Tropol Monofin - a Fondueset Review

[Fondueset]

Good idea - Lubos seems to talk more about the first - so perhaps we should go that way. I like the second - because it includes the heel - but I won't cry.

I think the material and design of these footpockets is very good - no hot spots or rubbing. But footpockets that are too small make your feet feel like they will explode after awhile.

 

[trux]

I suggest to agree on a type of measurement before we start to discus about angles

I think that the only measurment that is interesting, is putting your fin on, laying back down on a flat surface and letting someone take a photo of your feet and of the fin, while you keep holding your feet strightened but without too much strain (as you would like to do during the glide phase). You then measure the angle of the blade to the horizontal reference, and chose/request a fin with bigger or lower angle, if the current one does not meet the needs and is not paralel wih the surface. Deduce the deformation of the fin due gravitation, of course.

 

[Fondueset]

Okay - heres one Anybody have some software to measure the angle? I think it is just a tad high, because of my heel - but pretty close.

 

[cal]

Hi Trux

I think that the only measurment that is interesting, is putting your fin on, laying back down on a flat surface and letting someone take a photo of your feet and of the fin, while you keep holding your feet strightened but without too much strain (as you would like to do during the glide phase).

This may be a way to find out what angle you needed. I am Talking about to decide which relational system to take to define the "angle" and comunicate to lubos. See the picture!

cheers, Michi

 

[trux]

This may be a way to find out what angle you needed. I am Talking about to decide which relational system to take to define the "angle" and comunicate to lubos. See the picture!

Just that's what I am speaking about, and what is completely irrelevant, because it does not matter how you measure the angle between the footpocket and the blade. The only thing that matters is whether you need a bigger angle or not, and how much bigger. You can then communicate it to Lubos. Now if he then measures it with one or another method, is unimportant as long as he increases it correspondingly.

 

[Kars]

Hi Fonduset,

I measured with a plain transparent triangle of my screen, about 11 degrees between the blade and floor.

But I would recommend having 8 or 9 more, because in the water the blade tents to bent more. Prohibiting not straitening one's legs and hollow backs.

Funny that with an official angle of 19 degrees, heel to toe, adding 11 makes 30

I think it is clear that freedivers have different needs than finswimmers, and it's very kind of Lubos to take the time to discover them and adapt his fin to it.

Thank you Michi and Fondueset for your information on the foot pocket size and blade stiffness, that's very useful information for those ordering a fin, supplying a fin!

Kars

 

[cal]

Okay - heres one Anybody have some software to measure the angle? I think it is just a tad high, because of my heel - but pretty close.

I measured about 9 degree for floor-tip/footpockets and 9.5 degree for floor-footpocket/blade direction at the footpocket (without bend caused by gravity) in my CAD.

 

[jome]

Just for reference, for me the biggest issue about angle is not to have the blade straight for the glide-phase (which is of course a good thing too but for example in cw not 100% must), but to be able to get a good grip and on the back-kick and make an efficient but relaxed back-kick which seems to be essential to keep up a slow but efficient "whale kick". Without a good grip on the water on the back kick, the front kick will become too explosive and opposite in profile as it should be (should be starting slow, accelerating to the end). I don't know if that makes any sense to anyone else, but at least that's the problem I'm stuck with currently. With smaller angle it is still possible to do, but requires very active flexing of the ankles which becomes too much of an effort to pay off in the end.

 

[myfish]

First off, I don't yet own a monofin.

However, it is on the 'to get list'.

One thing common in all the threads i read is 'angles', 'blade stiffness' and 'variance between makers' etc..

Why do we need a fixed blade angle ?

IF ? individual fins are so disalike in feel and performance then surely the only way to accomodate a new fin is to either like it, acclimatise or change it.

That cannot be good and its both money and training time out the window.
A fin angle i like now i might not like so much after 6 months with it etc.

