Basic gear from mid-twentieth-century Italy: Mares and Pirelli

[David Wilson]

Let's fast-forward to the Sea King fin page of the Mares catalogue of 1969:

Italian: "Articolo 1000. Pinna Sea King non galleggiante. Articolo 100f. Pinna Sea King galleggiante. Sea King la pinna perfetta, morbida, leggera. Scarpetta con suola ortopedica ad apertura anteriore. Costone centrale brevettato. Pala e coste laterali in gomma rigida. La calzata in gomma molto morbida non indolenzisce il piede. L'accentuata inclinazione fornisce la massima potenza nel nuoto. Viene prodotta nel tipo normale e galleggiante. Misure: 24/26 - 27/29 - 30/32 - 33/34 - 35/36 - 37/38 - 39/40 - 41/42 - 43/44 - 45/46."
English: "Item 1000. Non-floating Sea King Fins. Item 1001. Floating Sea King Fins. Sea King, the perfect fin, soft and light. Full open-toe foot pocket with support under the ball of the foot. Patented midrib. Blade and side rails of stiff rubber. The foot pocket of very soft pliable rubber eliminates foot-cramp. The tapered ribs provide maximum power. Available in two types: floating and non-floating. Sizes: 24/26 - 27/29 - 30/32 - 33/34 - 35/36 - 37/38 - 39/40 - 41/42 - 43/44 - 45/46."
French: "Article 1000. Sea King non-flottantes. Article 1001. Sea King flottantes. Sea-King la plus parfaite, la plus souple, la plus légère, la plus efficiente des palmes. Modèle chaussant avec semelle orthopédique et ouverture antérieure. Côtes brevetées. Le soulier en caoutchouc souple ne fatigue pas le pied. Le galbe bien étudié, assure à la nage un meilleur rendement. Caoutchouc flottant ou non flottant. Pointures: 24/26 - 27/29 - 30/32 - 33/34 - 35/36 - 37/38 - 39/40 - 41/42 - 43/44 - 45/46."

I haven't yet been able to identify the midrib patent mentioned in the product description. Compare the breadth of the toe opening on the Caraibi and the Sea King and note how the latter is less likely to tear at the sides than the former.

1974

1975

1976

Italian: "Leggera ed efficiente. Una calzata confortevole aperta sul davanti. Angolazione studiata, nervatura brevettata. È per eccellenza la prima pinna, senza problemi, ad alto rendimento."
English: "Light and efficient. Soft wearing. Open on the front. Specially studied inclination, patented ribbing. The first problem-free high-performance fin."
German: "Leicht und wirksam. Gute Passform und offener Frontteil. Eine durchdachte Form. Mit patentierten Profilen. Eigenschaft: eine problemlose Flosse mit hoher Lebensdauer."
French: "Légères et efficaces. Chaussant confortable ouvert devant. Angle spécialement étudié, nervures brevetées. Elles sont par excellence les premières palmes à rendement élevé sans problèmes."
Spanish: "Livianas y eficientes. Calzado confortable. Abiertas hacia el exterior. Perfil cuidadosamente estudiado, nervaduras patentadas. Son las aletas por excelencia, sin problemas y de alto rendimiento."

 

[David Wilson]

We'll conclude today with a few photographs of Mares Sea Kings:

To complete the story of the Mares Sea King fin, we have to cross the Bosphorus to Istanbul, where these fin moulds right below were later sent:

Behold the reincarnation of the Italian Mares Sea King as the Turkish Adililar Kauçuk Süper Star:

If you can figure out the mechanics and the linguistics of a Turkish online retail site, you might be able to purchase a pair, or you may be able to seek out a pair if you ever travel to a Turkish beach resort. I have a pair in my fin collection and they're every bit as comfortable the Italian originals.

And there I'll leave things until the weekend comes around. Then I'll review the Mares "OK" fin with vented blades. Stay safe, keep well and let's hope the promised vaccine turns out to be the game-changer when it is eventually offered to the general public.

 

[lowwall]

Behold the reincarnation of the Italian Mares Sea King as the Turkish Adililar Kauçuk Süper Star:
View attachment 623407
If you can figure out the mechanics and the linguistics of a Turkish online retail site, you might be able to purchase a pair, or you may be able to seek out a pair if you ever travel to a Turkish beach resort. I have a pair in my fin collection and they're every bit as comfortable the Italian originals.

A small correction. It's Adalılar, not Adiliar. And it appears the current model name is Süper Jet.

Here's the current lineup from one seller. But first a few necessary translations.

