Extreme Dolfinism G2

[REVAN]

Here is video of my first real dynamic attempt since the Team World Championships in September 2012. I've basically done no apnea training since that competition. So, this swim felt pretty raw.



It was a 132m swim. I probably could have gone a little further, but stopped when I felt my fin break the surface. I figured it was a sign to come up, and I could tell that I wasn't in good enough shape to go for 150m without a good chance of having a bad day. The funny thing is, I got so excited about doing a dynamic again, I couldn't keep my heart from pounding. No matter how I tried to calm myself down, my heart simply remained too excited. I think my heart wants more dynamics...

 

[Philip Fennell]

One nice thing I should mention about this design, it does not require any modifications to the Pilot2 or drilling new holes in the frame to attach the floats. It is a true plug-and-play design.

Nice one @REVAN

 

[REVAN]

I was studying some dynamics from the California Cup competition I was at recently. I tend to do a lot of this type of analysis to help form a better picture of how things are working in the world of freediving equipment. I have notes stashed on a lot of different comparisons I've made over the years. I had written this one up in a way that could be fairly easily read and though I'd go ahead and share it here on the forum. This kind of thing is interesting to my inner nerd.

Here is a generic breakdown of the stats for my swim and a couple other divers using WaterWay Glide monofins. Ben is using a Glide with a fiberglass #2 fin blade. I'm not sure about Jenna's monofin, but I think it is probably a #2 also.

The following is an analysis of:

Jenna Mcgrawth's dynamic;


Ben Weiss's dynamic;


and Ron Smith's dynamic;


These swims were conducted at the "California Cup" pool freediving competition on August 16th, 2015. Metrics over the 50 meter pool were taken from the videos, and the number of fin strokes and the corresponding lap times are as follows:

Jenna with the WW Glide monofin (FG)
Lap 1: Strong push and 19 fin strokes with KKG technique in 39.7 seconds.
Lap2: Weak push and 24 fin strokes with KKG technique in 40.7 seconds.

Ben with WW Glide monofin (FG #2)
Lap 1: A push and 22 fin strokes with KKG technique in 39.5 seconds.
Lap 2: A push and 21 fin strokes with KKG technique in 37.0 seconds.

Ron with the DOL-Fin Orca Mk-2 monofin (Medium Tapered Blade)
Lap 1: Weak push (fin slipped) and 18 fin strokes with KKG technique in 36.8 seconds.
Lap 2: No push and 19 fin strokes with KKG technique in 37.0 seconds.

Comparing Jenna to Ron:
Approximate Stats for Lap1: Orca2 used 5% fewer strokes, and was 7% faster.
Approximate Stats for Lap2: Orca2 used 21% fewer strokes, and was 9% faster.

Comparing Ben to Ron:
Approximate Stats for Lap1: Orca2 used 18% fewer strokes, and was 7% faster.
Approximate Stats for Lap2: Orca2 used 10% fewer strokes, and was 0% faster.

Comments:

Jenna used a very strong initial push that accounted for several fin-strokes, but she also coasted that push out pretty far, which slowed her lap time. Even with the strong initial push, her first lap was only about 2% faster than her second lap with a weak push, even though she used about 21% fewer fin strokes on the first. Her second lap used a weak push that probably accounted for something equivalent to about 1 stroke and certainly not more than two.

My initial push was weak. I had not practiced in the pool to familiarize myself with the environment. When I pushed, the fin slipped on the wall tile and that took away some of the push that I was expecting. Despite the lost push velocity, I'm thinking it was probably still a little more effective of a push than Jenna's weak push she used on her second lap.

Based on the initial conditions, I think Jenna's and my second laps were more of a comparable set. It would appear that my initial push accounted for about one fin stroke; the time between my first and second laps were almost the same, but with 18 vs. 19 fin strokes. If Jenna's weak push accounted for one fin stroke also, we could compare my first lap to Jenna's second lap.

If we look at that comparison: The Orca2 used 25% fewer strokes, and was 10% faster. Nice easy to remember number! [ 25 & 10 ]

Ben had a good initial push and a good push on the turn. Our second laps were the same average speed, but Ben used a push at the wall and also used an extra KKG sequence to do it. On our first laps, we both started with a push, but the Orca2 used two fewer KKG sequences and was almost 3 seconds faster. It would appear that Ben's second lap went better than his first, like it took him a little time to find the right stroke rhythm.

