======== Newsgroups: alt.surfing Subject: Longboard vs. Shortboard From: "Madison" Date: 11 Apr 1997 00:40:59 GMT I am a surfer in Myrtle Beach, SC and have a 6' 6" Perfection board. The waves around here are pretty small (4 ft. is decent) and my board doesn't ride them that well. I was wondering if I would be better off with a longboard, and if so, what length and type? Does a longboard ride small waves better? What are the pros and cons? If anyone knows anything about this, e-mail me at teacher@sccoast.net or post the reply on this newsgroup. ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: gleshna@aol.com (Gleshna) Date: 13 Apr 1997 23:58:32 GMT I always ride what is now called a longboard. The biggest waves I have access to are should high at most. The guys on a short board seem to have a much harder time in small or unsteep waves. The turn is slower and will take some getting used to doing. On the positive side you get more glide and a chance to do nose rides, etc. Luck, Bob ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: hangten Date: 15 Apr 1997 07:19:19 GMT Two of the best comparisons of Longboard vs. Shortboard: Bruce Brown (!): Shortboarding is like breakdancing. Longboarding is like ballet. or as a letter to SURFER put it: Shortboarding is like having sex with the wave, longboarding is like making love to it. ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: surffohio@aol.com (SurffOhio) Date: 16 Apr 1997 03:03:33 GMT hangten someone whom I have never seen on alt.surfing but hope to see more, writes: >Bruce Brown (!): Shortboarding is like breakdancing. Longboarding is >like ballet. >or as a letter to SURFER put it: Shortboarding is like having sex with >the wave, longboarding is like making love to it. I love it. Smacks of higher reason. Foondoggy, you once had a thread "Shortboard personality vs longboard personality". It was brilliant. Don't let the doughnut jokes get you down. Come up with more stuff like that. Surff ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: surffohio@aol.com (SurffOhio) Date: 15 Apr 1997 16:00:07 GMT "Madison" writes: >I am a surfer in Myrtle Beach, SC and have a 6' 6" Perfection board. The >waves around here are pretty small (4 ft. is decent) and my board doesn't >ride them that well. I was wondering if I would be better off with a >longboard, and if so, what length and type? If you want to surf on the east coast a 9' longboard is almost a must. Sure, you can wait around for big enough surf for a shortboard, but I guess you'd have to play a lot of golf or something. As to type, find someone that shapes a lot for east coast surf. A good east coast shaper will dialed in to what you need in terms of your body weight, etc. In my experience, a custom board won't cost more than one off the rack. There's a good shaper in Kitty Hawk. His name is Micheal Price. You can get his number from information. Good luck, Surff ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: chunder@wam.umd.edu (Goofus and Gallant) Date: 16 Apr 1997 14:23:32 GMT SurffOhio (surffohio@aol.com) wrote: : "Madison" writes: : There's a good shaper in Kitty Hawk. His name is Micheal Price. You can : get his number from information. I would have to wholeheartedly agree with this. In 1992 I did the switch from short to longboards. My first longboard was a Michael Price 9ft Surfblades. Was an exceptional longbaord, very loose, got into waves great, etc etc. He is really wired into shaping longboards. He's worth looking up. Ben -- If your stick aint long, dont put it where it's wet -First Street Longboard Association ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: gadgetpjt@aol.com Date: 17 Apr 1997 15:01:39 GMT Where are all the shortboarders? Come on kids, hold your end up. Or haven't you got back from your Easter vacation yet? Hello my name is Gadget, and I am a longboarder... [phew, I feel better for that] -------------------------------------------------------------------------- Gadget [Bude, Cornwall, UK] email: gadgetpjt@aol.com A longboarder who has seen the error of his ways, but is subject to the odd lapse... resist the dark side... the force is strong Luke. -------------------------------------------------------------------------- ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: 102476.2613@compuserve.com Date: Tue, 15 Apr 1997 16:41:03 -0600 In article <01bc4611$0c301f80$97bf74cc@default>, "Madison" wrote: > What are the pros and cons? I compare the two this way: Shortboard: Like driving a 930 Turbo. Longboard: Like driving a Lincon Towncar. Both are fun and can get you where ya wanna go in style Surf4life -------------------==== Posted via Deja News ====----------------------- http://www.dejanews.com/ Search, Read, Post to Usenet ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: gadgetpjt@aol.com (Gadget PJT) Date: 17 Apr 1997 22:16:11 GMT Surf4life, 102476.2613@compuserve.com writes: >I compare the two this way: > >Shortboard: Like driving a 930 Turbo. >Longboard: Like driving a Lincon Towncar. Nah, Shortboard: Like riding a moped Longboard: Like Driving a 40 tonne truck One's fun when the weather's right, the others good for intimidation. -------------------------------------------------------------------------- Gadget [Bude, Cornwall, UK] email: gadgetpjt@aol.com Fat girls and Mopeds - they're both fun to ride, but you wouldn't tell your friends about it. -------------------------------------------------------------------------- ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: CyberEyes Date: Wed, 16 Apr 1997 00:05:24 -0700 Madison wrote: > > I am a surfer in Myrtle Beach, SC and have a 6' 6" Perfection board. The > waves around here are pretty small (4 ft. is decent) and my board doesn't > ride them that well. I was wondering if I would be better off with a > longboard, and if so, what length and type? Does a longboard ride small > waves better? What are the pros and cons? If anyone knows anything about > this, e-mail me at teacher@sccoast.net or post the reply on this newsgroup. Hiyaz! Well, I'm not an experienced surfer, but from what I know, surfing