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Variable Rocker Tuning System - Mistral

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Created by Reflex Films > 9 months ago, 22 Jan 2016
Man0verBoard
WA, 629 posts
25 Jan 2016 9:02AM
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You lot know how I love those cowardly keyboard warrior red thumbs!! Bring em on!!!

Ps - I prefer chocolates

Man0verBoard
WA, 629 posts
25 Jan 2016 9:06AM
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Roo said...
Still one big problem that Mistral haven't addressed...where can you buy the board. They have no importer in Australia or the US currently yet they have gone to all this effort launch the VRTS. Even the in the UK and a few other European countries there are no importers or shops to buy the boards from. Without a good distribution system any product is doomed to failure. It seems this is a product driven by a marketing department that knows how to write PR BS but can't set up a distribution system. SUP and fashion seem to be the focus of most of Mistral's efforts currently.

When the original challenge flex was launched Mistral were at the top of their game, they had multiple world championships to their credit, Robby Naish on their books and were the number 1 windsurfing company. Flush with funds they launched the board yet it still failed in the marketplace. Not sure with their limited resources and distribution they can hope to do any better this time.

It's curious few people have ridden the VRTS and reported on its performance. You'd think being based out of Perth, it would have been thoroughly tested and some GPS numbers posted on it by now. If it's as good as the PR blurb you'd want as many people to try it as possible and get some buzz on the beach for it. Will be interesting to see it go head to head with one of Chris Lockwood's Mistral designs to see how effective it is.


Not launched yet

Man0verBoard
WA, 629 posts
25 Jan 2016 9:11AM
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AUS4 said...
Reflex Films said..
Hello interested Windsurfers,

Neil Scheltema has spent the last 3 years developing some new technology that I believe is going to make a lot of windsurfers very happy.

Mistral saw the potential and have jumped on board.

Neil Scheltema and myself have been collaborating with Mistral on a video to describe why this system has so much potential.

The "free Speed" category boards are done and are popping out of production as we speak. Neil is currently in Europe launching the board range and VRTS system (which has been heavily patented and protected due to how much awesome it can bring to the sport)

From my couple of hours sailing it the Prototype (which has gone into production) 64cm wide / 104 litre Free speed Board gybes better than my current wave board. Its totally ridiculous how loose it is.

The prototype board feels incredibly easy to attack speed in chop on due to the smart entry rocker , board length (slightly more water line) and auto trim / release that the VRTS delivers.

While its not aimed squarely at the racing market -I would love to see what a dedicated racer could pull off with this board as i suspect the accessible speed through bumps could be quite revolutionary. Mistral are more interested in exposing everyday freeriders and "Free racers" to a board that is fast, easy to sail and yet gybes incredibly well.

We are currently working on putting this system into some wave boards - imagine being able to flatten out or progressively add tail rocker to your wave board till it feels just right - I am confident we can get a wave board that simply does the 2 things a good wave board should - sail fast and turn well. While handling a huge range of wave sizes.

For all of us who were around in the Windtech glory days (when windtech ruled the world) Its great to see Neil boosted and blending curves with his master skills.




I dare to speculate that there will be some production demos for people to try in Australia in a month or 2.


Very bouncy ride just just like the Mistral " Challenge Flex" was.


How would it be bouncy? The tail flexes, releasing tail pressure and therefor reducing board movement.

Does the flex in your mast tip and movement in the head of your sail cause you to have a 'bouncy ride'? Nope is the answer

Man0verBoard
WA, 629 posts
25 Jan 2016 9:18AM
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hardie said...
I'll get the Mistral/Chris Lockwood issue out of the way first, Chris is a great designer and will succeed because what he designs works as intended.

Now this Variable rocker bizzness? Leaving hydrodynamic theory aside, a shock absorber system on a windsurfer is a great idea for us riders who are getting older and bodies don't work as well anymore. So, if it softens the ride without degrading performance its a bloody good idea. Neil Sch is a wise man of windsurfing and deserves some respect.

I the end the market will decide, I think the consumer will have to feel a noticeable difference to invest in the product though.

A lot of us older riders are looking for flatter and flatter water to sail on, one reason being its easier on the body, you can sail longer and enjoy more.


