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MONOFIN HELLLLL!!!!! R.I.P Tritonfin
- Thread starterDivingDane
- Start date
Thread Status: Hello
, There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.
It can take a long time to get an up-to-date response or contact with relevant users.
Gotcha, that makes sense.
the performance figures you mention based on your program, what was the reasoning behind making this fin operate at these numbers?
is the fin designed for Freediving at a competitive level, Fin Swimming, or OCean touring? the reason i ask is that all 3 of these use fins with VERY different characteristics. and generally a fin that excels in one area does not to well in the other 2.
based on your 8 kicks to 25m and 15sec , then i figure the fin will fall into the Ocean touring style fin, as the speed isnt fast enough for fin swimming (not my specialty or anything i just know the record is somewhere down around 14-15 sec for 50m! and the number of kicks to the 25m doesnt seem to suiut competitive freediving.
sounds and looks like your fin is competing in the same market as the Lunocet?
DD
the performance figures you mention based on your program, what was the reasoning behind making this fin operate at these numbers?
is the fin designed for Freediving at a competitive level, Fin Swimming, or OCean touring? the reason i ask is that all 3 of these use fins with VERY different characteristics. and generally a fin that excels in one area does not to well in the other 2.
based on your 8 kicks to 25m and 15sec , then i figure the fin will fall into the Ocean touring style fin, as the speed isnt fast enough for fin swimming (not my specialty or anything i just know the record is somewhere down around 14-15 sec for 50m! and the number of kicks to the 25m doesnt seem to suiut competitive freediving.
sounds and looks like your fin is competing in the same market as the Lunocet?
DD
When I tried the Dol-fin the problems I had were a result of not having the foot attachments tight enough - but I did try it during our Lunocet trials and certainly, based on the lunocet we had at the time - the Dol-fin was superior.
The Dol-fin had no discernible drag - if the same holds true of the newer model than it is reasonable to suppose that it will glide quite well. My guess is that any 'x number of kicks for y distance' calculation is going to be based on a continuous kicking to achieve a certain distance/time - in other words it's not looking a glide - which is a big factor in dynamics.
The early model Dol-fin I tested felt like low-gear relative to my hyperfins or the lunocet. My guess would be it excels at cruise and glide - not so much acceleration - though it felt okay on the way up the line when I managed to get it straight on my feet.
The new one - if it has a good resting blade angle, may really excel in dynamics by virtue of good acceleration and low drag. A problem I could foresee for it as a touring fin is the risk of shearing force on the knees during any kind of twisting maneuver - a result of rigid foils.
Its interesting to see Seahiking or hydrotouring becoming a design criteria for monofins.
The Dol-fin had no discernible drag - if the same holds true of the newer model than it is reasonable to suppose that it will glide quite well. My guess is that any 'x number of kicks for y distance' calculation is going to be based on a continuous kicking to achieve a certain distance/time - in other words it's not looking a glide - which is a big factor in dynamics.
The early model Dol-fin I tested felt like low-gear relative to my hyperfins or the lunocet. My guess would be it excels at cruise and glide - not so much acceleration - though it felt okay on the way up the line when I managed to get it straight on my feet.
The new one - if it has a good resting blade angle, may really excel in dynamics by virtue of good acceleration and low drag. A problem I could foresee for it as a touring fin is the risk of shearing force on the knees during any kind of twisting maneuver - a result of rigid foils.
Its interesting to see Seahiking or hydrotouring becoming a design criteria for monofins.
The short answer is that I got that requirement from Peter. But, I did quite a bit of looking around to back that up as well. From a survey of videos I’ve been able to find on-line, 25 meters in 10 strokes and 17 to 21 seconds seemed to be typical of hyperfin performance. I did find one case where the diver did it in 20 seconds with only 6 strokes plus a partial. So, I felt that if I went with Peter’s recommendation, my fin would be in a good position to potentially eclipse the current state of the art.
I don’t want divers to have to sacrifice freediving performance, just to have something comfortable that they can use year round. My focus is to make monofins for sea-hiking. I believe that recreational freediving is the growth opportunity for freediving that will ultimately advance the popularity of the competitive side. So, these two aspects of the greater picture go hand-in-hand.
Fundamentally, sea-hiking and competitive freediving have the same requirement for efficient swimming, but sea-hiking imposes additional requirements for comfort and utility. It is actually a more difficult set of requirements to fulfill. Fin designers have been making compromises in performance to get acceptable levels of comfort in recreational monofins, an option that often ends up producing a product that really does not excel in any particular facet.
I am trying to change the paradigm by starting with an architecture that will inherently reduce the stresses and strains being applied to the diver’s feet and ankles giving it far superior comfort as compared to hyperfins. That way, I can optimize it for performance freediving and efficiency without having to make sacrifices to keep it comfortable for uses in sea-hiking. If it works, your sea-hiking fin may also be your competition freediving fin, which means you'll get more practice with it to better optimize your techniques.
Ron
Sounds good Ron! i hope it succeeds.
