Please Tell me That This is a Joke ?

[meesier42]

There are 3 models using Tan Delta. I tried finding out what Tan Delta is.
According to the web site:
Tan Delta Fin Blade: A special Polyurethane, formulated to have the highest rebound, or snap.

I know what silver and gold are. I do not know what this "special" polyurethane is. For all I know, it could just be a shinier version of the default. Then again, it could be as the manufacturer claims and be a special blend that makes fins snappier.

Here is the difference in their advertisement's:
Polyurethane, stiffness 87 / rebound 78
Or: Tan Delta Polyurethane, stiffness 90 / rebound 100

I want to believe, I just require proper evidence. I guess revealing the technical details of tan delta vs their normal polyurethane would entail giving away a competitive advantage. Perhaps they could enlighten on how they test stiffness and rebound?

Yup, you nailed it, the TanDelta material is a proprietary blend of urethane that was developed to meet the specific requirements that the FinDoc set. It not only looks good, but it yieds enough to flex properly to maintain swimming efficiency, but has a very high rebound, which is to say, most of the work you put into flexing it (like streching a spring) will be returned, mechanical efficiency.

As for evidence, well bust out the durometer (you have one don't you) and take some measurements. Then you can do the leading edge segment flex testing that was performed up at Uof Buffalo, and a couple of other test that were described in detail. And then you can try and relate that to fin made of completely different materials, in a completely different shape, that operate on completely different principles and try to draw some conclusions...Or, of course you could just try diving them

 

[mempilot]

FinDoc,

Would you come down to S FL and make me a believer? I'm not talking about wearing a skin and swimming in a pool with FFs. I'm talking about diving in real conditions with real gear configurations. We could do a standard S FL wreck dive on say the Lowrance in our typical current with typical gear loadout. We'll swim forward, rotate, backwards, scull, frog kick, swim the gear up, etc... I'll put away the Jets for the day. How about it? I'm open to the idea if you are.

Eric

 

[montanadivenut]

Ummmm.......I don't really have anything further to say, but just thought I'd add to my number of posts in an attempt to be more "relevant" in the future! I never realized that sheer numbers of posts made someone a good diver......maybe 200 more and I'll be ready for tri-mix!

 

[deco_martini]

Yup, you nailed it, the TanDelta material is a proprietary blend of urethane that was developed to meet the specific requirements that the FinDoc set. It not only looks good, but it yieds enough to flex properly to maintain swimming efficiency, but has a very high rebound, which is to say, most of the work you put into flexing it (like streching a spring) will be returned, mechanical efficiency.

As for evidence, well bust out the durometer (you have one don't you) and take some measurements. Then you can do the leading edge segment flex testing that was performed up at Uof Buffalo, and a couple of other test that were described in detail. And then you can try and relate that to fin made of completely different materials, in a completely different shape, that operate on completely different principles and try to draw some conclusions...Or, of course you could just try diving them

I asked for a link to the updated navy tests. Could you provide one for the UofBuffalo testing? Perhaps scan the tests if they are not online and make them available for peer review?

 

[The Kraken]

A durometer is a gauge designed to test compression.

the K

 

[meesier42]

I asked for a link to the updated navy tests. Could you provide one for the UofBuffalo testing? Perhaps scan the tests if they are not online and make them available for peer review?

I have already provided the link to the new test done at U of Buffallo (see post #116 on this thread), and as already discussed, the 2003 test did not include FF's. If you want the 1993 test, you'll have to do a FOIA request to get it.

A durometer is a gauge designed to test compression.

no, a durometer test measures the hardness, similar to the Rockwell Hardness scale, but much lower values, generally using scales of either Shore A or Shore D. It is a measure of the resistance to deformation. compression is measured with a pressure gauge.

 

[sambolino44]

...And any value if it is perceived to be worth an amount is worth exactly that amount. Now if it is worth that amount to another person that is a different matter. This one specific fin is not for the masses, it is for those who are able and willing to pay that price. If they are, then it is certainly worth it for them. If someone isn't willing to pay the price, then its not worth it...

I disagree, I think. What I mean is, I'm not willing to make the sacrifices in other areas of my life (you know, rent, food...) it would take for me to be able to get a pair of these fins, but I really really really really really really want them. In fact, I need them. Actually, when you consider how my mental well-being has been so negatively impacted by the knowledge that these fins exist and I can't have them, you might say that Fin Dr is harming me by not sending me a pair! And think of how much he'd gain by having me be a roving ambassador of Force Findom. All eight of my friends will see them and... well, maybe this plan ain't so great after all. I still want them fins.

 

[Bob Evans]

Pete, FFs aren't new.

Maybe the $750+ set of fins is equiv. to the $100 hammer. (any government contracts here??)

Anyway, if the FF really is a good tool for people with dehibilitating circumstances like your ankle, and it allows them to dive, then I'm surprised you wouldn't look at like he is taking advantage of you by charging $600 more than the next most expensive fin.

If FinDoc wants to see his fin used by the masses, then his pricing scheme is out of whack. The added value, whether perceived or real, isn't worth an extra $600.

To defend that is almost like, well, defending a sponsor. Hmmmm?

No sponsorship motivation from Force Fin here, but Scubaboard should be commended for sponsoring all of us with their manufacturers' sub forum. Great idea! It gives Force Fin and any other SCUBA equipment supplier the opportunity to openly communicate with board members, and board members a place where they can openly ask us questions directly.

 

[mempilot]

...Scubaboard should be commended for sponsoring all of us with their manufacturers' sub forum. Great idea! It gives Force Fin and any other SCUBA equipment supplier the opportunity to openly communicate with board members, and board members a place where they can openly ask us questions directly.

Agreed.

 

[The Chairman]

Speaking of signing up... Our new registration system is up and running: https://reservations.scubaboard.com/ This is a SECURE Site.