Kaučuk - rubber
Palet - fin
Kisa - short
Batmaz - buoyant

https://www.hepsiburada.com/adalilar?sayfa=1#

 

[David Wilson]

A small correction. It's Adalılar, not Adiliar. And it appears the current model name is Süper Jet.

Here's the current lineup from one seller. But first a few necessary translations.

Kaučuk - rubber
Palet - fin
Kisa - short
Batmaz - buoyant

https://www.hepsiburada.com/adalilar?sayfa=1#

Thank you so much, Iowwall. As a modern linguist, I should have proofread that portion of my posting much more thoroughly. That's what comes from rushing things when today's contribution took me a little longer than usual to compile. How come you know Turkish so well?

 

[lowwall]

How come you know Turkish so well?

Google translate, like everyone else

Although both kaučuk and palet appeared to be obvious loan words from caoutchouc and palette, I've gotten into trouble assuming that meanings accompany their spellings over a border, so I verified with Google translate. While I had it open, I checked the other two.

BTW, I've looked up these fins before as I would like a shorter alternative to my full foot Mares Superchannels for tropical dive vacations. I had a Turkish friend look over the shopping sites with me, but we concluded it didn't make sense to try to get them shipped to the US.

 

[David Wilson]

Thanks again, Iowwall, and I value your advice about Turkish online retailers!

Just a little niggle: I believe "kaučuk" with its C with caron (Č) is the Slovak version of "caoutchouc", which is in turn French for "rubber", while "kauçuk" with its C with cedilla (Ç) is the Turkish counterpart for that "Tch" (/t͡ʃ/) sound. "Palet" is indeed the singular Turkish noun for "swimfin" as well as "palette" and its plural is "paletler". "Batmaz palet" apears to be Turkish for "floating fin", echoing your rendering of "batmaz" as "buoyant". You were right to correct me when I wrote "Adililar" instead of "Adalılar", which contains the dotless lowercase "ı". Turkish has two versions of the Roman character "I", one dotless both upper and lower case, "I ı", the other dotted both upper and lower case "İ i"; pronunciation difference explained at Dotted and dotless I - Wikipedia. By the way "Adalılar kauçuk", the name of the Istanbul fin manufacturer, apparently means "Islanders rubber" in Turkish. Turkish seems a fascinating language, unrelated to European languages, but containing plenty of loanwords from them such as "kauçuk" and "palet".

 

[David Wilson]

Thanks to everybody for the likes and feedback! And now on to the Mares OK fin. I'm not intending to explain the origin of the product name "OK", because the American English derivation spelled "OK" or "Okay" seems obvious. I will venture to say, though, that the etymology of the American English term meaning "all right" is itself disputed, but I'll offer what is Google's explanation: "OK: probably an abbreviation of orl korrect, humorous form of all correct, popularized as a slogan during President Van Buren's re-election campaign of 1840 in the US; his nickname Old Kinderhook (derived from his birthplace) provided the initials." Amazing how so much many things revolve around American presidential ellections, past and present...

The years of birth and introduction of the Mares OK fin appear to be 1966 and 1967 respectively:

Italian: "OK. LA PRIMA GRANDE NOVITÀ MARES PER IL 1967 LA PINNA MULTIPLA «difatti le 2 pale mobili, ricavate dall’intera pala, consentono il passaggio dell'acqua nella zona morta. Le 2 pale determinano delle superfici inclinate con effetto di propulsione concorde a quello della pala principale. La pinna può così considerarsi composta da una pinna principale e da due pinne ausiliarie che si flettono tutte e tre singolarmente ed elasticamente nello stesso senso durante il moto e concorrono per determinare la spinta di propulsione totale che risulta notevolmente maggiore di quello ottieni con le pinne tradizionali». La pinna inizia la sua corsa verso il basso, le pale mobili vengono sospinte verso l'alto dalla pressione dell'acqua; si ottiene così: l'apertura di scarico della zona morta. Nel secondo movimento la pinna procede verso l'alto e le pale ricevono una spinta verso il basso lasciando, anche questa volta l'apertura di scarico."
Rough translation: "OK. THE FIRST MAJOR INNOVATION FROM MARES FOR 1967. THE MULTIPLE FIN 'as a matter of fact, the 2 movable blades, obtained from the entire blade, allow the passage of water in the dead zone. The 2 blades establish inclined surfaces with a propulsion effect concordant with that of the main blade. The fin can therefore be considered to have the composition of a main fin and two auxiliary fins with all three flexing individually and elastically in the same direction during motion and contributing to the establishment of the total propulsion thrust which is considerably greater than the one obtained with traditional fins.' The fin begins its downward stroke, the moving blades are pushed upwards by the water pressure, the result being: the dead zone discharge opens. In the second movement the fin proceeds upwards and the blades receive a thrust downwards, once again tthe discharge opens."

