Truefin Technical
Learn more about the innovation⬇️
Truefin has developed a revolutionary fin for Scuba, Snorkeling, and Spearfishing. It has the comfort and easy kicking of a highly flexible fin, while also having the high thrust of the stiffest technical fin.
Sales are not possible through this technical web site, clicking ORDER takes you to a direct link of Truefin Swim Fin Model 110 size large at www.truefin.com.
TRUEFIN is not allowed to advertise in most scuba magazines, and TRUEFIN is not allowed to exhibit at most scuba trade shows. This is because at this time Authorized Dealers are not the primary channel of distribution. Currently, the scale of TRUEFIN production would result in a product being prohibitively too expensive to market through Authorized Dealers versus relatively simple to manufacture spineless fins. We hope to increase our manufacturing scale such that TRUEFIN will be able to supply Authorized Dealers in the near future. Note that TRUEFIN has however been allowed to advertise and/or exhibit with some companies such as Divermag.com and ScubaShow.com which do not have the requirement that Truefin be available through Authorized Dealers.
Please note, initial injection mold tooling will only provide a size Large (L) fin, which generally corresponds to men's size 9-13, or women’s size 10-14, depending on the boot used. Please refer to sizing information at the ONLINE MANUAL Production dates for S, M, and XL has not been set. Size Medium development is currently in progress and is the next size to be released.
The heel straps currently provided with Truefin Model 110 size Large are stainless steel spring straps Trident R559 Medium Standard Spring Style Fin Strap with Quick Release Side Tabs (TRIDENT DIVE). The heel strap posts are industry standard (large posts - 20mm flange/13mm post) and accept different styles and brands of common fin straps. Some users may prefer popular brands of bungee strap styles, or alternatively (for example) Trident RPH64 Universal Fin Straps, or ratcheting Trident RP48 fin straps generally available at dive stores throughout the US. NOTE: Spring or bungee style heel straps should not be used when jumping out of helicopters because the heel strap spring may extend causing the foot to move out of the foot pocket, and then the fin will slide up the users calf. The fin will not be lost if this happens. When jumping from relatively high heights use ratcheting straps, and if jumping out of helicopters is an expected activity first contact Truefin for more information and options.
Truefin may also be available at Amazon or Ebay
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Possible Amazon link: Truefin on AMAZON
ABOVE : Real time clip of Truefin flexing during a very slow flutter kick. Truefin has the easy slow kicking of a highly flexibility fin, yet greater thrust than the stiffest technical fin when kicked rapidly. Youtube video of TRUEFIN during night shark diving
ABOVE: Easy kicking with Green spines. Note that Green spines remain straight during the frog power kick. Youtube Video link
General notes regarding kicking with Truefin:
When some users flutter kick Truefin for the first time, they may think they should kick them hard for the spines to engage. That is not true, and the fins may be kicked slow and easy with very good propulsion and with high efficiency. A general suggestion is to kick Truefin slowly at first and notice that the blade angle of attack readily forms, followed by thrust during a slow power kick. Note, it is important to continue your flutter kick range of motion after the angle of attack has occurred, and generally relatively long flutter kicks are more efficient at slow speeds, and shorter flutter kicks are more efficient at higher speeds. Yellow spines are designed for a longer range of leg motion and are easier to kick than Blue or Green spines. If high thrust is needed, then the fin will produce thrust at an ever increasing level, without limit, just depending on how fast you are able to kick. Regarding frog kicking, Truefin is an excellent performer and Green spines provide marginally better frog and dolphin kicking performance than Blue or Yellow spines, and Green spines also allow the user to produce thrust during the return flutter kick if the diver has the strength to do so, because with Green spines the blade remains flat (3D scooping allowed) during the flutter return stroke. For users having difficultly twisting or canting their ankle while trying to present the greatest projected area against the water during the pushing away power phase of a frog kick, asymmetrical blade flex may be set up by installing a Blue spine at the Big toe, and a Green spine at the little toe, and recognize that during this customization of Truefin a right and a left fin will have been created (refer to FINNING). Regarding buoyancy, when Truefin is equipped with a stainless steel spring strap it is slightly negative at only three (3) ounces negative in water, and out of the water Truefin (with a stainless steel spring strap) is around 3.5 pounds.
