Pintails

[wanto]

Luv the way the rounded pins cut tight and hang in when it’s punchy and round.
Hate the lag that accompanies rounded pins when milking for speed

I’ve had more frustrating sessions on my rounded pins than my squares, but most of my best sessions have been on rounded pins
:?
every quiver needs one....or three..

hano, insightful and exactly right.

[pridmore]

My general theory is that the tail probably has only a small influence on the overall feel of the board

Yeahbut.

Tail shapes change the entire outline behind the wide point.

The outline curve on a round pin, compared with say a squash, is different well forward from the actual "tail".

Changing that curve changes other curves: where the concave falls in and out, where the rocker moves, how the rail tapers.

The change in tail width changes how fins work.

In other words, change the tail and you change almost the whole board.

I reckon all committed surfers go through phases with tail shapes, you kinda get hooked on a feeling of a swallow, then unconsciously get bored by it, and suddenly the squash is the New Big Thing for you, then you get bored with that, etc etc.

fong: Probably KS's all time best surfboard ever was a 6'1" Simon Anderson round pin, which he rode in competition from 2004 to 2007 -- a three year run. Won two J-Bays, a Bells and numerous heats in other locations on that thing.

well said, I know I went thru phases and then when something wasnt feeling right, I would go back to the old faithful design ( which for me was a 6'3 x 19 x 2 1/2" rounded pin ) , but always toyed with diff tail shapes even assymetricals...the Simon KS loved was nicknamed ' Brown Beauty', I think, coz he had it for sooo long ,that the thing was going brown...the tail shape doesnt really change your whole board, more the pod measurement, but the curve from the tail measurement to the pod will differ dramatically with the slightest change to the pod width, the actual tail shape will alter performance for sure, but think that curve in the rail leading to the pod is critical to how the board performs ( along with rocker and other stuff too, so many variables...)

[ric_vidal]

My general theory is that the tail probably has only a small influence on the overall feel of the board

Yeahbut.

Tail shapes change the entire outline behind the wide point.

The outline curve on a round pin, compared with say a squash, is different well forward from the actual "tail".

Changing that curve changes other curves: where the concave falls in and out, where the rocker moves, how the rail tapers.

NC, point taken in the example, but I don't know that that is that so, and that is a lot of thats... well least in my example

I’m not overly sure of Rich’s fin placement, but I think the back fin is way forward (5 1/2" ?) and he certainly has some specific marks he likes for his own boards tail width.

As a quicky, this is a pintail round tail combined, not what I would call a marked change in the rail outline bar the obvious.

Sorry Rich, it ain’t PURE.

[RichQ]

Hey Ric, put the pin inside the roundedpin &make them the sme length to see more of an outline change ......back fin 5"ish ...front fins12.5"ish....depends on tail widths......magic numbers ,grasshopper.

[oldman]

I understand what you are all saying about the tail changing the other dimensions of the board. I suppose my argument back would be that it can just as easily be considered the other way around, i.e. the rest of the board dictates the tail.

That then becomes a chicken and egg argument. I could then ask whether you build a board from top to tail, back to front, or side to side, but no answer would really be correct would it, because you start of with a plan shape (don't you?)

Nobody does a 'freehand' board do they, except maybe Ric?

[AlbyAl]

Wow, interesting reading all these different confabulations on rail lines.

Mr Webber once explained to me his theory (now don't all laugh - I know he's explained theories to everyone) on curves (no not breast curves) - and if you look at the diagram above you can see that it approximates y= x squared: ie, a parabola where the vertical measurement (the y axis) is squared for each horizontal or x measurement. Both the nose and tail measurements approximate variations on basic parabolas meeting at the widepoint.

Webber thought this was the 'natural' curve of surfboards - one for the nose, one for the tail. The rockers, foil curves and the variations in volume could also be expressed by such mathematical formulae, and related to each other.

In other words, surfboards can be summed up by a small number of mathematical expressions that can be related to each other, suggesting the possibility that boards can be designed and varied by varying such mathematical formulae. I took this to mean that all the decades of shaving a bit here, scraping a bit there might fall by the wayside as designers pull out a 'stock' of formulae and hey presto ...

Mad perhaps! Even arrogant and suggesting even more uniformity in the craft. But there's something about the smooth progression about one of those elliptical (round pin) tails that has the nerd in me all sweaty. Look at the logical progression! Admire the rational! View the Parthenon of surfboards!

OK - now throw stuff.

[oldman]

rockers, foil curves and the variations in volume could also be expressed by such mathematical formulae, and related to each other.

I'm with you Al. Maths is a hybrid between science and philosophy and art.

I'm thinking that what the shaper puts in, apart from his expertise, is the spirit.

I think maths might one day reach into that as well.

[AlbyAl]

rockers, foil curves and the variations in volume could also be expressed by such mathematical formulae, and related to each other.

I'm with you Al. Maths is a hybrid between science and philosophy and art.

I'm thinking that what the shaper puts in, apart from his expertise, is the spirit.

I think maths might one day reach into that as well.