Hardie - gps sailors will benifit greatly..especially the gybe speed and control..that will be the deal maker right there.
I'm kind of hoping people try and attack it with theories of hydro-dynamics. That will be fun..but nowhere near as much fun as sailing these boards


Roo
784 posts
25 Jan 2016 9:28AM
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Adam they just launched the board at Boot in Dusseldorf Germany with production boards available April/May. I'll be amazed if they can set up a distribution system that quickly but their marketing/distribution might just be as incredible as the board judging by your words on it.

"JANUARY 2016Text: S. West / N. Scheltema
Design by: Neil Scheltema Product Manager MRD Windsurfing Division
Running Dates: Reveal date Saturday 23rd Jan 2016 Dusseldorf Boat Show Germany
Presumed Production Release: April / May 2016
What: FreeSpeed VRTS - VARIABLE ROCKER TRIM SYSTEM (Patent Protected)

Variations: 4 sizes 58 x 240 x 95lt, 64 x 243 x 105lt, 70 x 246 x 115lt, 76 x 249 x 125lt (larger size in pipeline)
Future: FreeWave VRTS 3 sizes"

firiebob
WA, 3147 posts
25 Jan 2016 10:23AM
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Man0verBoard said..

You don't have to touch the dial, it's a plug & play system with the option of further refinement.



My mistake, as said I haven't been able to watch the vid yet, I thought it was user adjustable

Man0verBoard
WA, 629 posts
25 Jan 2016 10:34AM
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Roo said...
Adam they just launched the board at Boot in Dusseldorf Germany with production boards available April/May. I'll be amazed if they can set up a distribution system that quickly but their marketing/distribution might just be as incredible as the board judging by your words on it.

"JANUARY 2016Text: S. West / N. Scheltema
Design by: Neil Scheltema Product Manager MRD Windsurfing Division
Running Dates: Reveal date Saturday 23rd Jan 2016 Dusseldorf Boat Show Germany
Presumed Production Release: April / May 2016
What: FreeSpeed VRTS - VARIABLE ROCKER TRIM SYSTEM (Patent Protected)

Variations: 4 sizes 58 x 240 x 95lt, 64 x 243 x 105lt, 70 x 246 x 115lt, 76 x 249 x 125lt (larger size in pipeline)
Future: FreeWave VRTS 3 sizes"


Yep I know about the show - revealed/launched - in any case the boards are in production and distribution logically will target the European spring season - as Matt says we will have Production Demo's within a couple of months[edit] from now - if I were to guess I'd suggest Southern Hemisphere distribution will be set up for August-October - pure speculation of course but that timeframe is logical and manageable.
I'd like my boards delivered with my Ka quiver - that would be convenient

Man0verBoard
WA, 629 posts
25 Jan 2016 10:36AM
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snides8 said...
Looks very interesting I would love to give it a go!
Ps I'm pretty sure Neil is the Stig


I second the notion that Neil is the Stig

Man0verBoard
WA, 629 posts
25 Jan 2016 10:41AM
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firiebob said...
Man0verBoard said..

You don't have to touch the dial, it's a plug & play system with the option of further refinement.



My mistake, as said I haven't been able to watch the vid yet, I thought it was user adjustable


It's user adjustable absolutely - just not as confusing as might appear - no more so than adjusting downhaul or outhaul. Very simple

geoITA
160 posts
25 Jan 2016 3:55PM
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Man0verBoard said..

AUS4 said...
Very bouncy ride just just like the Mistral " Challenge Flex" was.



How would it be bouncy? The tail flexes, releasing tail pressure and therefor reducing board movement.

Does the flex in your mast tip and movement in the head of your sail cause you to have a 'bouncy ride'? Nope is the answer

In my humble opinion, pressure in the tail is exactly what drives the board's nose down again after impact with the oncoming chop, with the effect of leveling the ride. Provided it's all properly designed, of course.

In the "now older" m° slalom design release it was explained that the cutouts act as "trim tabs". I understand that, when the board rides level, the slightly recessed cutout areas are disengaged from water contact; and when the tail gets pushed down, they engage with waterflow, making pressure in the tail increase (more AoA + more surface), so pushing the tail up and driving the nose down again.