Note - While it is interesting and useful to look at metrics like this, it is important to remember that these are stats for different swimmers, and technique can have a big impact on performance and metrics. None of us one was thinking about optimizing stroke counts in any of these swims. We were all just trying to go as far as we could, using whatever techniques worked the best for us.

I've competed with Jenna before. She is good. She was a national dynamic champion a few years back, but then again, so was I. However, she bested me in this competition!

Conclusion:

We should all make our own conclusion. For me, I still like swimming with my Orca2, and I think it performs up there with the best hyperfins available.

 

[Kars]

I would like to add the following - I assume knows this - :

- number of strokes, speed are not the only critical numbers to determine efficiency.
I could add effort level, level monofin technique, ease of use, swimmer's level of flexibility, buoyancy, and some minor influences I forgot.

To explain effort level, it's the amount of muscle and brainpower that is used to do the distance, how much O2 is actually used?


Test suggestion:

- if pool time and space permits; ask the monofin proficient athlete his and or her measurement and current fin setup, and have a foil ready to try after he/she did her dynamic.

Let her swim with the goal of efficiency, measured by the moment her first contraction starts; and have her surface upon that moment.
To amplify the difference, you can do small CO2 like schedule, like 3 dives, starting every 2'.

Cool to hear your inner nerd Ron!

 

[REVAN]

I would like to add the following - I assume knows this - :

- number of strokes, speed are not the only critical numbers to determine efficiency.
I could add effort level, level monofin technique, ease of use, swimmer's level of flexibility, buoyancy, and some minor influences I forgot.

To explain effort level, it's the amount of muscle and brainpower that is used to do the distance, how much O2 is actually used?


Test suggestion:

- if pool time and space permits; ask the monofin proficient athlete his and or her measurement and current fin setup, and have a foil ready to try after he/she did her dynamic.

Let her swim with the goal of efficiency, measured by the moment her first contraction starts; and have her surface upon that moment.
To amplify the difference, you can do small CO2 like schedule, like 3 dives, starting every 2'.

Cool to hear your inner nerd Ron!

Speed and strokes are the only things that are easily measured. The efficiency and O2 consumption are much harder to get, and easy for someone to fudge or make false statements to mislead. There's no way to verify the information without doing the tests yourself, so the information has to come from someone you trust, or it has no value. Though I wouldn't engage in lying about results on the basis of my ethics, as the designer of the monofin, I recognize that I have a vested stake in the product, and I don't expect people to trust my word on the issue. I try to only go into specifics on those things that are overtly observable (like stroke counts and speeds), and I avoid claiming specifics on the unobservable metrics like efficiency and O2 consumption and keep my comments to general impressions only...

...For me, I still like swimming with my Orca2, and I think it performs up there with the best hyperfins available.

Is it better or worse than other monofins? That probably depends on who is using it and how they are using it. I just know that I like it a lot, and the observable metrics look pretty good (including the national dynamic records claimed with Orca monofins).

For those other things, I had independent reviews done by freedivers who don't necessarily care if the products are successful or not.

https://www.deeperblue.com/dol-fin-lift-based-mono-fin-review-introduction/
https://www.deeperblue.com/dol-fin-monfins-review-part-2/
https://www.deeperblue.com/dol-fin-monofins-review-part-3-conclusions/

Like I said previously, "We should all make our own conclusion(s)".

 

[landshark sa]

Seeing as this is in a monfin area this question is more than a bit off topic...

But here goes anyway:
What's the possibility of doing bi-fins with foils?

 

[REVAN]

Seeing as this is in a monfin area this question is more than a bit off topic...

But here goes anyway:
What's the possibility of doing bi-fins with foils?

Bi-fins have constraint issues that are not very compatible with foils. The constraints force multiple foils laid out in a lattice arrangement that resembles traditional bi-fins. I was a consultant on the development of MaxAir scuba fins, which use many small foils.

http://www.tecreationdev.com/maxair.php

Before I got involved MaxAir fins looked like this:

I suggested modifying the shape of the foils and it resulted in a 20% improvement over the original design. Now they look like this:

The bottom line is that foils can be used in Bi-fin tech. It increases the number of parts that are involved by quite a bit, but it can have a limited hydrodynamic advantage, and can be worth the added expense in some cases (particularly in short scuba fin arrangements). The constraints and boundary conditions force the shape of the design in such a way that I don't think it can ever be better than a monofin for speed or efficiency.