Really?? I guess if we think of mathematics from the Realist perspective: it is IN the universe, not just a human construction - then Mad Mr Webber thinking of 'natural' curves is savvy. I bet waves have a discrete range of mathematical expressions tied to their physics - water, gravity, motion etc - and therefore surfcraft and human bodies atop are also a discrete range of physical possibilities (even if pretty wide). Therefore - and this is a nice thought - both mathematical, and yet, if you like, also spiritual - the deeper logic of surfcraft must integrate with the logic of waves - and in so doing we recapitulate something of the physical order of the universe, its underlying ratios and relations, which we, as creatures of the cosmos intuite through the very arcs we travel.

Now, where did I put that bong - oh, yeah, next to the tie-dye T-shirts and pile of Vegetarian Monthly mags. Ffffft - OK - next deep question to solve?

[mustkillmulloway]

Nobody does a 'freehand' board do they, except maybe Ric?

tiger share with me a idea...( and if he wishes me not share with others i'll delete the post)

the prefect board for any individual must be asymmetrical

because we surf differently front side too backside

i tried it...and it was fast....conditions and fitness saw end test

but the theory....i don't doubt is true

[Quangers]

Just a matter of playing around with the cos and sin eh?

[ric_vidal]

Nobody does a 'freehand' board do they, except maybe Ric?

No, Rich is the same, sure there are plenty of others.

Hey Ric, put the pin inside the roundedpin &make them the sme length to see more of an outline change

Yeah piss poor example, glad we bumped into each other to work out the math...



For point of the the exercise, Rich works it more like this. Establish length, width and 12" widths for nose and tail. Join the dots and only the tail area from the 12" mark back will be different to accommodate WHATEVER tail type. How’s them apples, Rich?

Pssst, red ones are faster!

[RichQ]

Nice job, Riccles.....forget theories, Pintails just LOOK cool....Gee Wizz, surfboards are neato!

[tiger]

Nobody does a 'freehand' board do they, except maybe Ric?

tiger share with me a idea...( and if he wishes me not share with others i'll delete the post)

the prefect board for any individual must be asymmetrical

because we surf differently front side too backside

i tried it...and it was fast....conditions and fitness saw end test

but the theory....i don't doubt is true

Yes Fongo, assymetry is where it's at!! But that's just another piece in the massive puzzle of board design.

The variables in play here are vast beyond comprehension. Some of the more obvious ones are what kind of waves a board will be surfed in, fitness levels of rider, and as mentioned foot placement and actual physical mechanics of how a certain person approach's and performs different manouevres.

Sorry if I'm not really adding anything to the thread as such, There's just too much detail and I'm a really crap typer and can't summarise it. Much easier to just rant with beer in hand.

But I will say again, and Ric won't like it. In garden variety good surf, on say a beachbreak in which you will be surfing in both directions, everyones perfect board would be assymetrical.

[Nick Carroll]

Webber thought this was the 'natural' curve of surfboards

Yeah well you're talking about a man who thinks surfboards are sex objects.

Just as an exercise for all your brains:

If pintails are "faster", why are most modern towboards cut-off flat swallows, squares or semi bat-tails?

You have 60 seconds.

[RichQ]

Pintails arent "faster" ...I think speed comes from a combo of rocker/concave/planshape & once again, the rider on top. Oh, &the wave too. With tow boards its lengnth vs. outline...plus tow boards dont need to generate speed as much as a regular short board...DING! times up...bugger.

[ric_vidal]

But I will say again, and Ric won't like it. In garden variety good surf, on say a beachbreak in which you will be surfing in both directions, everyones perfect board would be assymetrical.

On the contrary, Tigger I think it makes perfect sense, I’ve just limited my asymmetry to finstallation, well so far, the day isn’t over.

[wanto]

If pintails are "faster", why are most modern towboards cut-off flat swallows, squares or semi bat-tails?

the rail curve is straight - think the curve of a 10 foot gun cut down to a 6 foot tow board - the tow board is also super narrow to achieve this.

as all turns are high speed, there's no need for roundness through the tail, as the water is always flying off the end. and the less resistance to sinkage the better therefore the less surface area back there the better.

a bat tail might be the other close fit, but i've always seen them as a stylised swallow anyway.

not sure if i've explained it very well (60 seconds - my fingers hurt ) but i think i kind of get it.

[Surfin Turf]

technical detail asside as it is certainly NOT my special subject ... and not within 60 seconds

I am a rounded pin rider ... and for anyone who is confusing pins for rounded pins ... this is a rounded pin ....


anyways ... I have found through riding different boards that 'the more rail the faster' ... elabiration: like a square tail or swallow tail has more (straightish) rail and seems to go faster in a straight line, and the rounded pin and pin tails are a tad slower and you rely on repositioning to generate speed ... but, I find the rounded pin more manouverable in that it doesn't slide about like a square tail, and holds firmer in a power turn ....

my larger wave board is similar to the pic above but a bit more "pinny" and less width in the tail which makes it tighter to turn ... that may be partly due to the feet positioning because of the narrower tail width as discussed by RQ ...

I could be talkin' out my arse here but like I said this is an observation from riding different board types rather than having any credible technical knowledge ...