Fins and manoeuvrability

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Gotcha didn't see the post. Wasn't accusing you of anything. And to be honest, I know my 10k bike is stamped out at a factory for a fraction of the cost. (I own a company that gets everything made over seas, you'd be surprised with what you can get made for limited runs)

I'm sure they are great fins maybe I'd like to try a pair. Although at the current price level just more than I'm willing to spend currently. As a small business I wish them well for sure.

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I don't know where in FL you live - but Dan Volker lives on the east coast and he is always happy to loan fins to people who want to try them.

My understanding is that Force Fins tried out sourcing some production several years ago and did not have good results with the resulting quality. This was the standard Force Fin urethane which is much easier to work with. So I doubt Bob would want to try it again since he has recently moved most of the production to a facility in PA (they used to do a small amount of work for Force Fins but have now expanded to handle the production of fins made from the Original and Pro urethanes). Current intentions are to open a small facility in CA where Bob can directly oversee the production of the High $$ fins himself and continue the development of new concepts.

Force Fins is a small business - producing a few thousand fins for recreational divers and the military (US and others) - the High $$ fins were only about 2% of the volume. Out sourcing 60-100 units per year is really not feasible.
 
TN if you cant answer any of my questions just please say "I don't know, I made it all up." I am trying to get real information here to shed light on things.
 
As a racing mountain biker, a sub 1k bike should be given to your children or spent on a used road bike or a fixie / beach cruiser for your lady friend.

As a guy who owns a 10k full carbon bike, well 2 of them road and mtb I'll admit the diminishing marginal utility comes in quick after 3-4k just like spending 1-200 on fins.

I don't think the cycling comparison is accurate. I won't pay 500 for fins. 130 for jetfins is enough. If i want to go really fast I'll use my free diving fins.

I'm sure the quality of the product is good, but the cost could be lowered with better sourcing or getting them made over seas.

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OK...True story... some years back Sandra and I went to Italy for a cycling vacation....I brought a $6000 Stork that the bike shop I frequent in Lake Worth, claimed was the ultimate....Unfortunately, I had few times to ride it prior to the trip....So once in Itally, I found it was making climbing the mountains harder than they should be for the grade....and on the donwhills I like to fly on, it turned like a truck..you had to carefully plan your line well before the turn started for these huge mountain switchbacks, and then STAY carefully on this line, not deviating, if you were anywhere near high speed ( 30 to 50 mph)...On the 4th day we were there, we stopped at a cool looking bike shop at the foot of one of the great climbs up a mountain....they were a Pinarella dealer. They had a nice Pinarello Prince to demo...so I took it and rode it up the mountain, and then down....In America, the way it was set up, this would have been about a $9000 or more bike, but in Itally more like 6k...
On the climbs, it was like I had a big hand, shoving me forward with each pedal stroke....the frame was not wasting energy like the Stork.
On the awesome downhills, this Pinarello was more like a Lamborghini.....you could be anywhere in the arc of the turn, decide on a different line, and the bike would already be taking it, and easily optimizing the new line.
So the Stork became junk I had to sell, and the Pinarello was the bike I rode for the rest of the trip.
Point being....Like with fins, bikes have brands that cost plenty, and that really stink....and there are bike brands that cost a bit more, and eclipse most other bikes no matter what they cost...though these are not "cheap".
I also have a Specialized S Works Mountain bike, full carbon as you know, and very light....And the mountain bike I had prior to this was a Trek Liquid....I think the Liquid was about 3k....and I absolutely believe the S Works Specialized is way more than twice as good a bike as the piece of dung Trek Liquid!!! Technology....For non-cyclists, the geometry of the bike frame, and the choice in materials for each part of the frame..where it is stiff--where it is compliant, these make a huge big difference on how well you can leverage your power on sprints or climbs...and the whole geometry issue is huge on cornering and descending mountain switchbacks...This is why I was using the cycling analogy.
 
"Exactly" what causes the inability to mass produce these fins with this mystery compound? Sounds very far fetched to me. What exactly is done by hand? Fin strap attachment? I doubt they are hand shaped like a surfboard blank. If there are molds, which I suspect there are, they can be mass produced.
I'm told urethane molding is neither cheap nor really suitable for mass-production. If you're mixing small batches because the material hardens too fast, you're looking at hand-pouring. If you're hand-pouring, you pretty much do hand-trimming and finishing as well. Not that any of it is my problem as the consumer: my problem is they aren't paying me enough.
 
Again, Tan Delta is not a material regardless of what Force Fin calls their compound. It is a term used for vibration dampening purposes. You are confused again.