Special note about frog kicking:
Post #140
https://scubaboard.com/community/threads/truefins.633445/page-15
Regarding the frog kicking technique, timing is maybe one of the most important variables. For example, depending on how fast you do the return frog kick, once you are cocked and ready to push frog kick away, you may want to pause to ensure the blade is flat before you execute the power kick away. It may only take a fraction of a second for the blade to be flat or neutral,, or if you do a slow frog return kick you may not have to pause at all. If you have Green spines installed, once you perform the frog power kick then the blade will remain flat as you are pushing away. ......Also, you may find that most of the thrust occurs during the last half of the frog power kick, which is perhaps contrary to what you are accustomed to because spineless fins will have significant flex during the second half of the power frog kick.
Excuse the image of the pressure gauge and compass dangling. Normally that should be clipped. However, it did give us a sense of the accelerations and velocity of the diver. By the way, these pics were at Waldo Lake in Oregon. A cold high mountain lake,, lake surface at 5,400 feet elevation.
www.TruefinTechnical.com - Quick References:
Thrust and efficiency machine test graph comparisons of nine different models of fins from eight different manufacturers versus Truefin during machine flutter kicking are available at TESTING or downloadable from the drop down menu at INNOVATION/COMPARISONS (PDF). Discussion of thrust and efficiency graphs is at INNOVATION/TESTING
A discussion regarding efficiency losses due to hinged, pivoting, and sharply bent blades versus Truefin’s smooth curve blade flex is available from the drop down menu at INNOVATION/EFFICINCY & GEOMETRY. Split fins and vented fins are also discussed at INNOVATION/EFFICINCY & GEOMETRY
A description of the functional differences of the different colored spines is available toward the bottom of this page, and from the drop down menu at INNOVATION/FINNING at the top and at the bottom of the page
A weight and buoyancy table is available from the drop down menu at OWNERS MANUAL/OWNERS MANUAL (online manual) at the bottom of the page
Endurance and durability test info is available from the drop down menu at INNOVATION/TESTING at the bottom of the page, and at the ARCHIVED BLOG
Truefin Quick Guide - bottom of this HOME page
Some reviews at ARCHIVED BLOG/Survey - Dive Master Questionnaires
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ASK YOURSELF THESE TEN QUESTIONS ABOUT YOUR CURRENT FIN OF CHOICE:
1. The holy grail - Does it have the efficiency of Truefin? Better efficiency results in going further when you snorkel, and having air last longer when you scuba dive. That's a good thing. Truefin has the best efficiency of all fins machine tested, and these were honest tests conducted by a team of engineers, designers, and divers who have honorable reputations.
2. Will your fin blades collapse and have insufficient thrust in an emergency situation when kicking intensity is extreme? Truefin won't. According to Truefin machine tests, as a blade collapses or 'goes flat' with spineless fins you get only marginal additional thrust by kicking faster. With Truefin the thrust increases in a linear manner and without limit, and just depends on how fast the user can kick the fins. Also, Truefin generally has the highest thrust at all kicking frequencies.
3. Do your fins have high side rails so you can do reverse and helecopter turns? Truefin does.
4. Are your fins under 24 inches long (size large) to improve maneuverability and reduce the moment of force on your knees? Truefin’s overall length (of size large) is 23.4 inches.
5. Does the temperature of the water effect the stiffness of your fins? The water temperature does not effect the articulating spines or blade flex of Truefin.
6. Do your fins wobble or twist when kicking in current? The spines of Truefin eliminates this tendency.
7. Can you customize your fins for easy flutter kicking, or maximum frog kick glides? You can with Truefin.
8. Are your foot pockets comfortable? No square pockets with Truefin, and the platform of the pocket has an extended heel support region to minimize stress at the medial foot arch.
9. Can you pack your fins in an airport carry on bag? After removing the spines, you can fold Truefin.
10. Do your fins have a limited lifetime guarantee? Truefin does this with confidence.
Few people know about Truefin ®, and that's ok because we are new. We may be new to the fin industry, but we are not new to creative engineered solutions, and making the best performing scuba, snorkel, or spearfishing fin is all we want to do. This industry is full of hype, but the questions above are direct questions that have simple factual answers. To some, the answers to the above questions are not that important, and if you just want to dilly-dally around in the water, plastic fantastic fins are fine and can absolutely be great fun, but if you are serious about finning, nothing kicks like a Truefin.
