Is the volume really necessary?

What works & what doesn't and in what type of conditions. Got a "secret" only you and your shaper know???? Post it here... we can keep it quiet ;-)

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crox
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Post by crox »

Hi EQ, Unless you can answer this -

"If I took your board & only removed foam from your board that had no hydrodynamic effect while riding, in other words that did not get immersed or interact with the water, why would it bog more easily?"

Then your post is simply repeating what you have already said and does not further the discussion.
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Post by analbirth »

So sorry Crox, i only just came onto this thread toward the last couple of pages & only skimmed over the earlier ones, i'll shut up now :oops:
once you've had black you'll never go back!!!
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eqKneelo
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Post by eqKneelo »

Kneeboards arent boats... you might be combinding principles of planning hulls and displacement hulls.

Kneeboards don't float. Most guys sit up to their stomachs or even their chests when they sit om their boards.

Water Ski's don't float either.

If I'm water skiing behind Big Fred's boat and he drops his beer and takes his hands off the throttle, I will start to sink. My power source has faded. If I'm on ski's that have more float I can at least plane until he gets another beer.

A board with proper floation will allow you to plane at maximum speed when the waves energy has dropped below 100%. A proper board with proper floation will allow you to keep the area of your board that interacts with the wave ABOVE the water and not sink below the rail line when the wave isn't offering enough power to stay afloat.

Not repeating myself... reminding you that im not conceding the point until i see proof. :wink:
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Post by crox »

Hi EQ. I'm afraid that doesn't answer the question...& there is a lot of repetition in there....however I've already posted the answers to yours -

" If the power source fades to the point at which your board is fully underwater & still somehow gliding along, I salute you sir!
I feel that the drag from your knees & deckpad might have an overriding impact at that point!"

"A factor to consider is that kneeboards carry a lot more rail
volume than performance shortboards. They have developed that way as a result of two things. We are able to apply a lot more power to the rail
with our knee placement & we also need to keep our knees out of the flow of water.....which we do as a result of that rail volume.
Therefore we do not bury the board to the depth [towards the stringer] a performance shortboarder does & if we did, we would be instantly aware
of knee drag & the stalling effect."

You said - "A board with proper floation will allow you to plane at maximum speed when the waves energy has dropped below 100%. A proper board with proper floation will allow you to keep the area of your board that interacts with the wave ABOVE the water and not sink below the rail line when the wave isn't offering enough power to stay afloat."

To suggest that extra foam on the stringer will do that is completely illogical.

I don't need to provide proof, it is simply a matter of logic and a basic design principle...this is quantifiable, unlike video evidence which would be very pilot dependent & subjective. I like to deal in facts.
Last edited by crox on Sat Oct 18, 2014 10:59 pm, edited 1 time in total.
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Post by eqKneelo »

To suggest that extra foam on the stringer will do that is completely illogical.

I don't need to provide proof, it is simply a matter of logic and a basic design principle...this is quantifiable, unlike video evidence which would be very pilot dependent & subjective. I like to deal in facts.
Your "facts" are hypothetical.
Cool ideas. Never seen proof the are superior when it comes to Kneeboard Design.
"Fantasy Boards ridden by Unicorns"
:P

My "facts" are based in video evidence, judged contest results, eyewitness accounts, and decades of R&D by the worlds best surfers and shapers with anything and everything at their disposal.

That quote was directed at me by another KSUSA MEMEBER who refused to accept the reality that "actual surfing" trumps "theoretical Surfing" until proven otherwise. 8)
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Post by crox »

EQ said - "Not repeating myself... reminding you that im not conceding the point until i see proof."

We know that 1+1 = 2 .....but we don't need a couple of wooden blocks to visually verify it.

The answer to this -

"If I took your board & only removed foam from your board that had no hydrodynamic effect while riding, in other words that did not get immersed or interact with the water, why would it bog more easily?"

Is simple, it can't.

