricky and the shoes interfere with it to the point were it is best to start with something dedicated to the task. That's why I'm working on the Orca Mk-2.

...Another wish I would have is a sliding footplate system, so one can select their shoe-frame angle depending on swimming style and ankle flexibility....

This feature you describe is primarily handled with the trim plate selection. The shoes move as well and can be adjusted to change the lever-arm to the fin, or to adjust one shoe relative to the other for people who have asymmetrical leg lengths.

 

[wjohnson100]

Hi all. As background, I am a DOL-Fin man. I have used Ron's fins for several years, and love them. I had never done any swimming with a normal monofin until recently, so I had no basis for comparison. The only thing I will say about my swimming with the normal monofin is that it felt totally foreign to the feel of the DOL-Fin.

For me, the ORCA rules the DOL-Fin kingdom. I am currently using the 32 inch blade (sans extensions). I have an X-20 as well, and love it too, but for pure raw power and efficiency, the ORCA rules. I did make one major modification in the straps as you can see here.

The heel straps are independent of the main straps, so the main straps are set and then never adjusted again unless you want to. On the main strap, the clips to the outside are regular tension locks and provide the adjustment. As kind of a temporary measure I also used tension locks in the four middle clips. Their function is to lock the strap in place. It is not clear here, but my main straps are now sewn in place to lock them, so the middle four tension locks are no longer necessary. The tension locks on the heel straps work alone and the excess strap you get when done is tucked nicely into the fin. One weakness here is that when I was making these, I could only get nylon straps, so eventually I will get proper polyester and make new. High strength tension locks are easy to get, so that is no issue at all. When I started modifying the straps, I used side release buckles for the heels, but I found them to be unnecessary.

As an added benefit, the heel straps now make good handles. In fact, if you are as clumsy as I am but still want to put the fin on in the water, you can attach a lanyard to one of the heel straps to secure it until your foot is securely in the other side.

The whole reason I did all of this was to allow independent adjustment of the heel and main straps, and to improve comfort by ditching the metal. I still wear a neoprene sock to keep my bare feet off the metal. I have worn this strap configuration for many hours at a stretch with no discomfort.

I suspect Ron will address the strap issue with the MK II. I am sure that however he fixes it, his solution will be a bit more elegant than mine.

Can't wait to see what else is in store for us.

 

[Fondueset]

Hi all. As background, I am a DOL-Fin man. I have used Ron's fins for several years, and love them. I had never done any swimming with a normal monofin until recently, so I had no basis for comparison. The only thing I will say about my swimming with the normal monofin is that it felt totally foreign to the feel of the DOL-Fin.

For me, the ORCA rules the DOL-Fin kingdom. I am currently using the 32 inch blade (sans extensions). I have an X-20 as well, and love it too, but for pure raw power and efficiency, the ORCA rules. I did make one major modification in the straps as you can see here.

View attachment 37500

The heel straps are independent of the main straps, so the main straps are set and then never adjusted again unless you want to. On the main strap, the clips to the outside are regular tension locks and provide the adjustment. As kind of a temporary measure I also used tension locks in the four middle clips. Their function is to lock the strap in place. It is not clear here, but my main straps are now sewn in place to lock them, so the middle four tension locks are no longer necessary. The tension locks on the heel straps work alone and the excess strap you get when done is tucked nicely into the fin. One weakness here is that when I was making these, I could only get nylon straps, so eventually I will get proper polyester and make new. High strength tension locks are easy to get, so that is no issue at all. When I started modifying the straps, I used side release buckles for the heels, but I found them to be unnecessary.

As an added benefit, the heel straps now make good handles. In fact, if you are as clumsy as I am but still want to put the fin on in the water, you can attach a lanyard to one of the heel straps to secure it until your foot is securely in the other side.

The whole reason I did all of this was to allow independent adjustment of the heel and main straps, and to improve comfort by ditching the metal. I still wear a neoprene sock to keep my bare feet off the metal. I have worn this strap configuration for many hours at a stretch with no discomfort.

I suspect Ron will address the strap issue with the MK II. I am sure that however he fixes it, his solution will be a bit more elegant than mine.

Can't wait to see what else is in store for us.

Nice!
I'd love to try the Orca with a 32 inch foil. I don't know what the point of diminishing returns would be - but in terms of the effort - return equation - the model I'm using has only gotten better with the wider foil.

 

[wjohnson100]

Yea, I like the ORCA foil. I wonder how a 32 inch foil would work on the X-20. At some point though, it would get so wide it would start to interfere with turns. I can tell the difference in DYN turns with the ORCA as opposed to the X-20. Still is not too hard and I can do several different turn types with both fins. The video below demonstrates three monofin turn types in both the right hand and left hand directions. Ron's normal turns with the ORCA are single axis turns (I call them flat-spin turns) and are not demonstrated here.

 

[REVAN]

DOL-Fin X-20s at Nemo 33:

http://www.universal-freedivers.be/article-belle-affluence-d-apneistes-hier-a-nemo33-122041051.html