Beiträge von Dr. Zak

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    It may be little difficult for a beginner to use 100cm mast in waters less then 100 cm deep. When tide is high in my location I use a longer mast. But I still need to walk for long way in water in order to start at enough depth.

    The most popular windsurfing and kite spots in the USA are very shallow. Sometimes it gets under 50 cm deep for miles. You do not see any foilers there but the spot are very nice. With shorter mast it makes it possible to foil on these popular spots. This is the reason why two legged design could be an advantage because it makes it possible to spread the main wing and the stabilizer at a grater distance for significant stability increase. You may want more stability with shorter mast in order to hold your altitude more precise. Longer fuselage adds stability too but at a higher cost of drag: more total area of parts under water. Also, long fuselage becomes too flexible as you can see on this video:

    I personalty find it much better to foil on a stiff design.

    Besides, you need a wider board for a longer mast. Wider boards are popular anywhere but not in the US. In my area we ride 70-90 liter boards. I think it is because you can start it easy anywhere on under 1 meter deep water. Water start is often easy because we have winds and warm waters almost year round. Smaller boards fit into a regular small size car. 100cm mast does not work on my 60cm wide board. 50 cm mast work well on my 60cm width board.

    When I go windsurfing I take foil as a backup to use it if I do not have enough wind. If I used 100cm mast I would need to bring a wide board. Wide board does not fin inside my car so I have to put it on the top of my car and I need to watch it so it does not explode from air pressure getting hot under sunlight. Even when I am lucky to have enough water depth for 100 cm there is sea grass on the bottom. Shorter mast does not get as mush sea grass as 100 cm.

    In my practical windsurfing routine the only reason when I want a longer mast is when I go to another spot like ocean or open bay where we often have waves. But I still like 75 cm mast more compare to 100 mast.

    I agree that all the designs have advantages and disadvantages that can be discussed theoretically. However, when it comes to practical every day using of different designs you find out that the every day conveniences may dominate over the theoretical conclusions in front of the computer screen at home.

    Wir verwenden einige Kevlar-Fasern aus technischen Gründen. Aber manche Leute finden es gut aussehend.

    Ich würde gerne wissen, warum Sie denken, dass Kevlar-Fasern an Kompression arbeiten? Kevlarfasern befinden sich in der neutralen Zone des Abschnitts - keine Kompression, keine Spannung. Die einzige Spannung auf Kevlar ist von der Spannung des Bolzens. Der Vorteil von Kevlar ist, dass Sie die Finne nicht verlieren, wenn Sie mit etwas kollidieren. Beachten Sie, Kevlar-Fasern sind um die Tonnenmutter gewickelt. Fragen Sie Wolfgang, wie er Laufmuttern an seinen Flossen montiert. Ich nehme an, Worfgand bohrt Fols. Bohren von Löchern schneidet Fasern. FRPGear wickelt Fasern um die Laufmuttern - dies ist eine wesentlich stärkere Integration der Laufmutter.

    Wenn Sie über Kompression oder Spannung sprechen möchten, müssen Sie über die Fasern auf der Seitenfläche der Flosse mit der maximalen Dicke sprechen. Diese spezielle Flosse hat unidirektionales S-Glas auf Kompressions- und Spannungszonen.

    Wir haben bereits den Ground-effekt auf das russische Forum vor langer Zeit abgedeckt.

    Ich habe auch einen Bezug auf den Ground-effekt dieses Videos.

    Ground-Effekt ist einer der Gründe, warum TheVirus und Wolfgang Design nicht so effizient wie Frpgear Design ist. Müssen die maximale Distanz zwischen der Saugseite der Folie und dem Boden (Wasser oder Unterseite der Platte) halt.

    Ja, Ground_Effekt hilft und es ist kein Geheimnis.

    But anyway, as kleppy wrote, both concepts will work to some extent and that is enough knowledge for me right now ;)

    Indeed, this is enough to explain that the back of the board does not continue to elevate when speed increases.

    It was actually one of the secrets that the angle of attack may be positive or negative while it seems to be logical to have it positive for someone who has never used this toy. When you think more about it you find other discrepancies in the proposed document: stabilization. Since we now know the secret about smart angle of attack the obvious conclusion is that it may be acting as a horizontal stabilizer. Indeed, it is nearly impossible to think about it without testing the actual part. But when you are using the actual part on your board you can feel stabilization very well compare to a traditional fin particularly on waves and at high speed.