BELOW: Boat equipped for sea urchin diving
BELOW: Snorkeling in Hawaii
Efficient by Design
Nothing Kicks Like a TRUEFIN ® …. Truefin’s flexible blade in combination with the artificial spines which enforce a laminar flow smooth curve blade flex (no sharp bend, hinge, or pivot of the blade which causes power losses due to flow separation) are perfect for scuba and snorkeling activities due to the overall power and efficiency they provide the diver. Extend your time and distance underwater.
Being highly maneuverable, Truefin® is also ideal for spearfishing. The artificial spines (glass filled nylon) prevent the blade from collapsing during shore diving and provides fast acceleration when in surf, in rough seas with big swells, and in currents around reefs. Open heel design, booties generally required. Sixty (60) day no questions asked return policy, limited lifetime warranty. Made in the USA.
Engineered for Comfort
The foot pocket is supported by a 'U' shaped overmolded chassis (glass filled polypropylene) which receives the removable artificial spines. The chassis transmits the bending moment from the base of the spines to an extended rigid platform. This maximizes engagement without foot pocket distortion, and the extended heel support reduces stress at the medial arch of the diver’s foot while kicking. The upper surface of the foot pocket is made from a tapered thin wall of flexible Monprene® (Shore 72A) to maximize comfort at the top of the diver’s foot (instep).
This is the technical site for Truefin. Please visit www.truefin.com for general consumer information.
Sixty day no questions asked return policy
Limited lifetime warranty
Truefin® has the comfort and easy kicking of a highly flexible fin, while also having higher thrust than the stiffest technical fin. Also, as inferred from Truefin machine tests , which included representative samples of fins having different characteristics, Truefin is the most efficient fin on the market - which enables greater finning distance underwater with a given amount of air.
For flutter kicking, soft flexible fins are designed for low thrust and easy kicking. Stiff technical fins are designed for high thrust but are strenuous to kick at high speed. Truefin is designed to require very little effort at low speed, yet provide high thrust and high speed when kicked aggressively.
In a new approach to mimic nature, Truefin has modular spines which lock into the fin and limit the flexibility of the blade to an optimum ‘angle of attack’ at all flutter kicking frequencies for unparalleled efficiency and power over spineless swim fins. Green spines flutter kick similar to Blue spines, however during the pushing away power frog kick phase Green spines remain perfectly straight.
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Truefin provides exceptional frog kicking glide distances when Green spines are installed.
Truefin is manufactured and assembled in the USA with premium materials and tested over 1,000,000 kick cycles.
Detailed Features
Optimum Performance
Highly maneuverable with overall length of 23.4"
Optimum angle of attack at all kicking speeds
Angle of attack is enforced during all kicking speeds by high tensile strength modular glass filled nylon articulating spines
Highly flexible Monprene® blade for efficiency and ease of kicking during low speed
Blade flex profile is equally distributed along the entire length of the blade in order to maximize laminar flow - no sharp bend or pivoting of the blade which causes efficiency losses due to separated flow or turbulence
Lunate tail sheds vortex rings of approximately circular shape which carry a large amount of momentum in relation to their energy
Streamlined top planar surface of fin above the foot pocket facilitates laminar steady flow onto the blade entrance region during power flutter and dolphin kicks
High side rails channel water during kick strokes and enable reverse and helicopter kicking
3D blade scooping due to lateral articulation of the artificial spines
Blade flex is not affected by water temperature; traditional fins get stiffer in cold water
Less blade wobble and fin twist (less sideslip, straight tracking) during the kick stroke due to rigid enforcement of the predetermined blade flex angle at both right and left artificial spines
Comfortable Fit
Industry standard heel strap posts accept different styles and brands of common fin straps
Low profile non-skid foot pocket bottom sole
Soft tapered edge of foot pocket upper wall ensures comfortable fit at the top of the user's foot (instep' of the user’s foot)
Bottom of foot pocket, including an extended heel region, is supported by an overmolded rigid chassis to reduce stress of medial arch of foot
Durable Construction
Fin is 100% non-metallic eliminating corrosion issues (Monprene, glass filled nylon, and glass filled polypropylene are utilized)
Machine endurance tested in water to over 1,000,000 kicks without failure
Total weight per fin including spines and excluding heel straps 3.1 pounds. Negative buoyancy -0.5 ounces per fin excluding heel straps in salt water.