WOW, 17-21 seconds for a 25m Lap is pretty slow? the majority of divers i know, even in Bifins can failry comfortabley to 45sec to 50m just cruising, let alone actually trying a bit, i'm a pretty average monofinner if not below average and a 50m length i can comfortably do in 25sec or less, if i push really hard then around 21. bot saying the fin wont be good just not sure if your target performance numbers are going to represent what the average diver can do in a hyperfin (which is the target market)
really need to look at:
a) number of kicks to a length and work at reducing that as much as possible.
b) speed so how long to do say 25m or 50m.
these are 2 very different things because entirly different techniqgues are used for each.
in my view a) relates to energy efficiency, hydrodynamics and O2 conservation potential
B) relates to hydrodynamics and ppwer potential?
i dont believe that a bench makr of 10 kick and 20 sec to 25m is really demsonstrating what the fin can do.
i'll try a normal monofin during training tonight and try and get some figures for you over 25m for time and number of kciks as a combined figure.
i dont doubt the potential of your fin i just dont thing the measureable performances you are aiming for will suit competition Freedivers or Finswimmers (currently the biggest market for monofins), seehiking yes i think the fin will go well, again the on ly issue i would see with outn trying one is the width of the fin, not particularly compact for turning or looking around on a reef etc. just looking at the practicality of trying to manuever a 1m+ wide fin around a tree stump or through a cave in a reef?
DD
WOW, 17-21 seconds for a 25m Lap is pretty slow? the majority of divers i know, even in Bifins can failry comfortabley to 45sec to 50m just cruising, let alone actually trying a bit, i'm a pretty average monofinner if not below average and a 50m length i can comfortably do in 25sec or less, if i push really hard then around 21. bot saying the fin wont be good just not sure if your target performance numbers are going to represent what the average diver can do in a hyperfin (which is the target market)
really need to look at:
a) number of kicks to a length and work at reducing that as much as possible.
b) speed so how long to do say 25m or 50m.
these are 2 very different things because entirly different techniqgues are used for each.
in my view a) relates to energy efficiency, hydrodynamics and O2 conservation potential
B) relates to hydrodynamics and ppwer potential?
i dont believe that a bench makr of 10 kick and 20 sec to 25m is really demsonstrating what the fin can do.
i'll try a normal monofin during training tonight and try and get some figures for you over 25m for time and number of kciks as a combined figure.
i dont doubt the potential of your fin i just dont thing the measureable performances you are aiming for will suit competition Freedivers or Finswimmers (currently the biggest market for monofins), seehiking yes i think the fin will go well, again the on ly issue i would see with outn trying one is the width of the fin, not particularly compact for turning or looking around on a reef etc. just looking at the practicality of trying to manuever a 1m+ wide fin around a tree stump or through a cave in a reef?
DD
Keep in mind that the target of 25 meters in 15 seconds and 6 to 8 strokes is just one operating point in the design space. This is not the fastest it can go. The requirement did not come from speed capability. It came from what is a good power and stroke setting for dynamic with a hyperfin. So, it is more of a medium cruise setting. This requirement is probably not operating at the optimum dynamic efficiency for the Orca, but the goal here is to be able to demonstrate it can do this, even though it is a little like comparing apples and oranges.
I expect the load characteristics of this fin to be very different from a hyperfin which may skew the most efficient stroke cycle from where you are used to having it. When I get it in the water there will be a lot of testing to learn about its swimming characteristics and finding those optimum operating points. But, if we are going to get the most of its potential, we need to take care not to bring too many prejudices to the evaluation. This is not a hyperfin, so it will work differently and feel differently. That does not mean that its capabilities won’t be as good, or possibly better, if you are willing to adapt your technique to properly exploit the new equipment's potential.
Ron
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One tip Ron, have a decent mono finner demonstrate your work; it's not attractive when the diver displays a horrible technique, such as bending his knees excessively.
Maybe Martin Stepanek likes to help you out?
Succes Ron!
ps when I'm in tune with my 30 degree hyperfin I cruise for a max distance at 34-36 seconds a 50m, with about 16 continues strokes. When I do kick 'n glide, and I'm not good in that at all!*, I think I need about 12 strokes and 40 seconds for 50m.
I'm sorry to say but I'm not much of a potential buyer because of the price, even considering it's long term solid strength. I would like to try it though so I can share my opinion to others and discover for myself if I can adjust to and like the characteristics of this hydrofoil design.
*my friend needs about 31 seconds and 8 strokes a 50m lane, reaching 175m.
Maybe Martin Stepanek likes to help you out?
Succes Ron!
ps when I'm in tune with my 30 degree hyperfin I cruise for a max distance at 34-36 seconds a 50m, with about 16 continues strokes. When I do kick 'n glide, and I'm not good in that at all!*, I think I need about 12 strokes and 40 seconds for 50m.
I'm sorry to say but I'm not much of a potential buyer because of the price, even considering it's long term solid strength. I would like to try it though so I can share my opinion to others and discover for myself if I can adjust to and like the characteristics of this hydrofoil design.
*my friend needs about 31 seconds and 8 strokes a 50m lane, reaching 175m.