Why not use a series of hard, non compressable shallow angled shims between footpocket and blade ?
Is this possible.

If you had shims on BOTH sides, upper and lower sides you could in effect move several degree's either side of a neutral fin angle. Lets suggest neutral angle of 15 deg with 7 deg of adjustable shimming either side.
thats obviously 8 deg thru 22 and would be more likely to accomodate individual needs or perhaps i'm way off target here making it too complex.

 

[Fondueset]

Interesting, Myfish. I'm sure that would be doable - particularly with something like the C4 footpocket - that uses screws. You could just use shaped shims with screw holes.

Everybody - I've been emailing the gist of this thread to Lubos - I think he is inclined to make a freediving fin with a 25 degree angle - - that is adding 10 degrees to the current angle.

Its important to note that these footpockets are molded - not hand-made. So the trick is to find a happy medium angle-wise that will make the most people happy.

 

[trux]

I've been already speaking about a variable angle with Lubos previously. Normally, monofin manufacturers do not really consider such possibility, because not only it is not really so important at finswimming, but finswimming rules forbid any mechanism in fins. Same with CMAS rules for (AIDA) freediving. So Lubos knows now that at the freediving fin it might be acceptable, but still thinks that developing, tweaking, and testing such fin would take much more effort than simply casting a new footpocket. Hopefully we'll see in future such fin, but probably not in short term.

 

[myfish]

Ah well, at least its nice to know that people have considered this area of design.

As a first time shopper for a monofin its a case of what angle for CW and what angle for Dyn.

Then, a soft Vee for Dyn as opposed to a nice stiffer blade for getting moving quickly off the plate.

So in reality, this is twice the pain in finding a fin as trying to compromise will see most buying 3 fins in quick succession i think.

Anyway, i think i'd rather learn monofin in the pool first so i'll probably have more idea of what i'd need to carry over into a constant weight fin especially fin angle wise.

 

[Kars]

Considering the difference in angle for CWT and DYN:

In general in Constant Weight people have a continuous stroke, thus less disadvantage having less or no blade angle, though in the glide phase the increased hydrodynamic speed is substantial factor, increasing almost linear with increasing depths.

To Dynamic a bigger angle is relatively more beneficial, especially when one uses the popular "Kick 'n glide" or the latest Molchanov "kick kick 'n glide".

My relative soft fin works also at depth, but I notice I need to pay attention to having a reasonable good technique staying in the fin's 'efficient zone' avoiding overpowering the fin with blunt force. (treat her like a lady, firm but gentle) Note that I dive with a 3mm suit and without any weights.

So my fin is at the moment suitable for both my CWT (65m) and DYN (134), and I love her very much

Maybe you're going to be Tropol's first new 25 degree fin owner! - With the footpocket and blade tips mentioned above I would know what to order

Kars

 

[myfish]

thanks, this thread has started to clarify my needs and reading about the fin development is great.

far better than buying blind.

 

[jome]

According to Lubos the first prototype of the 25 degree angle would be ready earliest in the beginning of next year...

I'm still going to take the leap of faith. If it sucks (and I'm sure it won't suck based on fondues comments), well, can't be much worse than most monofins I've owned. If it rocks, I'll buy a 25 degree one for sure and use the m4 as a training fin...

 

[jome]

Finally received my Tropol. After a quick and incoherent testing session at the pool, here are some observations.

Negative:
-Foot pocket is too narrow for my feet, hurts like hell (fin is supposedly sizer 45, which is also my foot size, but I guess I have wide feet). In general this is where most fin manufacturers "miss". There is no reason performance wise to have the fin so thight at that "widest part of the foot", it just creates agony.
-There is no hole on the foot pocket for letting water out, so it's kind of hard to get the foot fully in there. But that's easy to fix.