Manufactured and assembled in the USA with premium materials
Limited lifetime warranty
Customizable Experience
Modular spines may be removed and disassembled, and fins bent in a 'U' shape lengthwise in half during transport to minimize luggage volume
Customize - For advanced users, pick Blue, Green, or Yellow spines depending on the different preferred ‘angle of attack’ geometries. Blue ‘412 spines articulate 60° 'toe down' and 20° 'toe up', Green '012 spines articulate 60° 'toe down' and 0° 'toe up', and Yellow '415 spines articulate 75° 'toe down' and 0° 'toe up'. In some instances asymmetrical blade flex may be preferred in order to facilitate canted frog kicks for those having difficulty twisting their ankle during frog kicking, however note that asymmetrical configurations creates a right and a left fin.
- - - - - - - Blue spines are currently considered appropriate for overall use. Green spines enable the same toe down blade flex as fins equipped with Blue spines during the flutter power kick, but Green spines do not allow the fin blade to flex in the toe up direction during the 'pushing away' power phase while frog and dolphin kicking. Yellow spines have the same toe up geometry as blue spines, yet enables more blade flex during the toe down flutter power kick than fins equipped with Blue or Green spines for an easier kicking experience and work marginally better for users who have a very long power flutter kick.
Model 110
With SPINEFORCE ® - Efficient by design
Ready for a new experience in diving? Learn more about what is currently in production and what will be available in the future.
Want to dive in deep and learn more about Truefin?
TRUEFIN Quick Guide
TRUEFIN has been designed to provide you with the best finning experience available. In order to maintain its high performance, please consider the following instructions to keep your fins in optimal condition.
Care and Maintenance
⦁ Avoid exposure to flame or excessive heat. Continuous and direct exposure to the hot sun is not a problem.
⦁ Store fins flat - If fins are stored in a folded configuration, after unfolding and installing the spines, Truefin may be used immediately without loss of performance, and it will readily seek the original ‘as molded’ shape upon kicking. If it is desired to accelerate the Monprene relaxation toward the original ‘as molded’ shape, fold Truefin in the opposite direction briefly before installing the spines. When installing spines, always ensure that the hash marks on the spines are adjacent to the hash marks on the fin, and that the tear drops on the spines are adjacent to the tear drops on the fin.
TRUEFIN Model 110 Warranty: Limited Lifetime (excluding heel straps)
Disassembly
If the fins are to be disassembled for customization or for travel, each spine may be removed by pressing both red spring lock pins simultaneously with an included spine removal tool or with two blunt objects such as with a couple pencils and the like, while pushing the end of the spine out with the index finger of the other hand, and withdrawing the spine from the fin rail. Flexing the fin may facilitate this action. A spine removal tool is included with every pair of fins. Early red spring lock pins we able to be pushed directly with the user’s thumb and index finger, but his is practically no longer possible. Although there was never an issue with the red spring lock inadvertently becoming disengaged during use, Truefin decided to increase the strength of the red spring lock.
To reassemble standard configuration fins, ensure the three hash marks (III) at each vertebra are orientated down toward the platform of the fin (or sole of the users foot) and with the tear drops orientated up as the spine is assembled, and slide spine into the fin rail, and ensure the red lock pins pop out and fully engage with the fin shoulder holes.