A flextail such as the NS's design would still work in a similar way once the screw touches the carbon plate (so after the plate has traveled by an extent that is probably close to that of a cutout); only, in a somewhat "springy" way (by the small extent of plate travel) and with a less efficient shape (curved vs. straight; or, more curved vs. less curved); but producing less tail pressure increase while the plate still travels (compared to the not-cut-out tail portion in a rigid tail), therefore allowing for a (slightly)(?) more bouncy ride.

More, when riding with the screw engaged on the plate, one might expect some amount of negative rocker between where the screw is and the zone where the plate at rest wouldn't touch the hull. Oh well, this would level the ride even more after all.

Probably in the end the "difference" will be in the spring effect absorbing some unnecessary movement while filtering-in tail pressure increases due to larger trim variations (when actually needed); at the cost of complication, weight and possible failures.

Flex in the mast tip helps releasing pressure in (otherwise) overpowering gusts. But there is no such thing as a "gust" in the water.

geoITA
160 posts
25 Jan 2016 4:15PM
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By the way. I am looking at the m° web site and I see there is something weird. The new VRTS board is displayed by NS alone. The name of AB seems to have been erased from almost anywhere. Only a reference is left in the m° timeline, where it is said that m° windsurfing license was taken on by AB in 2008 and taken back by "Mistral red dot" in 2014. The name of AB does not appear in the "community" page, which is weird if one thinks he was the first windsurfer ever to go over 50 knots on a 500 mts course and did that on a m° production board.
I also read in the VRTS launch: "Neil Scheltema Product Manager MRD Windsurfing Division", wasn't it AB's job lately?

Mark _australia
WA, 22521 posts
25 Jan 2016 4:42PM
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geoITA said..
Flex in the mast tip helps releasing pressure in (otherwise) overpowering gusts. But there is no such thing as a "gust" in the water.


I think there is plenty - sudden sideways (fin) and up.down (hull) loads all the time.

Man0verBoard
WA, 629 posts
25 Jan 2016 5:07PM
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Mark _australia said...
geoITA said..
Flex in the mast tip helps releasing pressure in (otherwise) overpowering gusts. But there is no such thing as a "gust" in the water.


I think there is plenty - sudden sideways (fin) and up.down (hull) loads all the time.


Correct Mark - tail is loaded up when the fulcrum of the chop pushes the zone between the feet and where the dynamic between front and back foot acts as suspension.

Chop = gust in comparison but actually the mast tip is responding to the mass(body weight) connected to the boom and the sailors counter intuitive movements in response to gust, chop..and pushing the front foot which is also critical to trim and responsive to lift generated by air pressure around the board.

Geezus it's all a bit tricky eh?! Some sailors get it - some don't.

the subtle and high response flexing of this tail is so finely tuned...even thinking about it makes it less efficient

waveslave
WA, 4263 posts
25 Jan 2016 5:33PM
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Is there an internal metal spring or maybe some kind of torsion-rubber part at the 'hinge' end ?

Where the end of the adjustment screw engages with the flap ... that's definitely a wear-point.

Might need a friendly soleplate washer or something attached to the screw-end.

And the flap would need to be beefed-up on the inside face at that point of contact.

The head of the screw deckside might need a camlock lever thingy or something to prevent self-loosing/tightening,

and would need to be generous enough to grab easily with two fingers so adjustment can be done on the water.

Good luck with this latest pole-dancing gimmick.

Man0verBoard
WA, 629 posts
25 Jan 2016 5:57PM
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waveslave said...








Is there an internal metal spring or maybe some kind of torsion-rubber part at the 'hinge' end ?

Where the end of the adjustment screw engages with the flap ... that's definitely a wear-point.

Might need a friendly soleplate washer or something attached to the screw-end.

And the flap would need to be beefed-up on the inside face at that point of contact.

The head of the screw deckside might need a camlock lever thingy or something to prevent self-loosing/tightening,

and would need to be generous enough to grab easily with two fingers so adjustment can be done on the water.

Good luck with this latest pole-dancing gimmick.


There is no 'hinge' so to speak. Unless you're talking about the flap on your head releasing the unknown quantity of a drip under pressure?

waveslave
WA, 4263 posts
25 Jan 2016 6:04PM
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Man0verBoard said..

waveslave said...









Is there an internal metal spring or maybe some kind of torsion-rubber part at the 'hinge' end ?