on a longboard on small waves is much better than using a shortboard on small waves. I used a 9 foot longboard in Santa Cruz during the summer of about a 2-3 foot wave and I managed to get up. I was stoked. My 2nd time surfing in two years. :) So, there's your answer. Regards, Ryan -- Ryan A. Rowe - Montreal, Quebec Aspiring IronMan Triathlete aka CyberEyes, Rubik'S Cube | __o o E-Mail -> mailto:cyberia@cam.org | _ \<_ <\ WWW -> http://www.cam.org/~cyberia | __/\o_ (_)/(_) /> My Life's Epitome - July 15th, 1998 | swim bike run ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: karen@snowcrest.net (Karen McFarlin) Date: 18 Apr 1997 00:57:40 GMT I tried short boards around 1972 - 73 when they had hard down rails and extremely rockered noses. They were dogs. You could buy a used Weber Performer for $20. (I should've seen ahead and bought them all and stacked them away in my mother's garage.) Before going in the Army in 65, I'd only ridden boards over 9 feet. Around 76/77 I bought a 8-3 Andrini 365 at the Santa Barbera Surf Shop. It was the perfect board for Rincon. The shape was more like a longboard, with eggy rails and a square tail. It was a good down the line charger and still capable of quick turns. I loved that board - did some of my best surfing on it. My daughter rides it now - she's 21. Since 81 - I've only ridden longboards. I'd have to agree with those east coast guys, for most of your average-sized and small surf, longboards are most functional. But I've seen some younger guys rip on 6-8ft Rincon on shortboards. I just never got the hang of the little critters. I don't get a chance to surf much any more, I live in the mountains now. But my son (12) talked me into learning to snowboard. It's cool but it can't match those days back in 62 when we used to head up from Ventura to Santa Barbera and ride all the little spots like "Stanley's" along the highway. It don't last forever kids. Cairns ======== To: teacher@sccoast.net Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: headrush@lava.net (HEADRUSH) Date: 19 Apr 1997 04:14:53 GMT Madison (teacher@sccoast.net) wrote: : I am a surfer in Myrtle Beach, SC and have a 6' 6" Perfection board. The : waves around here are pretty small (4 ft. is decent) and my board doesn't : ride them that well. I was wondering if I would be better off with a : longboard, and if so, what length and type? Does a longboard ride small : waves better? What are the pros and cons? If anyone knows anything about : this, e-mail me at teacher@sccoast.net or post the reply on this newsgroup. Depending on what you want and how you ride, you can get more surfing time out of a longboard per small wave. Bigger foam = more buoncy. But you have to paddle earlier and a little farther for each wave because the board is bigger and heavier. Its like driving a cadillac. Smooth ride but you got to adjust to the wider turns and accelerate more to get in motion. Hope that helps some. ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: surffohio@aol.com (SurffOhio) Date: 19 Apr 1997 04:53:10 GMT headrush@lava.net (HEADRUSH) writes: >Depending on what you want and how you ride, you can get more surfing time >out >of a longboard per small wave. Bigger foam = more buoncy. But you have to >paddle earlier and a little farther for each wave because the board is bigger >and heavier. Its like driving a cadillac. Smooth ride but you got to adjust >to the wider turns and accelerate more to get in motion. Hope that helps some. The opposite is true. It is easier to accelerate a long board, and you can paddle latter and shorter for each wave. Surff ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: gadgetpjt@aol.com (Gadget PJT) Date: 19 Apr 1997 14:09:53 GMT >headrush@lava.net (HEADRUSH) writes: > >>But you have to paddle earlier and a little farther for each wave because the >>board is bigger and heavier. Its like driving a cadillac. Smooth ride but you >>got to adjust to the wider turns and accelerate more to get in motion. > surffohio@aol.com (SurffOhio) writes: > >The opposite is true. It is easier to accelerate a long board, >and you can paddle latter and shorter for each wave. Ahh your both talking out of your arses. ;-) Well no, your both kinda right, in a wrong sort of way. Think what mr HEADRUSH was on about was when you sit way outside and have to paddle hard to get in, just so that you can piss off all the shortboarders. Surff was nearly right too, it isn't easy to whip-turn and start paddling, due to the inertia of a big board, but once you get going you accelerate fast. Yes, Surff I too like to sit right on the spot with my big 9' 06", swivell it at the last moment, do a one-paddle take-off and squirell down standing way back, just praying that you can avoid the pearl-dive long enough to do that arch-back bottom turn that feels so good. Unfortunately I often end up sitting further out and further over, just to get priority, paddling for a virgin lump [often knee-paddling that last bit, just to get down the shallow face], then cruising past the gaggle of short-boarders smiling smugly. Another fallacy is that shortboards are faster than longboards. It ain't so, just feels like it. To extend the automobile metaphor [that seems so popular in this thead] to yet more ludricrous lengths: Shortboard: Like driving an drop-top MG down a zig-zag mountain road at 50mph [exhilarating... nay, terrifying] Longboard: Like driving a 40 tonner down the freeway at 100mph [a yawn] P.S. Why don't Americans call longboards, mals? -------------------------------------------------------------------------- Gadget [Bude, Cornwall, UK] email: gadgetpjt@aol.com A shortboarder stuck inside the body of a longboarder. -------------------------------------------------------------------------- ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: "Anton" Date: 19 Apr 1997 18:53:42 GMT > > Another fallacy is that shortboards are faster than longboards. > It ain't so, just feels like it. > Hmmm... I don't think so. Greater surface area = greater drag. I was just reading about this in a design forum somewhere. I turns out that the fastest board is actually short and fat with minimal rocker... ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: surffohio@aol.com (SurffOhio) Date: 19 Apr 1997 22:31:30 GMT Gadget writes: >> Another fallacy is that shortboards are faster than longboards. >> It ain't so, just feels like it. > >> "Anton" writes: >Hmmm... I don't think so. Greater surface area = greater drag. I was >just reading about this in a design forum somewhere. I turns out that the >fastest board is actually short and fat with minimal rocker... No, longboards are faster. Why are paddleboards 12' plus? You get a longer stroke with a longboard, so there is more power generated, and you go faster. Surff ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: "Anton" Date: 20 Apr 1997 07:25:38 GMT > > >> Another fallacy is that shortboards are faster than longboards. > >> It ain't so, just feels like it. > > > > >> "Anton" writes: > > >Hmmm... I don't think so. Greater surface area = greater drag. I was > >just reading about this in a design forum somewhere. I turns out that > the > >fastest board is actually short and fat with minimal rocker... > > No, longboards are faster. Why are paddleboards 12' plus? You get a longer > stroke with a longboard, so there is more power generated, and you go > faster. > > > Surff > You are partially right. A longboard paddles faster, but only because it planes at lower speed. I have yet to be able to paddle a 6'8" fast enough to get it to plane. You're pushing a lot of water around when you paddle a shortboard. The idea behind a paddleboard is to have a board that planes almost instantly, that's why they're 12' and who knows how thick. All that volume = low planing speed. When you catch a wave however, you now have enough speed to plane both a longboard and a shortboard. And when you're up and planing, the only force to consider is water friction (which is of course proportional to surface area). I've got a late 80's 6'4" Rusty that I like to take out every once in a while. It's 18.5" wide and it's the fastest board I've ever ridden. ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: ric@discoveryinternational.com (Ric Harwood) Date: Sun, 20 Apr 1997 20:42:18 GMT In alt.surfing, on 20 Apr 1997 07:25:38 GMT "Anton" , wrote: >> >> Another fallacy is that shortboards are faster than longboards. >> >> It ain't so, just feels like it. >> > >> >> >Hmmm... I don't think so. Greater surface area = greater drag. I was >> >just reading about this in a design forum somewhere. I turns out that >> the >> >fastest board is actually short and fat with minimal rocker... >> >> No, longboards are faster. Why are paddleboards 12' plus? You get a >longer >> stroke with a longboard, so there is more power generated, and you go >> faster. > >You are partially right. A longboard paddles faster, but only because it >planes at lower speed. I have yet to be able to paddle a 6'8" fast enough >to get it to plane. You're pushing a lot of water around when you paddle >a shortboard. The idea behind a paddleboard is to have a board that planes >almost instantly, that's why they're 12' and who knows how thick. All that >volume = low planing speed. When you catch a wave however, you now have Can you really paddle a 12' board fast enough to plane? This would be at some speed >~4knots. [ I can only paddle a kayak at that speed, and still can't get it to plane.] I would have thought that it remains a displacement craft. A long displacement craft *will* move more quickly than a short one, [c = 1.65 T ]. And as you say, the low volume of a shortboard certainly does make to hader to paddle as the board/rider are displacing more water. >enough speed to plane both a longboard and a shortboard. And when you're >up and planing, the only force to consider is water friction (which is of >course proportional to surface area). Surely weight will still be relevent? The more a board/rider combi weighs the more effort is required to lift them out of the water and keep them on the plane? >I've got a late 80's 6'4" Rusty that I like to take out every once in a >while. It's 18.5" wide and it's the fastest board I've ever ridden. Interesting thread. regards, Ric. -- European Surf forecast links and alt.surfing FAQ: http://www.discoveryinternational.com/ric/surf.htm PGP public Key ID: 0766ABE5 ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: surffohio@aol.com (SurffOhio) Date: 19 Apr 1997 22:21:13 GMT Headrush writes: >>But you have to paddle earlier and a little farther for each wave because the >>board is bigger and heavier. Its like driving a cadillac. Smooth ride but you >>got to adjust to the wider turns and accelerate more to get in motion. > surffohio@aol.com (SurffOhio) writes: > >The opposite is true. It is easier to accelerate a long board, >and you can paddle latter and shorter for each wave. Gadget writes: >>troll mode /on> >>Ahh your both talking out of your arses. ;-) >>troll mode /off> >>Well no, your both kinda right, in a wrong sort of way. >>Think what mr HEADRUSH was on about was when you sit >>way outside and have to paddle hard to get in, just so that >>you can piss off all the shortboarders. Paddling on a longboard is easier. And don't use "troll mode" to cover any mistakes, honey bunny. >>Surff was nearly right too, it isn't easy to whip-turn and >>start paddling, due to the inertia of a big board, but once >>you get going you accelerate fast. Nearly right? Hello, I did not see "whip turn" mentioned in this thread, at any time. Nor did I see it implied, my fine English Gentleman. It's easier and faster to paddle a longboard. I has spoken. Your're such a darn sweetheart, Gadget. Surff ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: gadgetpjt@aol.com (Gadget PJT) Date: 20 Apr 1997 00:34:16 GMT surffohio@aol.com (SurffOhio) writes: >Gadget writes: > >>>troll mode /on> >>>Ahh your both talking out of your arses. ;-) >>>troll mode /off> > don't use "troll mode" to cover any >mistakes, honey bunny. Score one to Gadget's troll mk. 1. ;-) -------------------------------------------------------------------------- Gadget [Bude, Cornwall, UK] email: gadgetpjt@aol.com "Too bad that all the people who know how to run the country are busy driving taxi-cabs and cutting hair." -- George Burns -------------------------------------------------------------------------- ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: tbmaddux@alumnae.caltech.edu (Timothy B. Maddux) Date: 21 Apr 1997 22:27:34 GMT I think the salient point in terms of catching waves w.r.t. longboards and shortboards is that longboards plane more easily. They don't need as much speed or as steep a wave to surf. In article <19970419140900.KAA27521@ladder01.news.aol.com>, Gadget PJT wrote: >Another fallacy is that shortboards are faster than longboards. >It ain't so, just feels like it. Neither type of surfboard is always faster than the other type, and such a discussion misses the point anyways. But, for the sake of refuting Gadget, I'll unequivocally state that in lining-up hollow waves a properly pumped shortboard is quite a bit faster than a longboard. I know this from personal experience in the rivermouth section at Rincon, having caught up to and passed many perfectly-trimmed and not-unskilled longboarders there. -- .-``'. Timothy B. Maddux, Ocean Engineering Lab, UCSB .` .`~ http://www.engineering.ucsb.edu/~tbmaddux/ _.-' '._ "From the essence of pure stoke springs all creation." ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: "Bonzer" Date: 22 Apr 1997 15:17:16 GMT This is a multi-part message in MIME format. ------=_NextPart_000_01BC4F5A.472CCAA0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit I think we need to put this thread to rest once and for all. The speed of any board is a simple function of the following: speed = mass+(weight<= or >length)/width to the 12 power*[cosign of viscosity]+(bouancy/the square root of ability)-fluid resistance factor:(tail*fin lenght/3) =%bodyfat ratio+number of tacos consumed/caloric intake Simply put (for those with less a grasp of mathematical equations than I), the fatter you are the slower the board goes :) Bonbonzer ------=_NextPart_000_01BC4F5A.472CCAA0 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable

I think we need to put this = thread to rest once and for all. The speed of any board is a simple = function of the following:

speed =3D mass+(weight<=3D or = >length)/width to the 12 power*[cosign of viscosity]+(bouancy/the = square root of ability)-fluid resistance factor:(tail*fin = lenght/3) =3D%bodyfat ratio+number of tacos = consumed/caloric intake

Simply put (for those with less a grasp = of mathematical equations than I), the fatter you are the slower the = board goes :)

Bonbonzer

------=_NextPart_000_01BC4F5A.472CCAA0-- ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: Fred Date: Tue, 22 Apr 1997 14:09:02 +0000 Bonzer wrote: > speed = mass+(weight<= or >length)/width to the 12 power*[cosign of > viscosity]+(bouancy/the square root of ability)-fluid resistance > factor:(tail*fin lenght/3) =%bodyfat ratio+number of tacos > consumed/caloric intake This "fluid resistance factor", is that how many beers it took to wash the tacos down? Fred FredNet - http://www.geocities.com/TheTropics/Shores/2303/ ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: Calvin Date: Mon, 28 Apr 1997 17:03:38 -0700 [Massive snipping for each quote, and quotes not necessarily in order] Gadget wrote: "...fallacy is that shortboards are faster than longboards." Anton wrote: "...fastest board is actually short and fat with minimal rocker..." Surff wrote: "...longboards are faster." Fred wrote: "...seems like a longboard would be slower, but..." Dagum wrote: "...its probably accurate to say that longboards trim at a faster speed than shortboards, but..." Maddux wrote: "Neither type of surfboard is always faster than the other type...." Bonzer wrote: [eqn. involving mass, wt, length, width, viscosity, bouancy(sp), ability, fluid resistance factor, fin length, bodyfat, tacos, and caloric intake, yielding the conclusion: "...the fatter you are the slower the board goes." All of these statements can be shown to at least partially correct (with the exception of Bonzer's), and Maddux's statement comes close to fully correct (but perhaps for the wrong reason), with a relatively simple numerical model of the steady-state motion of a surfboard on a breaking wave (that I constructed a number of years ago). The model uses a three-dimensional balance of the flow-induced normal and tangential forces on the bottom surface of the board, and the force of gravity acting on the surfer and board. It is based on a parametric representation of the velocity field in the face of a breaking wave, and semi-empirical equations relating the hydrodynamic lift on a low aspect ratio surface-piercing surface (e.g. surfboard) to the flow past the board, its angle-of-attack, and the design features (estimated on equations and data from appropriate literature). Heuristic equations, based on analogy with other planing surfaces, are used where specific information is not available (e.g. cross-flow, surface wetted by spray, etc.). A highly idealized surfboard is used in the calculation (i.e. a rectangular board, with no rocker, and hard edges). Input data consists of: 1. Wave slope at mean position of the wetted surface of the board. 2. Wave height (which, also estimates the local, shallow-water wave velocity) 3. Board width. 4. Total fin area. Given the position of the board on the wave (through the local wave slope), the model solves for the following outputs (under steady-state conditions, i.e. where the speed of the board is constant, and the curl is moving down the length of the wave at the same speed as the surfer and board). 1. Lateral speed of the board across the wave face (the onshore component is the same as the wave speed). 2. The wetted area of the board (not including the area wetted by spray). 3. The wettled length of the board (e.g. along the rail on the wave side). 