Question Truefins

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Interesting...
But as a finned swimming instructor I had said to both divers that they flex too much their knees and the one more far away is kicking too fast.
The closest one is keeping arms in wrong position (not fully extended) causing significant drag.
The fins seem to behave properly...
Angelo, you don't know how much fun I'm going have to tell those divers about 'my' observations as to why they are lousy swimmers.

Best regards,
Joe
 
...I'm am going to try to find out what ship this was...
I haven't been to Wreck Alley since 2012.

This is the Ruby E, 165 foot Coast Guard Cutter. Upright at about 85 feet since late 1980s

The Yukon is also in Wreck Alley, a 366 foot Canadian Destroyer Escort on its port side at about 105 feet since 2000.
 
I haven't been to Wreck Alley since 2012.

This is the Ruby E, 165 foot Coast Guard Cutter. Upright at about 85 feet since late 1980s

The Yukon is also in Wreck Alley, a 366 foot Canadian Destroyer Escort on its port side at about 105 feet since 2000.
Thank you for this information. .. So that is what 40 years growth of barnacles looks like.

By the way, I guess I stand corrected. When referring to sunken ships I guess proper etiquette is to say it is the Ruby E.,,, versus was the Ruby E.
 
Ruby E began as the Cyane (WPC-105) to enforce prohibition. In the 1950s it became the Can Am, a fish processing ship. It became the Ruby E when is was sunk as an artificial reef in 1989.

It is mostly covered by Strawberry anemones, giving it great color and texture.

See the very interesting thread Ruby E Photogrammetry Model (including engine room)

I return the thread to its intended topic, Truefins
 
....I also like the visibility provided by those white dots on the sides.

The white dots are the portions of the substrate (rigid over-molded chassis) that are coincident with the outer surface of the platform. By having a number of substrate surfaces coincident at the inside and outside of the platform or sole, and also coincident at the sides of the the foot pocket, then the substrate will be properly centered before the Monprene is injected. We could use any color for the substrate of course because it is just molded with glass filled polypropylene, but we chose white for visibility. I guess you could also color balance a camera with the white dots while under water if need be. ... With this fin, a rigid substrate is required to transmit the moment at the base of the spines during kicking to the foot platform, without which the foot pocket would distort unacceptably.
 
Ruby E began as the Cyane (WPC-105) to enforce prohibition. In the 1950s it became the Can Am, a fish processing ship. It became the Ruby E when is was sunk as an artificial reef in 1989.

It is mostly covered by Strawberry anemones, giving it great color and texture.

See the very interesting thread Ruby E Photogrammetry Model (including engine room)

I return the thread to its intended topic, Truefins
Did you get a chance to dive your fins yet?
 
Did you get a chance to dive your fins yet?
No, not yet. I went down to Colombia and dived off Malpelo from July 19-31, not the trip to take a 2nd pair of fins to try them out.

I will be back down in Florida in Sept for a week or 10 days and plan on alternating them every other dive to get a good idea of how they compare to my XTs. They came with the blue spines installed, I will likely try those out on the first go around. I do a fair amount of frog kicking and will give the green spines a trial the next time.

The Truefins are quite heavy, looks like about 7.1 lbs per pair. The XTs are no lightweight at about 5.8 lbs. The Truefins are only slightly negative, the XTs are too.

The fins are not obviously very different in size
1692297169027.png
1692297187689.png


I'm looking forward to my fin test. I usually dive by myself, maybe I could get you to shoot a video :)
 
Just a note to the viewers that those blue substrate fins were a factory color error, and that inventory is currently not being sold. The normal production for Truefin is with a white substrate.
 
So now it is white, green and yellow?
The normal production fin is black Monprene and only a white substrate available.

The spines are independent considerations, and we will continue with Blue for universal applications, Yellow for easiest kicking (more angle of attack during flutter kick), and Green is optimized for frog kicking where Green spines stay flat when pushing away power frog kick. Green spines and Blue spines have the same angle of attack during the flutter power kick. ...Blue and Green spines have a sixty degree flutter power angle of attack, and Yellow spines have a seventy five degree flutter power angle of attack.

None of this matters to most people, and Blue spines are fine for all applications. ..This gets kind of complicated to explain, but another reason Blue spines are standard is because for asymmetrical blade flex, you can put a Blue spine at your big toe, and a Green spine at your little toe to reduce the cant or twist at your ankle required during an efficient frog kick. If users purchase Truefin with Yellow spines, then they have an orphaned product in that it is generally not suggested to mix Yellow spines with Green spines because they have different flutter angle of attacks, and you may not kick parallel during the flutter power kick..

As I say, it's all kind of complicated to explain, but there are benefits if a user really wants to get into it and tune the fin to their particular kicking style. Unexpectedly, we have had more than one user that preferred mixing Yellow spines with Green spines despite our recommendation to only mix Blue spines with Green spines, and they wanted their legs to be biased non parallel during flutter kicking (if legs are to be biased apart during power flutter kick, install Yellow spine at big toe or inside rail, and Green or Blue spine at outside rail) ,,, so it is impossible to suggest how to fine tune a fin to a specific user,,,, so we just say start with Blue spines and see if you really need to tune the fin to be optimized for your exact preference. One thing about product development is if you give users too many choices, too much confusion is created, but divers are an exception because divers are technically orientated, so we will offer a way for them to customize the fin if they choose.
 
https://www.shearwater.com/products/swift/

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