    The conclusion from this partial intellectual property disclosure is following:

    fly-fins are not only helping to get on planing but also add stability.

    I can assure you that there are other details that we have not discussed yet because the manufacturers did not disclose them yet. But for most of the consumers it is enough to say that you can go faster because the hydrofoil unloads the board and the board does not know that you are so heavy.

    If you read this conversation from the beginning you can find a concept that was made in Germany by Wolfgang. It has been a strong believe of the participants that the foil needs to be under the center of gravity while the manufacturers and the real users suggested opposite. Now, when we finally know one of the key secrets with the angle we can explain why placing the foil under the center of the gravity may not be as beneficial as the manufacturers in the US and Poland produce. Since the angle of attack may be negative forward located foil will suck the board into water and increase drag. Stabilization will not work either. This is the reason why I have been asking for the test result on the fly-fin concept from Wolfgang and we do not see it. I assume it may not work as expected.

    When more competition gets involved into this we will be disclosing more design secrets that ordinary people do not see yet. This practice is normal because of competition. Because you do not know all the key detail it may be looking unreal (too good to be real) when you watch the units in action and you cannot explain the reasons of the performance so you start trolling on poor skill of the novice sailor.

    In addition to the other secret phenomena that we. the manufacturers, alredy know there are some phenomena that are still under research. This is good because it means that we will possibly have new discoveries for more improvement.

    The most interesting and astonishing one is the wing set at a minus 2 degree angle of attack.

    I have never seen TheVirus, but I have been telling the same on Russian forum. For most people it is difficult to understand. The best setting angle depends on many things and may be different for the same setup for different people. But in general low liter and narrow board with heavy sailors work better at positive set angle. The set angle is different from the angle of attack.

    But with enough practice you can adjust for the set angle you already have or you can adjust the set angle. Making the set angle adjustable adds cost. It is less cost to try different fly-fins and keep the one that works the best for you.

    Das ist ein sehr guter Artikel. Ich habe es schon einmal gesehen. Die Schlussfolgerung dieses Artikels ist - verbessere das Board (nicht die Flosse). Wir haben das Board verbessert und unser Windsurfer geht schneller mit hoher Geschwindigkeit. Der nächste Schritt ist, es stabiler zu machen. Ich habe einen neuen Prototyp redy für Test. Das erste Bild von Fly_FIN_Konzept Papier muss korrigiert werden. Die Kraft in der FLY_FIN-Richtung ist falsch. Dann muss möglicherweise das gesamte Dokument überarbeitet werden. Es gibt andere Ungenauigkeiten. Sie müssen Dynamik und Aerodynamik hinzufügen, weil moderne Boards schnell sind.


    Please punish me only.

    I am giving you my Russian Soviet honest word that RazeR69 is not working for FRPGear.

    Dr. Zak

    Hi Ray,

    Thank you for coming back to support on this territory.

    Please allow me to address your points one-by-one:

    - If the fly-fin is best for everything – Good point. I even use fly-fin to shovel sand on the beach while watching my kids. Sand works as polishing compound and fin actually gets better. You cannot do the same with most of other fins because the other fins are compression moulded and painted with thin coat of clear epoxy.

    - … it is the first fin in history to be. – For this kind it is "Yes", unless proven otherwise. This is the fist foil one that works and sold in such quantity.

    - Every other fin has to be designed for 1 or 2 advantages: maybe top speed, maybe easy control, etc. – Very much the same applies to Fly-Fins. This why we promote fly-fing for early planing and we promote different design for faster speed at 20 knots wind. We have just discussed these high speed fly-fins above. Many participants noticed that they could balance much better at 30 knots speed compare to the con from frpgear. Agree.

    - Ease of learning will never sell to any windsurfer already sailing. – Perhaps. This is why we promote early planning. And, we have just started to promote higher speed when used in combination with Fly-Boards. It means frpgear is now targeting the board industry with faster boards/fin technology. We have a new board curing as we speak to be ready for test tomorrow.

    - Give a couple to learn windsurf schools and get professional feedback from them. – When we cannot sale fins for money and we have nothing else to do we may be giving out free fins.

    - Maybe the son is just a phenomenal quick learner. – Thank you! His father will appreciate this compliment. You actually the first one who thought about this. All the other comments are very negative towards to the son’s windsurfing skill.