4. The location of the center-of-pressure on the bottom of the board (i.e the trim location of the surfer on the board for those conditions). It also computes a number of other interesting factors, such as the angle-of-attack the bottom of the board makes relative to the sea surface, the magnitudes of the dynamic and static pressure forces, the tangential drag force, the wetted area, the aspect ratio of the wetted surface, etc. By carrying out the calculations at various locations on the wave face (e.g. various wave face slopes), the steady-state trim location on the face of the wave (and the associated position of the surfer on the board) that yields the maximum lateral speed across the wave face can be determined. Although the model is not sufficiently sophisticated to accurately predict the actual speeds achieved with a particular configuration, changes in the predicted speed resulting from changes in the board configuration provide an indication of the effects of various board design factors. Actually, the predicted speeds are not substantially different from actual speeds, and the predicted optimal trim location on the wave face is close to the location of expert surfers. A new, time-dependent, three-dimnesional model based on the Navier-Stokes equation is in the works, and will allow the examination of more realistic conditions, including the effects of "pumping". What the model predicts is what you would expect...different board shapes excel in different conditions. For some conditions, short and wide boards are faster, in other conditions, longer and narrower boards may be faster. These performance differences are the result of the combined effects of a variety of factors, including the aspect ratio (width/length ratio for the wetted area), method of trim on the face of the wave ("edge" trimmed, or trimmed to produce a net crossflow across the board, i.e. "fin" trimmed), etc., and can occur even in the absence of "pumping". Therefore, it is not surprising that there will be a considerable difference of opinion about what board shapes are fastest (and lots of opportunity to associate those difference with features of the board that actually have minimal, or the opposite, effect). One thing that remains to be kept in mind is that a surfboard is always a compromise. Imagine a triangle, labeled "Speed", Manueverability", and "Stability" at the three corners. A specific board design essentially represents some point within the triangle. Optimizing the board for speed compromises maneuverability and stability; optomizing for stability reduces maneuverability and speed, etc. This needs to be kept in mind when associating board shapes with board performance. In particular, in big waves, the key factor (as noted by Dagum) may not be speed, but rather stability, or "controlability"--especially in chop, and the ability to get into the wave early (i.e. long narrow boards). As regards Bonzer's statement, provided that the surfer stands upright, and the both a fat and skinny surfer have the same weight, and have the same trimming ability, the "short, fat" (read: spherical) surfer should be able to go faster than the "tall, skinny" surfer because of the reduction in the air drag. Someone (reference unknown) also stated: "The whole problem of drag is actually quite significant at the speeds attainable on a decent 8-10' wave". This is a correct statement, but too limited...it is the horizontal component of the drag force that counterbalances the forward component of the pressure force and thus limits the speed of the board at all speeds, fast or slow (the force of gravity is vertical, and does not directly affect the steady-state, i.e. horizontal, board speed). As a final note, Gadget said: "You can't go faster than the wave and who would want to?". To which I answer: Those of us who don't want to just go straight off, for you can and generally do whenever you go across the face of the wave. ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: keensurf@no.spam.cts.com (Thomas Keener) Date: Thu, 01 May 1997 08:28:26 GMT Calvin wrote: >Massive snipping... Holy moly! Real science! It looks like we might have some hard answers here, guys. I think this stuff all makes sense and, hey! What's this?: >semi-empirical equations ... Heuristic equations, >based on analogy ... A highly idealized surfboard is used in the calculation (i.e. a >rectangular board, with no rocker, and hard edges). umm, Calvin? Empirical? Heuristic? Analogy? Does that mean this model is all seat-of-the-pants WAG? Shucks. Are you having us on? -- TomK keensurf@cts.com ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: a149153@sh56.dseg.ti.com (Stewart Legler 952-5869) Date: 1 May 1997 15:03:27 GMT Thomas Keener (keensurf@no.spam.cts.com) wrote: : Calvin wrote: : >Massive snipping... : >based on analogy ...A highly idealized surfboard is used in the calculation : >i.e. a rectangular board, with no rocker, and hard edges). rectangular board, with no rocker (sounds like my chuck dent) definatly not idealized ('cept for really cool pearling endo's) stew ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: Calvin Date: Sun, 04 May 1997 11:29:19 -0700 > > Thomas Keener (keensurf@no.spam.cts.com) wrote: > : Calvin wrote: > : >Massive snipping... > : >based on analogy ...A highly idealized surfboard is used in the calculation > : >i.e. a rectangular board, with no rocker, and hard edges). > : > ...umm, Calvin? Empirical? Heuristic? Analogy? Does that mean this model is all seat-of-the-pants WAG? Shucks, Are you having us on? > Probably calling it a "WAG" is too harsh...perhaps a "SWAG" is more appropriate. To clarify: I am not aware of any empirical equations relating lift/drag for a surface piercing plate/surface in the face of a wave to the characteristics of the plate, etc. (by the way, I don't understand the dislike of "empirical" relationships--i.e. based on real measurements, vs. theory). In lieu of that information, the relationship between "lift" and: 1) angle-of-attack 2) wetted area 3) aspect ratio 4) Froude number (i.e. "planning" vs. "displacement") as used for a surfboard in the model is based on physical model studies of the lift coefficients for deep-V planning hulls, and the "ski" for the former Convair "Sea Dart" jet seaplane (also a "deep-V"). The principal "analogy"/"heuristic" part comes in adapting the "deep-V" results to a sloping wave face, and in backing out the pressure coefficient (i.e. a force directed normal to the surface of the board) from the lift coefficient cofficient (i.e. directed normal to the direction of motion)...the latter determined in the physical model studies. The analogy/assumption was made that the pressure coefficient normal to the bottom of the board on a wave face of slope, S, is essentially the the same as on the bottom of a deep-V hull with a dead-rise angle equal to arctan(S). This assumption was motivated by noting that increasing both the slope and/or the dead-rise angle produces an increase in the pressure-induced crossflow (i.e. perpendicular to the direction of motion), effectively reducing the aspect ratio, and reducing the dynamically generated pressure force (per unit angle of attack). For example, imagine a drawing with the cross-section of a deep-V hull on a flat surface of water, then rotate the drawing (including the water surface) so that the bottom of (one-side) of the hull (representing the bottom of the surfboard) is horizontal. This is assumed to be the analog of the surfboard on the sloping face of a wave (note that this, in turn, makes a number of assumptions about the static and dynamic pressure distribution within the face of the wave, and the cross-board flow on the wave side of the board). The model also presently assumes that the board is trimmed on the wave so that a line drawn across the board (from rail to rail) would be horizontal. Examination of photographs, and direct observation while riding on a wave, shows that most of the time, boards without exceedingly hard rails are not trimmed in this manner, but rather with the shore-side rail lower. This indicates that for most boards, the longitudinal axis of the board is not quite aligned with direction of motion, and that there is a cross-axis component to the flow across the board. This results in a cross-board component (directed onshore and along the face of the wave opposite to the direction of motion of the curl) of the pressure force, which is apparently offset/balanced in steady-state conditions by a cross-board component of the drag force (associated with the cross-board component of the flow) and a side loading on the fin(s). This trimming approach increases the drag force (the cross-board flow increases drag on the bottom of the board, plus there is the drag associated with the lift force on the fin), but this increase in drag is compensated to some degree by an increase in the effective aspect ratio for the wetted surface of the board (i.e. the board is "flatter" on the surface of the water), making the board more efficient at generating pressure (per unit angle-of-attack). Conversely, trimming the board "flat" (i.e. a horizontal line from rail-to-rail), reduces the wetted area, and produces a greater forward component (along the axis of the board) for the pressure force--the actual driving force--but this is offset by the reduced aspect ratio for the wetted surface, and hence less efficiency in generating pressure. My experience has been that the harder/sharper the rails, the more the board tends to be trimmed "flat"--but that is only a generalization and the shape of the board bottom (e.g. presence of "bowl", concave, fin design/area, etc.) will also affect the method of trim. Note also that the present simple model does not include the curvature in the face of the wave, nor variations in the slope of the wave face between the entry point of the rail of the board in the wave, and at the tail of the board, nor local accelerations of water within the face of the wave. The incorporation of spray drag into the calculation is also pretty "shakey" (but the process was included so the general effects of spray drag could be included in the calculation, given a guess about the fraction of the board area (from analogy with boat hulls) that is wetted by spray. Steward Legler (a149153@sh56.desg.ti.com) wrote: > rectangular board, with no rocker (sounds like my chuck dent) > definatly not idealized ('cept for really cool pearling endo's) > stew Idealized is in the eye of the beholder. From a computational standpoint, it is much easier to work with a rectangular planform and no rocker...besides the lift relationships incorporated into the model were based on this hull form. As you may recall, I mentioned about the "exclusion principle" for surfboards...you cannot optimize for speed, maneuverability, and stability simultaneously. This "idealized" board is probably closer to optimal for speed than the typical surfboard (a roughly triangular shaped board with the "pointy" end forward, and with an outline exactly matching the wetted area would be optimal for speed for a particular set of conditions, since there would be no spray drag, and the unwetted part of the board makes no contribution to the pressure force). Remember, from the standpoint of the model, the board can have nearly any shape you want (e.g. even excess nose kick) as long as that feature is not a wetted part of the board when it is in trim. It has been clearly shown by physcial studies published in the literature (i.e. tow tanks, etc.) and by my own drag measurements of surfboards and kneeboards, that for a planning hull (e.g. a surfboard trimmed on a decent wave) on a planar water surface, a hull (read: surfboard) with no rocker has the least drag (with the drag increasing as a function of L/R, where L=board (or hull) wetted length, R=radius of curvature associated with the rocker). The reason for this increased drag is also fairly easy to visualize if you recall that the longitudinal pressure distribution on the bottom of the board peaks just aft of the point of entry (greatest rate of change of momentum of the water moving by the board), and tapers off toward the tail of the board. In the case of excess rocker (or kick in the tail), the pressure on the rear portion of the board can actually be less than atmospheric (i.e. an assist/necessity