Where the end of the adjustment screw engages with the flap ... that's definitely a wear-point.

Might need a friendly soleplate washer or something attached to the screw-end.

And the flap would need to be beefed-up on the inside face at that point of contact.

The head of the screw deckside might need a camlock lever thingy or something to prevent self-loosing/tightening,

and would need to be generous enough to grab easily with two fingers so adjustment can be done on the water.

Good luck with this latest pole-dancing gimmick.



There is no 'hinge' so to speak.


So if there's no 'hinge' (so to speak),

what's giving the flap a memory action to return flush to the bottom of the board ?

AUS4
NSW, 1260 posts
25 Jan 2016 9:08PM
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Man0verBoard said..

AUS4 said...

Reflex Films said..
Hello interested Windsurfers,

Neil Scheltema has spent the last 3 years developing some new technology that I believe is going to make a lot of windsurfers very happy.

Mistral saw the potential and have jumped on board.

Neil Scheltema and myself have been collaborating with Mistral on a video to describe why this system has so much potential.

The "free Speed" category boards are done and are popping out of production as we speak. Neil is currently in Europe launching the board range and VRTS system (which has been heavily patented and protected due to how much awesome it can bring to the sport)

From my couple of hours sailing it the Prototype (which has gone into production) 64cm wide / 104 litre Free speed Board gybes better than my current wave board. Its totally ridiculous how loose it is.

The prototype board feels incredibly easy to attack speed in chop on due to the smart entry rocker , board length (slightly more water line) and auto trim / release that the VRTS delivers.

While its not aimed squarely at the racing market -I would love to see what a dedicated racer could pull off with this board as i suspect the accessible speed through bumps could be quite revolutionary. Mistral are more interested in exposing everyday freeriders and "Free racers" to a board that is fast, easy to sail and yet gybes incredibly well.

We are currently working on putting this system into some wave boards - imagine being able to flatten out or progressively add tail rocker to your wave board till it feels just right - I am confident we can get a wave board that simply does the 2 things a good wave board should - sail fast and turn well. While handling a huge range of wave sizes.

For all of us who were around in the Windtech glory days (when windtech ruled the world) Its great to see Neil boosted and blending curves with his master skills.




I dare to speculate that there will be some production demos for people to try in Australia in a month or 2.



Very bouncy ride just just like the Mistral " Challenge Flex" was.



How would it be bouncy? The tail flexes, releasing tail pressure and therefor reducing board movement.

Does the flex in your mast tip and movement in the head of your sail cause you to have a 'bouncy ride'? Nope is the answer


Hey idiot, did you watch the video ??

Man0verBoard
WA, 629 posts
25 Jan 2016 6:08PM
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waveslave said...
Man0verBoard said..

waveslave said...









Is there an internal metal spring or maybe some kind of torsion-rubber part at the 'hinge' end ?

Where the end of the adjustment screw engages with the flap ... that's definitely a wear-point.

Might need a friendly soleplate washer or something attached to the screw-end.

And the flap would need to be beefed-up on the inside face at that point of contact.

The head of the screw deckside might need a camlock lever thingy or something to prevent self-loosing/tightening,

and would need to be generous enough to grab easily with two fingers so adjustment can be done on the water.

Good luck with this latest pole-dancing gimmick.



There is no 'hinge' so to speak.


So if there's no 'hinge' (so to speak),

what's giving the flap a memory action to return flush to the bottom of the board ?


That would be the temporary elongation of the fibres within the epoxy matrix

Man0verBoard
WA, 629 posts
25 Jan 2016 6:12PM
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AUS4 said...
Man0verBoard said..

AUS4 said...

Reflex Films said..
Hello interested Windsurfers,

Neil Scheltema has spent the last 3 years developing some new technology that I believe is going to make a lot of windsurfers very happy.

Mistral saw the potential and have jumped on board.

Neil Scheltema and myself have been collaborating with Mistral on a video to describe why this system has so much potential.

The "free Speed" category boards are done and are popping out of production as we speak. Neil is currently in Europe launching the board range and VRTS system (which has been heavily patented and protected due to how much awesome it can bring to the sport)

From my couple of hours sailing it the Prototype (which has gone into production) 64cm wide / 104 litre Free speed Board gybes better than my current wave board. Its totally ridiculous how loose it is.