    - Do not use a poor not windsurfer go to sell your idea to a good windsurfer. Use a recognized good windsurfer. – I have been thinking about the same and even gave free sample to one very well recognized. It has been 5 months and the person still not used it. I think you are implying that I need to give a free sample to windsurfers like you to help me in development. I do. The only problem is too much time to wait for the results with extra work for shipping. It takes at least a week to test one design if I give it to you. When I do it with my team we test several designs in one day. We take 5 different fins on a spot and I do modifications right on the spot. This way we could have 25 designs tested in one day.

    - As you are finding, it is very tough to show a real advantage with an honest video. And it is quite possible that there is not a lot of trust in a video. – At some point I agree. But in our experience we have very few people who do not believe in our videos. Only one out of 10 is skeptical about accuracy. 9 out of 10 make negative comments on poor windsurfing skill of our test person. It is like Ford truck advertising. When they show a hard working hansom man driving F150 consumers do not complain on misleading. If they will show a real average F150 driver consumers will probably dislike F150. Look at one French promotional videos of hydrofoil. They always show a half-naked woman with the foil or behind the foil or around. If they show a real average half naked woman nobody would like that French foil. When the sons start dating we may get some bikinis on our videos too.

    - All these people at the Canadian Hole who have seen the fly-fins for themselves ...... Have they immediately bought a fly-fin and taken it back to Canada and write about it on the forums and tell their friends? Are they not that amazed? – These Canadians may be not like you. Why would they drive 3000km to our spot? I think most of them know about us but they are afraid to approach Russians because we use Russian flag sail and USSR symbols painted on our test boards. However, one brave Canadian even asked Dr. Lunin for a picture with him in order to post on his forum. Another Canadian secretly touched our Fly-Board and took many pictures. I told him that it was a secret board – no pictures. And I flipped the board on the other side. But that Canadian came back to take pictures of the secret board from the other side. But, no. We did not have a valid test with others on the spot yet. Another Canadian with two daughters was talking to us because we had two same age hansom boys. Most of people on the spot are just busy with their own problems. But one American tested and liked it but lost the fin because we had a different finbox. I Russian culture it is impolite to ask somebody for a fin to try. Probably need to get used to each other. Canadians have been coming there for decades and we started to go there last October. Many kiters are asking. This is why we sale fly-fins for now for kiteboards.

    - I have had great results with a fly-fin. BUT, I had to attach it to a proper fin to fix many, many problems. What it does for me is 3 things. Very low wind early planing, and / or 2 m. smaller sail, and excellent fin for gusty conditions. (probably because of that 2m less sail; I can start planing early and still handle the huge gusts.) At strong winds I suspect a normal race fin will be faster. And 1 fairly large negative - I have a new way to jibe. It does not do everything better! – You are probably the only one who has successful results with home-made fly-fin. May be frpgear wing/fin integration helped? But your declared results are even harder to believe compare to our results, while we have many videos and you no videos. From another hand, even if you had a video to does not make it easy to believe unless you make a video that looks like a TV commercial. We cannot confirm if it is easy to jibe or not because the son has never used a regular fin to compare. Now, after 10 months of practice, the son can do 1 successful planning jubes out of 10 attempts. It is safe to assume, if continue practicing, the son will be doing planning jubes this season so we will post a video. So we can say that it takes one year for a beginner to learn planning jibes with fly-fin.

    Thank you for participating,


    Danke, dass Sie diese Diskussion zu dem veröffentlichten Dokument geführt haben.

    Gestatten Sie mir, zu den drei Schlussfolgerungen Stellung zu nehmen:


    Es ist normales Gleiten mit geringerem Widerstand bei niedrigen Geschwindigkeiten. - Dr. Zak: "It is also sliding with less resistance at 30 knots speed."

    -Dr. Zak: "Es gleitet mit weniger Widerstand bei 30 Knoten Geschwindigkeit."

    Insbesondere bei höheren Geschwindigkeiten wird es sicher

    nicht einfach, so ein System zu kontrollieren.

    -Dr. Zak: "Im Vergleich zum traditionellen Windsurfen haben wir es leichter zu kontrollieren. In den beiden Videos sehen wir eine Anfängerin mit nur 10 Monaten Training, die fly-fin_concept mit einer Geschwindigkeit von 30 Knoten kontrolliert. Es scheint unmöglich zu sein Blickpunkt eines traditionellen Windsurfer.

    Es fehlt eine Stabilisierungsfläche.