for nose riding). Normally, the vertical component of the pressure force supplies most of the force offsetting the downward force of gravity on the surfer and board, so this negative pressure near the tail must be offset by a greater upward pressure near the forward portion of the board to give the same total upward force. Since the board has rocker, however, the pressure force in this forward area is directed more aft (relative to the perpendicular to the mean wetted chord), resulting in less forward component of the pressure force (to overcome the drag force)--and the board goes slower. One would expect that there will be some variations in these relationships for a "plate" on the curved surface of a wave, but the general relationship will probably still be true. I have experimented with many board shapes (planform, rocker, rails, etc.) over the years and all the boards that I have liked best have a progressively decreasing rocker, becoming essentially flat near the tail (admittedly, these are relatively short boards, none longer that about 5'8"), very hard rails (some have a sheet glass edge, ca. 1/16" thick, with no foam, for rails), and relatively wide tails. Nobody who has watched them in action has every complained that they are slow (but these design parameters do have consequences for maneuverability and especially stability). For example, my current stand-up board for small waves (also used as a kneeboard and a pseudo-bodyboard) is 4'5" long, dead flat rocker (except for nose kick) and dead flat from rail to rail with VERY hard rails. It is quite wide (23" max, 21" nose, 21-1/4" tail). All these factors maximize the efficiency in generating pressure (per unit angle of attack). It was not intended, and is not, a general purpose board, but people that have seen it in action have often commented on how well it planes/moves/glides on small, slow waves (but when it finally does stop planning, it does so with a vengeance). I hope this clarifies some of the references to "empirical", "heuristic", and "analogy" that were part of the original post, and further identifies some of the factors included in, or left out (and thus a limitiation) of the present simple model. ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: Fred Date: Thu, 01 May 1997 12:06:37 +0000 Gadget PJT wrote: > > Calvin writes: > > > As a final note, Gadget said: "You can't go faster than the wave and who > > would want to?". To which I answer: Those of us who don't want to just > > go straight off, for you can and generally do whenever you go across the > > face of the wave. > > Uuh?? Please explain [in words of not more than two syllables]. Well of course we want to go faster than the wave, that way we can do all the fun stuff...like cutbacks and off-the-lips and spinners(for all us spongers) and if you hope to make it out of the tube you'd better be going faster than the wave. Today I wasn't though...made the drop if I was lucky, then got to ride the foam in...YIPPEE! Fred FredNet - http://www.geocities.com/TheTropics/Shores/2303/ ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: karen@snowcrest.net (Karen McFarlin) Date: 24 Apr 1997 13:50:52 GMT In article <01bc4f94$f38ba2a0$3f42a7cf@dew.znet.com>, "Bonzer" wrote: > This is a multi-part message in MIME format. > > ------=_NextPart_000_01BC4F5A.472CCAA0 > Content-Type: text/plain; charset=ISO-8859-1 > Content-Transfer-Encoding: 7bit > > I think we need to put this thread to rest once and for all. The speed of > any board is a simple function of the following: > > speed = mass+(weight<= or >length)/width to the 12 power*[cosign of > viscosity]+(bouancy/the square root of ability)-fluid resistance > factor:(tail*fin lenght/3) =%bodyfat ratio+number of tacos consumed/caloric > intake > > Simply put (for those with less a grasp of mathematical equations than I), > the fatter you are the slower the board goes :) > > Bonbonzer > ------=_NextPart_000_01BC4F5A.472CCAA0 > Content-Type: text/html; charset=ISO-8859-1 > Content-Transfer-Encoding: quoted-printable > >

color=3D"#000000" face=3D"Comic Sans MS">I think we need to put this = > thread to rest once and for all. The speed of any board is a simple = > function of the following:

speed =3D mass+(weight<=3D or = > >length)/width to the 12 power*[cosign of viscosity]+(bouancy/the = > square root of ability)-fluid resistance factor:(tail*fin = > lenght/3) =3D%bodyfat ratio+number of tacos = > consumed/caloric intake

Simply put (for those with less a grasp = > of mathematical equations than I), the fatter you are the slower the = > board goes :)

Bonbonzer

> > ------=_NextPart_000_01BC4F5A.472CCAA0-- Wow, I'm impressed! (I flunked math twice, then they stuck me in the "Shop Math" class with all the Mexican guys who were in the Future Auto Body Repair Club.) But everytime the flag on the pole whipped around to off-shore, Bob Hayes and I'd jump the fence and head for the beach. Bob? Are you out there? Still among the living? You owe me twenty bucks you jerk, and I want my Morey Pope back! Cairns ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: andrew Date: Thu, 24 Apr 1997 18:49:34 -0400 Karen McFarlin wrote: > Bob? Are you out there? Still among the living? You owe me twenty bucks > you jerk, and I want my Morey Pope back! Karen, It's me Bob. You can have me anytime. a. errr b. :) ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: gadgetpjt@aol.com (Gadget PJT) Date: 23 Apr 1997 12:34:08 GMT tbmaddux@alumnae.caltech.edu (Timothy B. Maddux) writes: >But, for the sake of refuting Gadget, I'll unequivocally >state that in lining-up hollow waves a properly pumped >shortboard is quite a bit faster than a longboard. I know >this from personal experience in the rivermouth section at >Rincon, having caught up to and passed many perfectly-trimmed >and not-unskilled longboarders there. But for the sake of refuting the Mad-dog... Ahh, but that's only because they were shoulder-hopping scum-filth. Put yourself in their booties, if you had dropped in on a fat shoulder wouldn't you be going slowly? When you're in the the pocket [the