The prototype board feels incredibly easy to attack speed in chop on due to the smart entry rocker , board length (slightly more water line) and auto trim / release that the VRTS delivers.

While its not aimed squarely at the racing market -I would love to see what a dedicated racer could pull off with this board as i suspect the accessible speed through bumps could be quite revolutionary. Mistral are more interested in exposing everyday freeriders and "Free racers" to a board that is fast, easy to sail and yet gybes incredibly well.

We are currently working on putting this system into some wave boards - imagine being able to flatten out or progressively add tail rocker to your wave board till it feels just right - I am confident we can get a wave board that simply does the 2 things a good wave board should - sail fast and turn well. While handling a huge range of wave sizes.

For all of us who were around in the Windtech glory days (when windtech ruled the world) Its great to see Neil boosted and blending curves with his master skills.




I dare to speculate that there will be some production demos for people to try in Australia in a month or 2.



Very bouncy ride just just like the Mistral " Challenge Flex" was.



How would it be bouncy? The tail flexes, releasing tail pressure and therefor reducing board movement.

Does the flex in your mast tip and movement in the head of your sail cause you to have a 'bouncy ride'? Nope is the answer


Hey idiot, did you watch the video ??




I think that comment just put you in the sin bin

waveslave
WA, 4263 posts
25 Jan 2016 6:16PM
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Man0verBoard said..

waveslave said...

Man0verBoard said..


waveslave said...










Is there an internal metal spring or maybe some kind of torsion-rubber part at the 'hinge' end ?

Where the end of the adjustment screw engages with the flap ... that's definitely a wear-point.

Might need a friendly soleplate washer or something attached to the screw-end.

And the flap would need to be beefed-up on the inside face at that point of contact.

The head of the screw deckside might need a camlock lever thingy or something to prevent self-loosing/tightening,

and would need to be generous enough to grab easily with two fingers so adjustment can be done on the water.

Good luck with this latest pole-dancing gimmick.




There is no 'hinge' so to speak.



So if there's no 'hinge' (so to speak),

what's giving the flap a memory action to return flush to the bottom of the board ?



That would be the temporary elongation of the fibres within the epoxy matrix


Ok wiseguy,

so how is the flap attached to the bottom of the board ?

Man0verBoard
WA, 629 posts
25 Jan 2016 6:21PM
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waveslave said...
Man0verBoard said..

waveslave said...

Man0verBoard said..


waveslave said...










Is there an internal metal spring or maybe some kind of torsion-rubber part at the 'hinge' end ?

Where the end of the adjustment screw engages with the flap ... that's definitely a wear-point.

Might need a friendly soleplate washer or something attached to the screw-end.

And the flap would need to be beefed-up on the inside face at that point of contact.

The head of the screw deckside might need a camlock lever thingy or something to prevent self-loosing/tightening,

and would need to be generous enough to grab easily with two fingers so adjustment can be done on the water.

Good luck with this latest pole-dancing gimmick.




There is no 'hinge' so to speak.



So if there's no 'hinge' (so to speak),

what's giving the flap a memory action to return flush to the bottom of the board ?



That would be the temporary elongation of the fibres within the epoxy matrix


Ok wiseguy,

so how is the flap attached to the bottom of the board ?


Screws. Are you a carpenter?

waveslave
WA, 4263 posts
25 Jan 2016 6:23PM
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Select to expand quote
Man0verBoard said..

waveslave said...

Man0verBoard said..


waveslave said...


Man0verBoard said..



waveslave said...












Is there an internal metal spring or maybe some kind of torsion-rubber part at the 'hinge' end ?

Where the end of the adjustment screw engages with the flap ... that's definitely a wear-point.

Might need a friendly soleplate washer or something attached to the screw-end.

And the flap would need to be beefed-up on the inside face at that point of contact.

The head of the screw deckside might need a camlock lever thingy or something to prevent self-loosing/tightening,

and would need to be generous enough to grab easily with two fingers so adjustment can be done on the water.

Good luck with this latest pole-dancing gimmick.





There is no 'hinge' so to speak.




So if there's no 'hinge' (so to speak),

what's giving the flap a memory action to return flush to the bottom of the board ?