    - Dr. Zak: "Falsch. Es gibt Stibilisationen. Sie sehen es einfach nicht. Ohne Stabilisierung wäre ein Neuling nicht in der Lage, es mit einer Geschwindigkeit von 30 Knoten zu fahren.

    1. Ich zeige Videos als Illustration zum FLY_FIN_KONZEPT.pdf, post # 100 von kleppy10.

    2. Ich erwarte, dass Sie das Gleichgewicht der Kräfte in dem vorgeschlagenen mathematischen Modell von kleppy10 lesen und verstehen. Dies ist ein sehr Anfänger leven von 16 Jahre alten Schüler.

    3. Ich erwarte, dass Sie interessiert sind, warum die Testergebnisse (2 Vidoes) entgegengesetzte Ergebnisse zu kleppy10 Theorie zeigen.

    4. Ich erwarte nicht, dass Sie sich dafür interessieren, warum 10-monatige Erfahrung amerikanischer Windsurfer mit inkorrekter Technik schneller zu einem Kitboarder, erfahrenen Windsurfer und sogar einem Jet Ski gehen kann.

    5. Siehe beigefügten Windbericht. Der Windbericht zeigt 20 Knoten Wind. 20 Knoten Wind bedeutet 30 Knoten Geschwindigkeit des Windsurfer.

    6. Es ist nicht interessant, wenn ein Amerikaner 20 Knoten Wind leicht handhaben kann und nach 10 Monaten Training so schnell wie 30 Knoten geht. Es ist interessant, wenn sogar ein Anfänger Amerikaner die Nase vom Tauchen in Wasser mit 30 Knoten Geschwindigkeit (20 knots wind) halten kann whyle kleppy10 erklärt es als unmöglich in Deutschland.

    7. Im Allgemeinen stimme ich Ihnen zu. Denken Sie darüber nach, was ein erfahrener deutscher Windsurfer mit Fly_Fin_Konzept tun kann, wenn selbst ein Amerikaner mit nur 10 Monaten Training es so schwer macht zu glauben.

    Bitte erlauben Sie mir, praktische Fragen zu stellen:

    Frage 1.

    Denkst du, du könntest das Fly_Fin_Konzept besser kontrollieren? Würdest du schneller gehen?

    Frage 2.

    Auf dem Video, wo Fly_Fin_Konzept viel schneller geht, verglichen mit einem erfahrenen kanadischen Windsurfer? Was denken Sie, dass Kanadier lockerer waren, könnte es besser machen, um schneller zu werden. Ich kann auf dem Video sehen, dass der erfahrene Kanadier versuchte, gegen den Wind zu beschleunigen, aber immer noch an Fly_Fin_Konzept verloren hatte?

    Vielen Dank.


    • Wind speed.png

      (154,11 kB, 9 Mal heruntergeladen, zuletzt: )

    und was sollen die Videos zeigen ?

    Zwei mittelmäßige Surfer mit schlechter Kontrolle, und ein Kiter

    Entschuldigung für mein Deutsch. Sie müssen FLY_FIN_KONZEPT.pdf, Post # 100 von kleppy10 verstehen, um meinen Post mit den Videos zu verstehen. Bitte ignorieren Sie einfach die Videos, wenn Sie das vorgeschlagene Gleichgewicht von FLY_FIN_KONZEPT.pdf nicht verstehen.

    Ich erwarte, dass kleppy10 auf den Videos kommen wird. kleypy10 hat FLY_FIN_KONZEPT.pdf gepostet, um zu erklären, warum Fly-Fin die Rückseite des Surfbretts hebt. Die Videos zeigen gegenüber - Fly-Fin hebt das Geräusch des Surfbretts. Ich habe die beiden Videos gepostet, um zu sagen, dass FLY_FIN_KONZEPT.pdf für FLY_FIN_KONZEPT nicht vollständig korrekt ist.