Leaving the hydronamics to the physicists, I'll simply say that the "OK" fin appears to be Mares' response to the Beuchat "Jetfin" and the Cressi "Super Rondine" fins:

1967

The French Plongées magazine ad above demonstrates how the Mares OK fin was exported to other countries. The French caption lauds the OK as "révolutionnaire" (revolutionary) and "la palme à réaction", which translates into English as "the jet fin", which must have proved a little galling to Georges Beuchat of Marseilles, the original French manufacturer of "la palme à tuyères", which translates into English as "the jet fin" too! As it turned out, of course, neither Beuchat nor Scubapro need have worried as the Mares OK fin has not survived while the Jetfin/Jet Fin is still with us today.

 

[David Wilson]

Let's fast forward once again to 1969:

Italian: "Articolo 1002. Pinna Multipla O.K. non galleggiante Articolo 1003. Pinna Multipla O.K. galleggiante. E' una pinna speciale che sfrutta determinati principi fisici della propulsione, avvicinandosi nell'effetto alla spinta che si ha coi propulsori a reazione. Nelle pinne normali la parte anteriore flessibile della pala viene a costituire un piano inclinato rispetto alla resistenza dell'acqua, che determina la spinta in avanti. La pinna O.K. presenta invece, nella parte inerte della pala due alettoni mobili nei due sensi. Con questo accorgimento è stato eliminato l'attrito nella falcata positiva, quella dal basso verso l'alto, che non apportava alcun contributo alla spinta, mentre riusciva decisamente dannoso nella falcata negativa, dall'alto verso il basso, costringendo il subacqueo ad uno sforzo inutile. In entrambi i movimenti, i due alettoni si flettono di alcuni gradi sotto la pressione dell'acqua la quale, attraversando le feritoie rimaste aperte esce dalla parte opposta provocando, per reazione, una spinta di avanzamento. Inoltre, scorrendo lungo la superficie opposta a quella di spinta sia nell’'una che nell'altra falcata, l'acqua elimina il risucchio consentendo in tal modo un notevolissimo risparmio di energia. Gli alettoni, inoltre, funzionano a loro volta come pinnette ausiliarie, rendendo attiva la parte inerte della pala. Orientate nello stesso senso della pinna principale, queste pinnette ausiliarie vengono a determinare piani inclinati che uniformano la loro azione di spinta a quella della pala principale. Da qui la denominazione di pinna natatoria Multipla. La O.K. si differenzia inoltre dalle pinne tradizionali per le costole irrobustite e arrotondate, per la suola della scarpetta in gomma rigida per quasi tutta la lunghezza, per le fasce di irrobustimento all'entrata e all'uscita della calzata. La pinna multipla O.K. viene fabbricata in gomma nera non galleggiante, con una mescola, risultata dopo lunghe esperienze la più elastica e scattante tra quelle a tutt'oggi reperibili sul mercato. Misure: 37/38 - 39/40 - 41/42 - 43/44 - 45/46 - 47/48."
English: "Item 1002. Non-floating O.K. fins. Item 1003. Floating O.K. fins. These are a special type of fin, which exploit physical principles of propulsion, approaching the effect of the impulse which exists with jet propellers. With the ordinary type of fin the flexible frontpiece of the blade forms a tapered downward curving plane to reduce water drag, resulting in forward thrust. The O.K. fins instead present in the negative blade area two flaps, movable in both directions. With this inclination the discord has been eliminated in the positive, Le. the upward thrust, which did not contribute at all to the stroke and succeeded instead to decrease decisively the downward thrust, forcing the diver to needless effort. In all the movements the two flaps bend for a few degrees under the pressure of the water, which — channelled through the vents that remained open — flows away from the opposite part, creating continuous propulsion and eliminating water drag, allowing thus a remarkable saving o energy. The flaps act moreover in their turn as auxiliary fins, transforming the negative blade area into a positive one. Orientated in the same direction as the principal fins, these auxiliary fins are curved blades, which combine their thrust with that of the principal ones, giving first class performance. Hence the name Multiple. The O.K. fins differ furthermore from the traditional fins by their strong and tapered ribs, the rigid sole of the rubber foot over about the whole length. The O.K. fin is produced in black non-floating rubber and of a compound, the result of a long experience, which is the most elastic and resilient amongst those at present available on the market."
French: "Article 1002. Palme O.K. Multiple non-flottantes. Article 1003. Palme O.K. Multiple flottantes. C'est une palme spéciale qui utilise des principes physiques très précis comparables au principe de la propulsion à réaction. Dans les modèles de palmes traditionnels, la partie antérieure souple de la palme, qui constitue la partie propulsive, oppose un plan incliné à la résistance de l'eau. La palme O.K. par contre, présente sur la surface négative, deux ailerons mobiles dans les deux sens. Ainsi se trouve éliminée une partie de la résistance de l'eau, néfaste à la propulsion, dans la phase positive du battement (de bas en haut) cependant que la phase négative (de haut en bas) nécessite moins d'efforts inutiles de la part du nageur. Dans les deux phases du battement, les deux ailerons fléchissent de quelques degrés sous la pression de l'eau qui passe au travers des ouïes, créant par réaction une poussée propulsive. De plus, l'eau glissant sur le plan opposé au plan de propulsion, élimine dans les deux mouvements les remous, et permet une épargne considérable de force. Ainsi, les deux ailerons qui fonctionnent comme deux palmes auxiliaires, activent la partie négative de la palme. Ils forment avec la palme proprement dite et dans la même axe, que celle-ci. des plans propulsifs qui accroissent sa puissance, d'où son surnom de palme multiple. La palme OK. diffère encore des autres modèles standard, par sa conception plus robuste et aérodynamique, par sa semelle rigide sur toute sa longueur, par ses arêtes externes renforcées. La palme O.K. est produite en caoutchouc noir, non flottant, avec un mélange de gomme, très éprouvé, et ayant donné les résultats les plus probants d'élasticité. Pointures: 37/38 - 39/40 - 41/42 - 43/44 - 45/46 - 47/48."