That would be the temporary elongation of the fibres within the epoxy matrix



Ok wiseguy,

so how is the flap attached to the bottom of the board ?



Are you a carpenter?


Why do you ask ? ^^^

Ian K
WA, 4055 posts
25 Jan 2016 6:30PM
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Select to expand quote
waveslave said..

Man0verBoard said..


waveslave said...


Man0verBoard said..



waveslave said...



Man0verBoard said..




waveslave said...














Is there an internal metal spring or maybe some kind of torsion-rubber part at the 'hinge' end ?

Where the end of the adjustment screw engages with the flap ... that's definitely a wear-point.

Might need a friendly soleplate washer or something attached to the screw-end.

And the flap would need to be beefed-up on the inside face at that point of contact.

The head of the screw deckside might need a camlock lever thingy or something to prevent self-loosing/tightening,

and would need to be generous enough to grab easily with two fingers so adjustment can be done on the water.

Good luck with this latest pole-dancing gimmick.






There is no 'hinge' so to speak.





So if there's no 'hinge' (so to speak),

what's giving the flap a memory action to return flush to the bottom of the board ?





That would be the temporary elongation of the fibres within the epoxy matrix




Ok wiseguy,

so how is the flap attached to the bottom of the board ?




Are you a carpenter?



Why do you ask ? ^^^


No hinges, just a bendy bit of carbon fibre composite. Could get to the stage of needing a whole swag of bolt on tail sections for various conditions. Soft flex, medium flex, hard flex, constant curve, soft top..... If it makes the ride softer, can't see why it won't, the old blokes will lap it up.

geoITA
160 posts
25 Jan 2016 6:32PM
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Man0verBoard said..


Mark _australia said...


geoITA said..
Flex in the mast tip helps releasing pressure in (otherwise) overpowering gusts. But there is no such thing as a "gust" in the water.




I think there is plenty - sudden sideways (fin) and up.down (hull) loads all the time.




Correct Mark - tail is loaded up when the fulcrum of the chop pushes the zone between the feet and where the dynamic between front and back foot acts as suspension.

Chop = gust in comparison but actually the mast tip is responding to the mass(body weight) connected to the boom and the sailors counter intuitive movements in response to gust, chop..and pushing the front foot which is also critical to trim and responsive to lift generated by air pressure around the board.

Geezus it's all a bit tricky eh?! Some sailors get it - some don't.

the subtle and high response flexing of this tail is so finely tuned...even thinking about it makes it less efficient



In my experience, relative board - water speed varies very little (in both direction and quantity) compared to what happens in a gust. And, most of all, changes are due to variations in board trim (comparable to sheeting in more or less, and/or rake angle changes) but have nothing to do with changes in fluid speed (in both direction and quantity) as happens with a wind gust.
Passing fom a lull to a gust may mean wind changing from say 15 knots to 25. If you assume the board is going on a beam reach at 27 knots, this means relative (apparent) speed changes from 31 to 37 knots (plus there also is a direction change) in few seconds. I seriously doubt that hitting chop may cause anything like that in waterflow changes around board and fin. Expecially when you consider chop hit will give the board a brief impulse, while a gust may last for a few seconds. The trim change due to chop hit will cease in very short time leading (usually) to board and fin having a trim that is not constant, but quickly and slightly variating around a "mean" trim; while a gust, if not dealt with properly, has enough time to alter the ride by much (or to stop it).

It's also funny how until now we used to consider carbon built being superior because of its characteristics of quick response to inputs due to water state, and now are considering absorbing such inputs instead.

Chris 249
NSW, 3376 posts
25 Jan 2016 9:45PM
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Man0verBoard said.. Most top shapers will know(I'm not one..I was taught by one) that the part of the tail behind the fin is useless for trim or speed - it's just unwanted drag - and it's only role is to prevent ventilation to the trailing edge of the fin and the resultant cavitation and spin-out.


Why is that so? Surely the position of the fin has little to do with the water flow over the tail of the board behind the fin? Surely it's not as if the water gets past the fin and then says "whoopy, now we've done all the work we can just party" or something like that?

Ian K
WA, 4055 posts
25 Jan 2016 6:55PM
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geoITA said..