    Aber danke, dass du die Videos angeschaut und nicht relevante Details kommentiert hast. Du hast Recht. Der Windsurfer, der schneller geht (Greem Segel) hat FLY_FIN_KONZEPT. Auf dem ersten Video ist FLY_FIN_KONZEPT schneller zu vergleichen mit einem traditionellen Windsurfer. Das andere Video FLY_FIN_KONZEPT ist schneller mit einem Kiteboard vergleichbar. Ich stimme zu, dass der Windsurfer mehr Kontrolle braucht. Die Person auf FLY_FIN_KONZEPT hat vor 10 Monaten mit dem Windsurfen begonnen. Man kann daraus schließen, dass eine erfahrenere Person noch mehr Kontrolle haben wird und noch schneller gehen wird. Ich verstehe, dass es sich bei FLY_FIN_KONZEPT.pdf von kleppy10 um einen erfahrenen Windsurfer handelt. Ein Video zeigt zwei Windsurfer. Langsamer, aber erfahrener Windsurfer mit guter Kontrolle ohne FLY_FIN_KONZEPT.pdf. Schneller unerfahrener Windsurfer mit FLY_FIN_KONZEPT.pdf aber außer Kontrolle geraten. Vielleicht, Ihr Hinweis auf schlechte Kontrolle, dass FLY_FIN_KONZEPT zu schnell ist, vergleichen Sie mit erfahrenen Windsurfer und Kiteboarder. Ich habe die Videos in den USA gemacht. Die USA-Regierung kontrolliert nicht die Geschwindigkeit der Widsurfers in diesem Wasserpark. Es ist in Ordnung, an diesem Ort so schnell zu sein, wie Sie möchten und außer Kontrolle geraten. Aber vielleicht habe ich nicht verstanden, was du meinst. Meinst du, dass FLY_FIN_KONZEPT es schwierig macht zu kontrollieren? Ich bin nicht einverstanden. Ich denke, die Person mit FLY_FIN_KONZEPT steuert nach nur 10 Monaten Übung 30 Knoten Geschwindigkeit. FLY_FIN_KONZEPT heps zur Steuerung. Ich habe ein anderes Video ohne FLY_FIN_KONZEPT, um schlechte Kontrolle zu zeigen. Sieh dir den Kopf des Kiteboarders an. Er betrachtet den Windsurfer mit FLY_FIN_KONZEPT und denkt: "Ich habe so viel Kontrolle. Warum bin ich so langsam?":)

    Einige Anmerkungen zum Fly-Fins-Konzept


    Dieses mathematische Modell berücksichtigt einige kritische Details nicht. Ich mag ein Fehler sein, aber dieses Modell erklärt nicht, warum man mit hoher Geschwindigkeit fahren kann und die Vorderseite des Boards hoch über Wasser hält. Sehen Sie sich die letzten Youtube-Videos an. Aber dieses Modell erklärt, warum Sie sich mit hoher Geschwindigkeit etwas zurück bewegen müssen. Aus meiner persönlichen Erfahrung kann ich Ihnen sagen, dass Sie persönlich am Test teilnehmen müssen, um ein korrektes mathematisches Modell des Systems zu erstellen. Das vorgeschlagene mathematische Modell sagt mir, dass Fly-Fin nicht funktioniert, weil die Nase ins Wasser gehen wird. Das Experiment sagt mir, dass die Nase nicht ins Wasser geht. Meine Frage ist: Ist es möglich, das vorgeschlagene mathematische Modell zu korrigieren, um das Windsurfen von Fli-Fin genau zu beschreiben?

    Es gibt ein Problem. Man kann einfach bei kaufen. Aber man kann nicht einfach von Thevirus kaufen. Es ist unmöglich, einen Vergleich zu machen.

    Man kann unangemessene vergleichen. Sehen Sie sich die Website von frpgear theVirus Website an. Man kann viele Modelle auf einer Website und nur eine auf theVirus-Website sehen.

    Es ist sicher davon auszugehen, dass der Umsatz von Frpgear höher ist. Wenn Sie mehr verkaufen, bedeutet es, dass die Leute es mehr mögen. Ich bin in den USA. Ich habe theVirus in den USA nicht gesehen.

    Kennst du jemanden, der theVirus in deiner Gegend benutzt? Siehst du irgendwelche Videos theVirus? Auch, warum sollte frpgear gegen theVirus vergleichen wollen, wenn niemand will, kauft theVirus?


    Lamgsam wird es hier echt unerträglich....


    Besser als nichts. Ray machte diese Diskussion aktiv. Du und ich haben es unterstützt. Jetzt reden wir. Wind ist heute nicht gut an meiner Stelle. Nichts zu tun.

    Wie geht es Wolfgand mit seinem Projekt?

    Whatever. I have long since learned that with FRP the customer is always wrong.