So, learn to use a monofin and I think you will be a happier diver. The DOL-Fins are maneuverable enough that once you learn how to use it, you can do just about anything with them that you can do in bi-fins. It is hard to find representations of bi-fins in nature, and there are good reasons for that. Evolution has heavily favored the hydrodynamics of the monofin format because it almost always works better.

 

[landshark sa]

Thanks for the detailed response!

Although I know some of the guys use your fin for spearfishing and for sure a Pilot or X-20 is high on my list of diving tools I want to buy, for my application - 95% spearfishing and the way my crew and I dive, I think bi-fins are still the most practical.

On top of my wish list for bi-fins is to get the same performance out of a fin that’s much shorter than the long fins I normally use and I was hoping that a foil system could be the answer.

The reason for this is at 18ft my boat isn't very big and diving 3 or 4 up and moving from one fish shoal or pinnacle to another we usually end up with mess of fins getting in the way and crossing over each other. I know the easy answer is get a bigger boat, but from a practicality point of view 18 ft is really handy size, easy to tow and launch even in difficult situations.

Another application could be underwater hockey, where we sit with a comprise between straight line speed and manoeuvrability. It would be great if a foil system could provide the same speed as normal fin but in a much shorter and more manoeuvrable package.

 

[derelictp]

Hi,
Interesting analysis Ron.
I was developing monofins in 2003-2005 before the hyper-revolution if one can call it that and my fins back then was very similar like the Hypers but footpockets where lighter. I gave up because of the costs was getting too big for me.
I have been away from DB for some years and I really like following the Dol-fin development.

I have a question for you Ron;
-have you tried a Hyperfin that is tuned for you.
Why am I interested in that?
Because most people who make comparisons comes from a hyperfin background and it would be fair to hear the comparison from someone used more to the Dol-fin.

 

[Kars]

Hi Ron,

I've given the explanation here to help new people understand there is more to efficiency then number of strokes and lap times.
Surely you do right focussing on quantifiable and verifiable observations.

I posted the list/procedure in the hopes of someone taking up that challenge.

 

[REVAN]

Hi,
Interesting analysis Ron.
I was developing monofins in 2003-2005 before the hyper-revolution if one can call it that and my fins back then was very similar like the Hypers but footpockets where lighter. I gave up because of the costs was getting too big for me.
I have been away from DB for some years and I really like following the Dol-fin development.

I have a question for you Ron;
-have you tried a Hyperfin that is tuned for you.
Why am I interested in that?
Because most people who make comparisons comes from a hyperfin background and it would be fair to hear the comparison from someone used more to the Dol-fin.

I have tried a few different brands of hyperfins, but I don't have one myself. My main observations were that the fins I used felt squirrely and uncomfortable. Distance/efficiency seemed similar, but I didn't have an opportunity to use them enough to do a detailed analysis of their efficiency. The evidence from experienced hyperfin divers who have used the Orcas indicate that the Orcas and hyperfins are close to the point where it gets exceeding hard to measure a clear difference. If I were to do the tests, I figure I'd find the Orca2 to be better simply because my technique is optimized to make the most of the DOL-Fin tech. It wouldn't matter though, for the reasons stated previously. So, why bother? It would only create controversy with some people believing me and supporting my position and others calling B.S. and saying that I'm biased because I make the equipment. For now, I decided it is better to not tread in that territory.

I've often thought of buying a good hyperfin to do such a comparison, but haven't been motivated to spend the extra money to do that, especially since the results will be controversial regardless of the findings. It's just another expense that would ultimately need to be covered by DOL-Fin customers. My general feeling is that my big obstacle is keeping costs as low as possible, not in the fin's performance. So, it just hasn't seemed appropriate to direct money away from engineering & manufacturing improvements to backtrack on the hyperfin. With the latest generation of DOL-Fins, I have managed to get the prices down quite a bit from what they were a few years back. Unfortunately, most customers are overseas and the currency exchange rates have undone the savings for a lot of people.

 

[Kars]

I see your predicament Ron, it's a tough situation.
No one can argue with your NR Dynamic, maybe you can try for a CWT record? - Or sponsor the most promising CWT diver to improve the NR with your Orca2?

 

[REVAN]

I see your predicament Ron, it's a tough situation.
No one can argue with your NR Dynamic, maybe you can try for a CWT record? - Or sponsor the most promising CWT diver to improve the NR with your Orca2?