In my experience, relative board - water speed varies very little (in both direction and quantity) compared to what happens in a gust. And, most of all, changes are due to variations in board trim (comparable to sheeting in more or less, and/or rake angle changes) but have nothing to do with changes in fluid speed (in both direction and quantity) as happens with a wind gust.
Passing fom a lull to a gust may mean wind changing from say 15 knots to 25. If you assume the board is going on a beam reach at 27 knots, this means relative (apparent) speed changes from 31 to 37 knots (plus there also is a direction change) in few seconds. I seriously doubt that hitting chop may cause anything like that in waterflow changes around board and fin. Expecially when you consider chop hit will give the board a brief impulse, while a gust may last for a few seconds. The trim change due to chop hit will cease in very short time leading (usually) to board and fin having a trim that is not constant, but quickly and slightly variating around a "mean" trim; while a gust, if not dealt with properly, has enough time to alter the ride by much (or to stop it).

It's also funny how until now we used to consider carbon built being superior because of its characteristics of quick response to inputs due to water state, and now are considering absorbing such inputs instead.


I think there's a reason some sailors have a dislike for stiff fins. Here's an old video to give a feel for what's going on under the board. The first 5 minutes should do.

gavnwend
WA, 1366 posts
25 Jan 2016 6:57PM
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This topic is starting to sound to optimistic with a lot of pessimistic chatter.l think we are all left in the gutter with some of us looking at the stars.lets wait for the board to gets some demo's and reveiws by experts.

Man0verBoard
WA, 629 posts
25 Jan 2016 7:00PM
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Select to expand quote
geoITA said...
Man0verBoard said..


Mark _australia said...


geoITA said..
Flex in the mast tip helps releasing pressure in (otherwise) overpowering gusts. But there is no such thing as a "gust" in the water.




I think there is plenty - sudden sideways (fin) and up.down (hull) loads all the time.




Correct Mark - tail is loaded up when the fulcrum of the chop pushes the zone between the feet and where the dynamic between front and back foot acts as suspension.

Chop = gust in comparison but actually the mast tip is responding to the mass(body weight) connected to the boom and the sailors counter intuitive movements in response to gust, chop..and pushing the front foot which is also critical to trim and responsive to lift generated by air pressure around the board.

Geezus it's all a bit tricky eh?! Some sailors get it - some don't.

the subtle and high response flexing of this tail is so finely tuned...even thinking about it makes it less efficient



In my experience, relative board - water speed varies very little (in both direction and quantity) compared to what happens in a gust. And, most of all, changes are due to variations in board trim (comparable to sheeting in more or less, and/or rake angle changes) but have nothing to do with changes in fluid speed (in both direction and quantity) as happens with a wind gust.
Passing fom a lull to a gust may mean wind changing from say 15 knots to 25. If you assume the board is going on a beam reach at 27 knots, this means relative (apparent) speed changes from 31 to 37 knots (plus there also is a direction change) in few seconds. I seriously doubt that hitting chop may cause anything like that in waterflow changes around board and fin. Expecially when you consider chop hit will give the board a brief impulse, while a gust may last for a few seconds. The trim change due to chop hit will cease in very short time leading (usually) to board and fin having a trim that is not constant, but quickly and slightly variating around a "mean" trim; while a gust, if not dealt with properly, has enough time to alter the ride by much (or to stop it).

It's also funny how until now we used to consider carbon built being superior because of its characteristics of quick response to inputs due to water state, and now are considering absorbing such inputs instead.


I can only answer your last question as, yes

Man0verBoard
WA, 629 posts
25 Jan 2016 7:23PM
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No Ian K - that's not it the master plan - it's about simplification

Man0verBoard
WA, 629 posts
25 Jan 2016 7:25PM
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Select to expand quote
Chris 249 said...
Man0verBoard said.. Most top shapers will know(I'm not one..I was taught by one) that the part of the tail behind the fin is useless for trim or speed - it's just unwanted drag - and it's only role is to prevent ventilation to the trailing edge of the fin and the resultant cavitation and spin-out.


Why is that so? Surely the position of the fin has little to do with the water flow over the tail of the board behind the fin? Surely it's not as if the water gets past the fin and then says "whoopy, now we've done all the work we can just party" or something like that?


Chris I've actually heard it say exactly that!



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