Travel Packing
Removal of the spines enables the user to bend Truefin into a 'U' shape when traveling if it is desired to minimize the volume of the shipping package. Once the spines are removed, the spine vertebrae may be separated and packaged as desired. A temporary 'set' may be observed when unfolding or unrolling Truefin from the travel configuration, and the user may wish to flex the 'unspined' fin in the opposite direction to remove this set, although practically such temporary set is of no consequence to operation and the fin will soon relax and restore itself to the original molded shape. Monprene is a very durable material, and during testing Truefin has parked a fully weighted car tire on top of the folded region of the Truefin blade and there was no functional damage. For a video of a truck parked on top of the folded region of Truefin, please visit the Truefin Youtube channel. Direct link: truck tire test
Entering Water with Truefin
When entering from shore, it is suggested to install the fins on the user's feet after the user has entered water at least waist deep, and remove the fins from the user's feet before exiting from shallow water. In order to free the user's hands it is suggested to thread a cord or other flexible member through the heel straps and clip the cord to a 'D' ring secured to a vest or the Buoyancy Control Device (BCD). Alternatively, a wading entry procedure may be performed from a beach or shore, where the user wades out toward the dive site while backwards shuffling feet to avoid stepping on rocks.
Follow standard entry procedures known in the scuba industry, such as back roll or seated entry method when entering off of relatively low platforms, or from ribs or zodiacs.
For all entries off a boat, regardless of the method, ensure the BCD is sufficiently inflated and have the regulator in your mouth and operating, and with at least one hand holding your regulator and mask in place when you strike the water.
For relatively high platforms or decks, giant stride entries may be performed, however a fin may be forced off of a user's foot while the heel strap spring extends and the foot slides out of the flexible foot pocket, although the fin will still be secured to the user's leg as the fin strap slides up the user's calf. If a user typically enters water off of high platforms, the user may wish to minimize the likelihood of a fin slipping off the user's foot by using non-elastic heel straps (ratcheting or universal style).
For experienced divers, when entering water off high platforms, the forward roll method may be performed. This generally involves standing at the edge of a boat deck, while the BCD is sufficiently inflated and regulator in your mouth and operating, and while having one hand on your mask and regulator and your other arm around your other equipment to avoid these from hitting you as you enter the water, and bend completely forward while imagining touching your feet with your fingers, and tucking your head and body into a tight ball while pushing yourself away from the boat with you legs, and while allowing the tank or tank valve region to strike the water first..
When snorkeling, generally all methods may be satisfactory because the user is not burdened with heavy tank(s) and other apparatus weight.
Avoid walking forward through shallow water while wearing fins.
NOTE: Spring or bungee style heel straps should not be used when jumping out of helicopters while wearing Truefin. If this is an expected activity, first contact Truefin for more information.
Spine Replacement
Truefin Model 110 includes: one pair of black fins with four installed blue '412 spines.
Fin and spines have a limited lifetime warranty.
Continued attempts to optimize the artificial vertebra with FEA and injection moldable material are ongoing to produce the highest performing spines at the lowest cost possible. Current spine vertebra are injection molded glass filled 21,000 psi nylon 612. Based upon machine testing as well as real world testing, if the spines have not been previously damaged and if the fins are operated while submerged in water then they are expected to have a service life of at least 1,000,000 kicks or 500 dives (fins and spines have a lifetime guaranty). Refer to: http://www.truefintechnical.com/ - ARCHIVED BLOG/ENDURANCE TESTS and Refer to TESTING - Bench Break Test .
Having said that, it should be pointed out that the user should avoid causing premature failure of the spines by prying or kicking the spine against an immovable object both in water or on land because the spines are made out of plastic and glass of approximately bone hardness. Typically, if a spine is subjected to a load consistent with kicking or prying against an immovable object, the design draft angles of the vertebrae will cause one of the vertebrae to laterally slide out of position while one of the Monprene passcore bands deforms. If this occurs, no damage has occurred and the spine will have to be completely removed, reassembled, and reinstalled. Note that if a spine breaks due to accident or due to some other event, the fin will generally perform as a traditional fin while having a compromised 'angle of attack'.
⚠ WARNING: This product can expose you to chemicals including lead and lead compounds and/or Bisphenol A(BPAs), which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.
⚠ WARNING: CHOKING HAZARD – SMALL PARTS. Not for children under three (3) years of age.
⚠ WARNING: THIS IS NOT A LIFE SAVING DEVICE. Do not leave children unattended while device is in use.
TRUEFIN, PO Box 645, West Linn, Oregon 97068 Made in USA End of TRUEFIN Quick Guide