    You and Cesar have invited word public to discuss frpgear fly-fins on your FaceBook pages. In the same time, you and Cesar blocked frpgear from posting on on your FaceBook pages.

    And, we, at frpgear, like to think about our customers more like about out partners helping us to make the sport of windsurfing better.

    Dr. Zak.

    Dr. Zak, you and Dr. Lunin manufacture and sell fly-fins.

    But more importantly:

    We: Dr. Zak and Dr. Lunin have invented Fly-Fin and made it work.

    As you may have already researched there have been repeated attempts for 40 years to make a usable Fly-Fin. FRPGear has finally got it right. Only RazeR69 is complaining, but still using our Fly-Fin invention. Our Fly-Fin is probably so good - even when someone picks a wrong size like Raze69 did you can still make it work without being an educated Ph.D.

    Here are more facts:

    RazeR69 payed with Paypal:

    Hydrofoil fin S-Glass Fin, Tuttle Box. 1/4-20 $290.00 USD + Shipping $24.50 USD

    FRPGEAR paid: PayPal Fee-$14.14 USD

    FRPGear ended up with 290-14.14=$275.6US. Subtract taxes, materials and labor cost. It means Dr. Lunin and I do not do this for money.

    We ship it with declared value of $200 for shipping cost reduction or with no declared value when customers with high import tax ask. So it should not be high custom cost on import.

    Yes, you will need to pay your own shipping cost of $24.50 if you want to ship it back for a complete refund. From your recent post I see that paying for the return shipping was an important issue for you. From your other posts I see that you have decided to keep this low cost model in order to get 50% discount for a significantly more expensive model that would be a correct fly-fin for your board. In other words, instead of buying $900 fly-fin you purchased $290 fly-fin in order to become eligible for 50% discount on $900 fly-fin. In result, you would pay as low as $290+$450= $740 total for two: $290 + $900 fly-fins instead of paying $900 for only one fly-fin. Dr. Lunin has already discussed these options with you after you have been trying to cancel you $290 order with PayPal when you found the same but lower price Fly-Fin available on eBay for $288. eBay does not provide benefits on the second purchase.

    We do not compare Fly-Fin cost to a regular fin cost. We compare Fly-Fin cost for light wind planing to the cost of other options for light wind planing. For example, I have purchased a used 100L AHD and new NP racing sail 5m for $450 total. With frpgear 2018-Winglets I (80kg) get on planing at 9 knotes compare to 13 knots wind with a regular fin. How much money do you think I need to get on planing at 9 knots wind without fly-fin?

    When you refer to your own fly-fin I am getting confused because you are showing pictures of frpgear fly-fin. Yes, you added more fin area and adjusted setting angles. But it remains frpgear fly-fin. As they like to say today: "If it looks like, works like, used like, made like, promoted as, purchased from, made out of frpgear fly-fin it is frpgear fly-fin."

    Nicht war?

    Dr. Lunin

    P.S. Sollen wir hier deutsch sprechen?

    Hi RazeR69,

    In educated world Doctors provide references when making claims. For example, when I did my Doctor's dissertation in math modeling I had to get publications in magazines where my publications are approved by several independent scientists. Presentations on scientific conferences and Patents work too. For example one of my earlier Euro Patents SU19884616281 19881109 can be found and checked. The underlying idea of an evidence is to prevent self proclaimed (fake) but ambitious scientists to gain power. When we, experienced and educated engineers, make a claim we intend to support it with evidence in order to make it possible for others to replicate our results. For example, frpgear provides videos, wind conditions, sailor weight and experience, details about equipment used. You can either agree on frpgear results or replicate the same conditions in order to verify. You cannot oppose an engineering test result by just talking about it based on your own thoughts. The actual experiment has priority over theories. Your claim that frpger fly-fin "sucks and useless" remains an allegation to be proven. The same with your claim that you get on planing at 3 m/s wind speed under 6 m^2 sail. My point here is that somebody needs to be able to verify your claim to make it a fact. The best way to get somebody to verify what you discovered is to post some videos of you doing actual windsurfing and show differences between frpgear and other fins. Like you can see on frpgear youtube videos side by side. Because the videos are not enough you should give your fins to others to try and compare. For example, we have delivered many fly-fins and we have some negative comments as we can see. But these negative comments are more emotional and without actual video evidence to support. Is it still a problem today to take a phone video? I would love to see your videos from Cuba. For example you have 50 posts on several forums about your experience + 30 emails to frpgear. It seems you put much effort to talk about it and apparently no effort to show any video of the problem. Frankly, I was unable to find any picture or a video of you doing any windsurfing considering you claim to be the one with the experience. The same question I have to your partners like Cesar Ramon. Cesar Ramon has a Facebook page that has been just created for criticizing frpgear 2019 model, again without any videos of the problem. The only picture I see from Cesar Ramon is frpgear model 2019 packed for shipping and I can see it has been shipped immediately after he received it. He spent more time for critics of frpgear model 2019 compare to time of trying it on water. And, no any pictures or videos of model 2019 with Cesar Ramon on water or on a beach or anywhere with 2019 model and Cesar Ramon together. And, why do you think I shipped Model 2018 to Taiwan, while payment from Cesar Ramon came from Spain? Why do you think Cesar Ramon picked the wrong model for his board (just like you) while I suggested to get a correct model? The devil is in the details as they say. And, who is Deska from Hatteras? I actually live and windsurf in the area for 20 years and I have never met a windsurfer Deska from Hatteras. Is he the one from this Drama video:

    We, at frpgear, have now 5 different boards. When we get new test results we publish videos. You can find two the most recent videos of -700 and April models on Formula like board and 2019 Model on our new design Fly-Board. Real videos of real windsurfers on the equipment that we can describe in fine details so you can verify the results. BTW, you could just have bought our -700 model for 50% discount instead of making your own. But, our April model works better on Formula compare to -700. If you asked me when bought a lower cost and outdated model I would suggest get April 2018 for your board instead. I actually have 2018 April test model available with Tuttle box and M6 for 50% discount and free shipping.

    There is always a better way to windsurf.

    Mit freundlichen Grüßen

    Dr. Zak.

    Hi RazeR69,

    I admire your humor. I am originally from USSR and I used to work with engineers from DDR and BDR. What I liked the most about German engineering culture is the respect to education. It is considered to be polite in Germany to address a person by a title. For example, if you have an equivalent of American Ph.D. you will be most likely addressed by "Dr" in Germany. I have seen similar custom in China and Iran. I agree with you that most of the North American population would make a joke about signing your letter with "Dr." This is one of the reasons I like this German forum. The other reason to like this German forum is because it has higher level of understanding of the engineering specifics in comparison to, for example, boards UK forum. You can see it by compare the fly-fin that Wolfgang built on this forum to all the fly-fin prototypes published on the UK forum.

    I have noticed your 40+ recent comments on the UK forum. I have also viewed your 30+ emails to frpgear. My understanding is that you are asking frpgear to build fly-fins for you and for your friends per your specification for free in exchange for you publishing good reviews. In order to convince frpgear to accept your offer you criticize frpgear design.

    You are not alone in the effort to get free fly-fins. We are receiving such of offers often enough. Most of our prospective partners understand our current situation - we are focusing more on engineering and less on monetizing. But some people get angry on us for declining free product shipment. You can find those partners on forum, like FightingFools on the UK and other forums who never used fly-fins. They typically say that we have to give fly-fins to an experienced sailor referring to themselves, despite we have already given a number of fins for free to other experienced sailors.

    In your particular situation my suggestion is to get a correct fly-fin for your board. We have been advertising 2017 (currently discontinued) model for older long and narrow boards. Your board is too wide for our old 2017 fly-fin. Our-700 model is more like the one you made out of our 2017. But our April 2018 model performs much better on wide boards compare to -700 model:

    To comment on your question for a custom fly-fin: Yes, we make custom fly-fins.

    To comment on your concern about believing in your test results: Yes, we are having a similar problem. Despite over 30 videos posted on YouTube many forum posters remain skeptical.


    Dr. Zak

    Lieber Dr. Spin Out,

    Danke für die Nachfrage. Ich habe nur 5 Patente. Wir bieten Structural Glass, Carbon, Kevlar. Unser Platzierungsprozess ist wahrscheinlich anders als Ihr Prozess. Wir haben uns nie beschwert, dass Fliegenflossen versagen. Seit Oktober 2017 haben wir nur 2 Kunden, die sich öffentlich über die Leistung im Internet beschweren. Wir haben insgesamt 3 Retouren für 100% das geld zuruk gekomen wegen falscher Auswahl. Ich denke, das ist ein gutes Ergebnis. Wir verkaufen ungefähr 60% des Produktes aus Carbon.


    Dr. Zak.