I seem to have issues with equalizing past about 60m. I've done up to 64 with the X-20 and feel I have a lot more swim left in me, but I don't think a CWT NR is in the cards for me. It is a bit of a predicament, so thanks for being understanding of the situation.

I was talking with Nick about having him try the Orca2 when it came out, but then he died before the product was ready. I was also recently considering contacting Natalia on the Orca2, but....

Truth is, it's been a rough couple of years, but I keep forging onward.

 

[derelictp]

I have tried a few different brands of hyperfins, but I don't have one myself. My main observations were that the fins I used felt squirrely and uncomfortable. Distance/efficiency seemed similar, but I didn't have an opportunity to use them enough to do a detailed analysis of their efficiency. The evidence from experienced hyperfin divers who have used the Orcas indicate that the Orcas and hyperfins are close to the point where it gets exceeding hard to measure a clear difference. If I were to do the tests, I figure I'd find the Orca2 to be better simply because my technique is optimized to make the most of the DOL-Fin tech. It wouldn't matter though, for the reasons stated previously. So, why bother? It would only create controversy with some people believing me and supporting my position and others calling B.S. and saying that I'm biased because I make the equipment. For now, I decided it is better to not tread in that territory.

I've often thought of buying a good hyperfin to do such a comparison, but haven't been motivated to spend the extra money to do that, especially since the results will be controversial regardless of the findings. It's just another expense that would ultimately need to be covered by DOL-Fin customers. My general feeling is that my big obstacle is keeping costs as low as possible, not in the fin's performance. So, it just hasn't seemed appropriate to direct money away from engineering & manufacturing improvements to backtrack on the hyperfin. With the latest generation of DOL-Fins, I have managed to get the prices down quite a bit from what they were a few years back. Unfortunately, most customers are overseas and the currency exchange rates have undone the savings for a lot of people.

That make sense. Keep up the good work.

 

[REVAN]

It's good to see other people's adventures with DOL-Fin monofins. These fins were specifically designed to blend the performance of a high performance monofin with the comfort, ruggedness and utility required of recreational diving equipment.

This looks like an epic wilderness adventure into the waters of British Columbia from Eric Fattah:



PS - if you didn't notice it, check out Eric's dive computer display, visible in some of the camera shots. Over 4 minutes showing on a dive to a wreck in 30m of water!

 

[MarcinB]

It even shows more than 5 minutes once

 

[Kars]

Looks like a great adventure!

I don't think those 4 and 5 minute dives where entirely done on 1 breath. My guess is that Eric may have taken 1 breath of his spare air bottle.

 

[REVAN]

...I don't think those 4 and 5 minute dives where entirely done on 1 breath. My guess is that Eric may have taken 1 breath of his spare air bottle.

You are probably right. For sure the 5 minute dive was with the pony bottle, as it was shown on the pre-dive setup. It may have been there and used on the first dive in the video as well. Just the same, wouldn't it be nice to have 5+ minute freedives, even if it is not per AIDA rules.

 

[Kars]

Eric is a pioneer, and I have nothing but great respect for him.
But at the same time I want to help people to stay grounded I don't mind the competition rules so much for recreational dives (although there are important safety considerations), It's just a heads up. Aside I don't think it's impossible as I've heard stories from a spear fisherman that included about 5 minute dives to 40-50m; though I think this is more of an exceptional individual.
One of mine personal dreams it to like a parabolic (flying like dive) to 30+ with a 4-5min dive time.

 

[Fondueset]

Eric is a pioneer, and I have nothing but great respect for him.
But at the same time I want to help people to stay grounded I don't mind the competition rules so much for recreational dives (although there are important safety considerations), It's just a heads up. Aside I don't think it's impossible as I've heard stories from a spear fisherman that included about 5 minute dives to 40-50m; though I think this is more of an exceptional individual.
One of mine personal dreams it to like a parabolic (flying like dive) to 30+ with a 4-5min dive time.

What Eric is doing requires discipline and actual MATH. It is a new discipline. NO_ONE should try it without a thorough knowledge scuba/mixed gas diving physiology. If you jump into it thinking you can simply grab a breath at 20m and stretch your dive you'd be better off jumping out of a jetliner when it flies over someplace you think looks cool.

I've been working with Ron's most accessible fin - The Pilot, lately. I'll be posting something about it as soon as I can.