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Longer Monofin any good ?

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.


Oz freediver
Oct 3, 2001
Hi All,

I talked to a guy in NewZealand who makes his own fins, and he was keen to make me a custom one. I told him I wanted it for freediving and he had an idea to make a longer then normal fin. He thinks with a longer fin & a larger amplitude undulation may help efficiency.

Can anyone see the advantages or disadvantages of such a fin ?

Looking at it from a finswimming point of view, a larger fin would make turns more difficult. Perhaps the reason why fins are the shape and size they are from a number of factors including
- being able to turn
- diving off the blocks
- rotating & general motion coming out of a turn

So speed & efficiency may not have been the only factors that have determined the monofin design over the years ?

If somehow a standard fin shape&size is the optimum for speed&efficiency, then how would this work for both small & large divers ?

ie for the same motion relative to size, a taller diver should have larger or longer fins, make sense ?

I have used a Waterway LD1 fin and found this good for freediving although maybe a bit on the soft side. So I have asked for a fin in between "soft" & "medium". (I normally use very stiff bi-fins)

Model2 Medium distance

I really don't know about the length of the monofin. i can understand that it should suit a slower stroke (larger amplitude). But what is the optimum length?- i have no idea. That has to be down to trial and error? :confused:

I also currently use a Model1 LD, but have recently bought a Model2 LD, which probably suits me better as I only weigh 70kg.
If you want something slightly stiffer than the M1LD, then go for the Model2 Medium distance. This was the first monofin I bought, and I was very happy with it for months, until I got the M1LD, which suited me better (softer).
The M2MD is noticably stiffer than the M1LD (in my opinion) but not overly stiff. It's fine for most depths in freediving, but perhaps not monster depths (>70m). The next one up on the stiffness scale is the M1MD, and that is definitely too stiff in my opinion.

Give the M2MD a go, I think it would be about right for you...

Dolphins, sharks, etc don't have whacking great long tails, and nature is usually pretty good at optimizing design...

...but this may again have something to do with compromize between efficiency, speed and manoeverability.

Wasn't Eric F experimenting with some very long and soft monofins?

Probably (maybe) there comes a point in which other factors like drag outweigh the potential benefits of a longer fin.



We're loking through the long tales. How to handle them?!
Model 1 in fact the biggest for the human being that can be effectively handled. Some exeptions may be, of course, for the descendant of monsters. :)
Theoretically if you about 2 m tall and 250 pounds then you may get some bigger. We can make custom blade for you then.

Width is much more important. But 70 cm in fact is a limit for humans.
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