I'll let the product descriptions do the explaining and focus a little on the translations. The mechanics of these fins are described in aeronautical terms, the English having "flaps" and the French "ailerons" to denote the strips cut out of the blades to improve thrust efficiency. This imagery likens the OK fin blade to an aircraft's wing more than its engine.

1974

1974 may have been the last year when "OK" fins graced a Mares catalogue.

 

[David Wilson]

We have already seen how Mares OKs were a little cheekily exported to France, where Beuchat dominated diving equipment manufacturing. The fins also showed up States-side during the early 1970s as "Mares OK Hydro-Vent Fins: Choice of Champions" in the Elton line of diving equipment advertised above in Skin Diver Magazine. Here are some pictures of actual Mares OK fins:

​

And that's plenty for today. Our next port of call midweek will be the Mares Concorde. Still under national lockdown here in the UK, indeed so until early December, so I again express the hope that everybody will remain safe and well until we meet again online.

 

[Angelo Farina]

I remember, at the time, that we made several experiments with the three types of fins: Beuchat Jetfine, Cressi Super Rondine and Mares OK.
The three fins are only apparently similar, in reality they wok on three different approaches: The Jetfin canalizes the water flow in channels angled in such a way to provide a significant thrust in the proper direction during the forward kick (the movement traditionally less efficient with flat fins aligned with the feet). However, such channels are ineffective during the backward kick.
The Super Rondine has an opening vane, which releases the water through the fin reducing the kicking effort, but not providing any significant increment in the thrust. This vane closes during the backward kick, which was instead more efficient, as now the fin is a single large flat fin, with no channels, and properly angled for providing thrust aligned with the direction of motion.
The Mares OK was an attempt to override both limitations, as the vanes are much more rigid than in the Cressi, so they keep a reasonable angle during their opening, providing thrust in the proper direction. They open during both forward and rear kicks, and in theory they improve the thrust reducing the effort during both actions. The idea was clever, but the practical realisation was not: the fins where too short and the vanes too soft, so in practice the thrust was very limited, and needed to be obtained increasing the kick rate. These fins were great for short bursts, but not suitable for long, sustained swimming.
In the end it was discovered that, employing proper kicking style (which indeed must be learned following proper finned-swimming courses), the use of long, flexible blades with no channels and no vanes was far much better. So the Mares Concorde Scarpati and the Cressi Rondine L appeared, outperforming all these attempts with complex geometries. Quite soon rubber was replaced by high-elasticity plastic composites, often reinforced with fibers, evolving in the Rondine Gara and other similar fins, which are still used today by free divers for their optimal efficiency.
The Jetfin, instead, evolved backward in the shorter and more rigid Scubapro version, which is not so efficient as the Beuchat version, but is highly controllable, so it became the reference for cave and wreck diving, where long, flexible fins are very dangerous for the risk of raising silt.