Nothing needs to be proved....just understood.
"All we are saying, is give knees a chance"
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Post by crox »

Unfettered by affiliation or
blinded by partisan propensities lies the
bare beautiful bones of unadulterated design, not competing with the contemporary or concerned with what is, but what is yet to come.
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Post by Headwax. »

analbirth wrote:So sorry Crox, i only just came onto this thread toward the last couple of pages & only skimmed over the earlier ones, i'll shut up now :oops:
ha ha analbirth, skimming is good :)

the trick is you say - "I support the guys who have already said this: "then insert what you are going to say"

:)

and so, personally I support the guys who have already said this :

random thoughts

1) To me foam/bulk just causes excess inertia to stop you changing track

2) I've never seen a good boogie boarder bog down. Drawing the conclusion that ...

3) I've been riding boards with excess concave since 2000. The excess concave takes a lot of foam out of the board. They don't bog down. The boards are a 'normal' thickness. I think I'm up to 15 mill concave now - cant recall and the board is down stairs - too far to walk.

4) If your rail is too thin so that it acts like a fin rather than a hull it will bog when you rail to rail transfer. ie make it harder to go from one turn t'other.

5) For me thicker boards bounce more.

6) Board with a thicker rail in one part can pivot on that point - so makes your turns tighter - with other drawbacks

as Frank Williams once said to a mate of mine as we watched him shape his board in HB factory circa 76 - if it's a choice between thickness and width - go wider.

random thoughts, hope you are all well, almost surf here today :(

here's a nice film I found today

the legend frank latta by the legendary steve core

https://www.youtube.com/watch?v=hvdXkmb1dZs
crox
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Post by crox »

analbirth wrote:So sorry Crox, i only just came onto this thread toward the last couple of pages & only skimmed over the earlier ones, i'll shut up now :oops:
Not to worry AB, we all do it.

New posters having skimmed can miss out on the salient points & muddy the waters that had been made clear.

Unfortunately some moderation is needed or the thread ends up with all the informative quality of a Chinese whisper.

I wondered if you were going to pop in Headwax :D
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Post by Headwax. »

oh I wanted to type something but my password I can never remember :)
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Post by crox »

Imagine trying to do this on the average kneeboard....& what an asset it would be - http://www.theinertia.com/surf/john-joh ... -no-other/
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Post by MJ »

Speaking of skimming!

As i've only skimmed this page....

http://www.youtube.com/watch?v=2Cu0VnsWNTI

http://www.youtube.com/watch?v=1DdY4Y4pu-0

http://www.youtube.com/watch?v=FTiiHPOnZeY

Further to these vids and IMHO volume/positive buoyancy is a function of catching and staying on the wave. Once a planing water craft is on the plane, be it a surf craft, yacht or power boat the critical factors are the power source and the nature of the hull that is in contact with the water not necessarily its size/volume. Bogging only occurs when the power source is inadequate to keep the vehicle planing. Because these two factors are mutually inclusive you need to talk about increases or reduction of volume in terms of the power source/wave size being considered and the weight of the cargo. The absurd extremities of these examples I think highlight this.

Also I found out about this in the small waves at Kiama where my weight on volume in front of wave power coefficient was all wrong!

Does that make sense or have I missed the point??
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Post by crox »

Skimming is bad!
It makes sense but you've also missed the point.
The question is....where does the foam need to be to create the buoyancy required once up & riding & can foam be removed from areas of the board without increasing the tendency to bog. This I answered above -

The answer to this -

"If I took your board & only removed foam from your board that had no hydrodynamic effect while riding, in other words that did not get immersed or interact with the water, why would it bog more easily?"

Is simple, it can't.
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Post by Dunc »

Unless the water spills in to the area that has had the foam removed and gives it neutral buoyancy. In a theoretical world this would never happen but in the real world this would happen on the first test surf. Isn't this what the shoe was all about? http://www.surfresearch.com.au/00000195.jpg

I think MJ sets it out pretty nicely.
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Post by Dunc »

The dished deck shots you just posted look great and I absolutely agree that losing volume that way is sensible.
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