fastest steepest part of the wave] wouldn't you always be the fastest chap on the wave? But for the sake of refuting myself.... I have suprised many a shortboarder, that thought I wouldn't make it around a section, only to oust him, and regain my rightful place in the pocket [but I'll admit there have been many more times when I got bogged down in the soup and not made it]. This is turning into a wonderfully pointless thread, I love it. You can't go faster than the wave, and who would want to? Oh, and yes, I can pump turn my log [but only when its at least waist high and fairly steep]. -------------------------------------------------------------------------- Gadget [Bude, Cornwall, UK] email: gadgetpjt@aol.com "The way I see it if you want the rainbow, you gotta put up with the rain. -- Dolly Parton -------------------------------------------------------------------------- ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: tbmaddux@alumnae.caltech.edu (Timothy B. Maddux) Date: 26 Apr 1997 17:57:24 GMT In article <19970423123300.IAA03420@ladder01.news.aol.com>, Gadget PJT wrote: >Ahh, but that's only because they were shoulder-hopping scum-filth. >Put yourself in their booties, if you had dropped in on a fat shoulder >wouldn't you be going slowly? Every time I've passed one of them, it's been (as I stated) in the rivermouth section at Rincon. It's fast and walled-out, with the drop-ins coming on a peak further down the line. The shortboarder drives on the wave and overtakes the trimming longboarder. E.g., longboards are not always faster than shortboards. >When you're in the the pocket [the fastest steepest part of the wave] >wouldn't you always be the fastest chap on the wave? If that were the case w.r.t. my specific example, then I should slow down as soon as I pass, placing myself farther along Gadget's hypothetical 'fat shoulder', allowing the guy with inside position to overtake me. It doesn't happen. -- .-``'. Timothy B. Maddux, Ocean Engineering Lab, UCSB .` .`~ http://www.engineering.ucsb.edu/~tbmaddux/ _.-' '._ "From the essence of pure stoke springs all creation." ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: "John Brown" <**sano96@themall.net**> Date: 29 Apr 1997 02:34:50 GMT I think most of us would prefer a longboard that instantly contracts to a shortboard upon assumption of the vertical stance. I would also like a superconducting jet engine that eliminates the need for manual paddling. And giant offshore wave generation machines. Oh, and reliable anti-shark devices. As to why us Californians don't use the term "Mals:" Chinese don't call their diet "Chinese food," do they? It's just "food." BTW, I first stood up vertical long ago at the beach where Baywatch is now filmed. It used to be a nice little wave, I guess the sandbar shifted. Now here's a question for you UK surfers: Could I satisfy my surfing urges were I to live in London for a year? Cause London rocks! If it had Hawaiian surf it would be heaven on earth. ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: Didier PARISE Date: Mon, 21 Apr 97 11:20:01 +0100 Why not going for something 'inbetween'. I own a 'mini-malibu' which is 2.3 m long (7'6"), 3 fins. Getting old and still wanting riding hollow waves,I found it the perfect compromise of maneuvrability and floatability. Anyway, as says Gary, select the right tool for the right job. Didier dparise@schamp.ccip.fr ======== Newsgroups: alt.surfing Subject: Re: Longboard vs. Shortboard From: tbmaddux@alumnae.caltech.edu (Timothy B. Maddux) Date: 23 Apr 1997 19:28:52 GMT In article <5jbkh2$api$1@kaopala.mhpcc.edu>, Gary Blumenstein wrote: [ an enjoyable post, all of which I trimmed except for: ] >... So if anything, the shortboarding experience >has served to ENHANCE my longboarding which I still >enjoy doing every once in a while. This is by virtue >of the training principle. Just like a batter who warms >up by swinging a bat with a weighted dougnut on the end. Interesting, since I have found what is in a sense the opposite to be true. Quick background: I learned to surf on a 6'8" after years of bodyboarding, now riding a 6'6" thruster. I purchased a 9'2" this summer and loved it. Small waves are fun again. Perhaps what I like best about my longboard, though, is the improvement in feel I have for my 6'6" after riding the log once or twice. It's more than just an adjustment back to a more responsive board; I'm suddenly more in tune with the rails and fins than before I rode the longboard. Maybe it's all in my head, but I get some of my best sessions on my 6'6" the day after I ride my 9'2". Longboarding has enhanced my shortboarding. -- .-``'. Timothy B. Maddux, Ocean Engineering Lab, UCSB .` .`~ http://www.engineering.ucsb.edu/~tbmaddux/ _.-' '._ "From the essence of pure stoke springs all creation." ======== Newsgroups: alt.surfing,alt.surfing.bodyboard Subject: Re: Longboard vs. Shortboard From: Fred Date: Mon, 28 Apr 1997 11:30:14 +0000 Timothy B. Maddux wrote: > Perhaps what I like best about my longboard, though, is > the improvement in feel I have for my 6'6" after riding > the log once or twice. It's more than just an adjustment > back to a more responsive board; I'm suddenly more in tune > with the rails and fins than before I rode the longboard. > Maybe it's all in my head, but I get some of my best sessions > on my 6'6" the day after I ride my 9'2". Longboarding has > enhanced my shortboarding. I get much the same feeling when I take out the longboard and then the bodyboard in the same session...it's like flying in a dream! I have a hard time paddling the bodyboard, but I really appreciate duckdiving it, and oddly enough I seem to be more in touch with the board and what it can do on the wave after riding the log...PURE STOKE! And that's on top of the stoke I've already gotten from "the beast". Needless to say, I've been a happy puppy lately. And I figure that once I get a little bored with the longboard, it will be time to get a shortboard and gain a whole new perspective. And then...a kneeboard? :-) Fred Where I Live... http://www.BrookingsOR.com/BrookingsOR/index.shtml