---------- Post added September 28th, 2015 at 02:24 PM ----------

"Exactly" what causes the inability to mass produce these fins with this mystery compound? Sounds very far fetched to me. What exactly is done by hand? Fin strap attachment? I doubt they are hand shaped like a surfboard blank. If there are molds, which I suspect there are, they can be mass produced.

The term "Tan Delta", although not scientifically properly applied, is used to describe a high grade urethane compound that has a very low energy loss - returning significantly more of the energy put into it during the power stroke than other urethanes. I realize that the most common use of "Tan Delta" has to do with electronics - but Force Fins has used the term to describe this material long before I ever heard of Force Fins. If you want to quibble about the correct usage of the term - that is a red herring and has nothing to do with fin performance.

The molds that are used for making these fins are all hand made - they are designed for hand pouring of the urethane mix. To remake the molds for mass production by machine would be a major undertaking that the volume of business probably would not support. I have offered to do a 3D Laser scan of the fins/molds for Bob, so that CAD files can be produced which might allow for redesign of the molds for machine operation.

The fins are all hand trimmed and buffed by hand (high polish on the "Tan Delta" fins). Then straps are added by hand (standard or bungies). So currently there is lots of hand work. Could it be automated - probably if Force Fins produced 100K fins per year, it would be possible. But for less than 5000 fins per year, probably does not make sense.

The "Tan Delta" urethanes are very quick setting and really are not suitable for mass production. It would cost a fortune to set up a RIM (Reaction Injection Molding) operation to work with this material - definitely not cost effective unless they were being produced by the thousands (and the cost of the material would still make the price of the fins several hundred dollars).

I have lots of empathy for Bob and Force Fins having started and sold 2 "small" businesses (because I did not want to take on partners to reach the next level) and I am currently working on my third with my wife. We run a 75 person engineering and design firm specializing in working with process industries. I have over 50 years in the chemical and consulting engineering business - so I fully understand Force Fins problems/situation. if you have not been an entrepreneur, I doubt you can fully understand the problems - it is easy to quote things you heard in business school classes - it is much different in the "real" world.
 
So now we have an answer. They are just fins that are molded with a compound like most others, the monkey work is done by hand, and sales do not warrant or support mass production. Case seems closed other than a tryout if FF supports it. Trimming leftover molding flash does not constitute "hand made."
 
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So now we have an answer. They are just fins that are molded with a compound like most others, the monkey work is done by hand, and sales do not warrant or support mass production. Case seems closed other than a tryout of FF supports it. Trimming leftover molding flash does not constitute "hand made."

Yikes...if this was a real life coffee shop discussion between you and Tenn Traveler, one of us would have to be getting between the two of you about now.... :)
Let's try a different path...

The truth about how these fins perform, is all that both YOU and the Traveler, care about.

Rather than this becoming Global ThermoNuclear War....How about I intercede with an better way to settle this...

I will get you 2 comped boat trips, minimum, in Boynton or Riviera Beach...places where the "Test Track" is ideal for you,
I will get you the fins to use for free also.
I will get you best Diver rates at any hotel you want.

You just agree to do this, and then "Demo" the Excellerating Force Fins.
If after doing this, you are inclined to agree with me, then all you will be asked to do is to post this....You don't even need to say anything to your nemesis :"-)
If you think the Excellerating FF's are not up to what I posted, then please post that.
What do you think?
 
Do you have a reading comprehension problem????

They are hand poured, hand trimmed, hand polished and hand assembled - is this not hand made??

And if you had any knowledge of how most current fins are made - they are mostly injection molded plastic with, in some cases, some rubber. Probably less than $2 in material cost. Now there are a few fins out there that are molded all rubber - but they are normally higher priced (i.e. Bio Fins).

You just earned a spot on my ignore list!!!! So forget any future responses!!!
 
The "Tan Delta" urethanes are very quick setting and really are not suitable for mass production. It would cost a fortune to set up a RIM (Reaction Injection Molding) operation to work with this material - definitely not cost effective unless they were being produced by the thousands (and the cost of the material would still make the price of the fins several hundred dollars).

Atomic sells fins that cost $260.

If the FF TD fins are that good, why wouldn't they sell in the thousands? IOW, if they are so superior to all these other (expensive) fins on the market, it seems like the business case would easily support the investment to mass produce them - taking what they sell for now as a baseline for guesstimating how much less they could be sold for when mass produced. Heck, just listening to you guys talk has almost got me thinking I'd be willing to spend $400 on fins. Almost.
 

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