Positive:
-Build quality seems good. Ok it looks a little rough, at least in plain white, but feels solid and the lack of too many glue-seams is appealing
-Angle is better than I feared (more than my current fin), but I could use more
-Overall action is pretty good. I like the little supports on the footpocket that keep the foot part very rigid and the bending is on the blade. On quick testing I lost 1 kick per 25m lap, which is pretty good, but at the same time, it was a little harder to swim with physically.
-Blade seems to be "medium+" (I ordered 400-800m in finswimming terms), my old one is much, much softer, but I think this stiffness suits me better, but it's really stiff for a "long distance" blade IMO. I would be hesitant to recommend any diver a stiffer blade unless they are very, very sure that they want a super stiff blade.
-Despite being very negatively buoyant it felt ok for dynamic (which is not what I was after, but it's a nice bonus).

All in all, I'd say it's a pretty good fin. Not revolutional in performance sense but works as well as any average non-axial fin. Time will tell if the build type/quality proves to be revolutional (in terms of falling a part which is a common problem for monofins).

With a little more angle and wider foot pocket on the critical part, I'd even go as far as to recommend it. But now I'm forced to say that pay close attention to your foot size especially if you have wider than average foot.

 

[Fondueset]

Simo, It may be you have more experience with different monofins than I, but every hyper - style fin I've tried has really tight footpockets - for width (maybe my feet are wide too).

I have been thinking this is because they were originally sized for finswimming - which requires very tight pockets for power transmission due to hard kicking and which also involves swimming for relatively brief periods of time. I wear 44-45 normally - so I ordered the biggest size they have (45-46) - which is amazingly comfortable for me. Even my super big sized hyper fin is not this comfortable.

Lubos also told me this fin works a little differently from others - I am not sure what exactly he meant by that - but he said I should give it a few weeks. Other than it being stiffer than my other fins I am not sure exactly.

Anyway - if you can post pictures it would be great. Also keep putting your impression up - I will pass them on to Lubos and maybe use them in an article I am writing if its okay with you. Right now I think I might suggest that he add a larger size for people with big or wide feet - and for those who want to use thick socks.

- So far my fin shows no signs of falling apart!

 

[jome]

Yeah I'll post some pictures later today.

My current fin is actually custom made to have wider than normal footpocket. Maybe I'm just used to too comfortable

 

[jome]

Ok, here's some further details (too much, I'm afraid

On the first picture you can see my ugly foot and illustrated in red the painspots.

4th picture is "foot on fin" illustrating the problem. The foot is way too much wider than the footpocket.

2&3 are a non-scientific measure of both, as you can see, my old fins footpocket is almost 2 cm wider. The inner measure may differ, but the point is, that's quite a difference.

My biggest complaint (to virtually all fin makers) is, why not make the "red part" a little bit wider? For example the tropol footpocket is a completely straight rectangle, while my foot obviously is not.

In defence of the Tropol, in vertical sense the foot pocket is very nicely formed. There heel support is a little different than I've seen, but i like it (there is a kind of a really steep incline on the very end of the footpocket, hard to get a good picture.

Also, the foot pocket as a whole is slightly angled against the blade, where as in the hyper it is opposite. In "net angle", this contributes to the Tropol having a bigger angle and better "grip" on the water on the up kick, which I was after, so that is good.

 

[Fondueset]

I know a diver who has huge feet and used shoe stretchers to widen his Omer footpockets I wonder if that would work on the Tropol. (I would email and ask before doing!!)

I just measured my foot and fin - with weight on my foot it is about 11-12 cm wide (nearly 12 between the two points you've circled)- the tropol pocket is 10cm wide - outside dimension - so probably only 9 or so inside. But my feet are quite comfy even with 3 mil socks.

Possibly it's the past couple of years swimming in my tighter fitting Ukrainian fins. At first I had to wait 5 or ten minutes before I could walk after swimming - then gradually I got so I could wear the larger one for up to six hours - the smaller one an hour is pushing it. I found that the pain would peak at 20 minutes or so - then almost completely go away with my larger fin.