decrep, you're probably right- anything less than perfect Justin will probably just use his formula gear in the surf anyway

Dont get into a war of "who sails more" with me , there arent too many people round here that sail more- apart from vando who lives on his sailboard. But you are right I only sailed 3 days last week, lazy me.

Lazy me no. 2 i've still not finished the wizzard , i'd paint it today if it wasnt bloody raining. The speed board might be finished by 2020. Have no fear mate i'll come up with you some time and have a good old time slogging through the surf, and my fin box will still be in the board at the end of the day

Aaah the hyper, well i'm still not sure i've made the right decision. Hyper's arent without their faults/ideals but neither is the SX or any board, there is always some compromise to be made. I will only know for sure when the next race happens, and when vando gets his board back. In flat conditions though the hyper is hard to beat for a board of that width and weight for volume for sail size I didnt plane that late on it.

Damn you Gestalt, you know the seeds of unhappiness with it were sewn at the Redcliffe wanderers meet. I do however have a fair idea of how to make it better and I will definately be keeping measurements from the hyper. How can I be overly critical of a board which moved me from mid fleet to mixing it with the best? You want it Justin? It's still for sale and maybe you can start slalom racing. Oh and I dont believe I ever told anyone that it was the best board under the sun.

robby is right, sometimes you gotta stop and watch those better than you though.

Mark,

at least you got to go out at the redcliffe wanderers meet. i sat nervously on the beach looking out in case anyone got in trouble. i was a little concerned....

i think that is the first time i have seen you do the walk of shame [}:)] but if you take a hyper out in 2 foot breaking waves i guess there will be trouble.

the funniest thing was watching vando doing nearly 40 knots on his warp through the same swells and then launching 4 foot in the air trying to tame the beast during a laydown gybe in the shorey.

hehe, u forgot dat was d day i had my 10m out with a super small fin. hav u ever ran dat size sail on ur hyper, which is bigger than mine? i was d only one on the plane, just couldnt get up back up wind!

quote:

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Originally posted by mkseven

Did I walk? I remember padi walking the length of the beach almost after he couldnt tame his hyper

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It's so hard to generalise, about what works?

When I was up in Gero last year Mark Stone was up there, StoneSurf Design and the Starboard crew were up there Tiesda Zou, and they were talking about board adjustments of 1 mm here and there, that were making big performance changes, coz that is what the market was demanding.

Every 1mm adjustment you make gives you something extra, but also takes something away. Trying and roughly copying an existing board would be a good bet, pity you are in QLD, you could try my Hardie Special, that Decrep built.

With the board Decrep made me, which is what you're talking about for yourself Gestalt, it's such a good all-rounder, I know if I wanted it to perform better in the waves, I would lose things like it's eraly palning performance which I really want. The only adjustment I've made about the bboard, is my mindset, when in the waves, I think of it as riding a 10ft Mal, instead of a slashy 6ft thruster.

hi guys,

the board is meant to be a lightwind wave board. for early planing i got a board that has been referred to as a dining table. so this one will be meant for the surf. I hope to use it from about 8 knots to 16 knots.

that said. like all compromises in life i would still like to keep the planing threshold low. so the area in front of the straps is relatively flat but the rocker is continuous and gets steeper as it moves back. (+5mm of rocker @ 465 either side of the apex then it kicks more)

the apex is 910mm in from the tail.

the three figures that are measured every 250mm from the tail are. 4, 13, 22.

but i may change that to 4, 14, 25 to give it a bit more kick.

hi Decrepit.

yeah, i was thinking i should move the apex forward a little.

1000 puts the apex just in front of the front straps. so i guess where i have it means that i have a fair amount of rocker going on. i will also measure my gear to see what was used. my wave board turns very well and i am happy with it so will start with it.

have you tried moving the apex forward and aft before?

if you want i could email you a pdf so things are a bit more obvious.

at the end of the day the guy who will shape the board has a vast amount of experience. he will definately tell me whether what is drawn will work or not.

but it is good to get ideas from others with lots of experience too. helps me understand the whole concept a little more.

thanks again for your help, it has been appreciated very much.

hi decrepit,

I have totally redesigned the rocker. i used parabolic curves and went for 2 rocker lines. (i guess obvious to those that know what they are doing understanding centreline and rail rocker but i only just figured it out..)

centre rocker has 22mm of lift from about the middle of the board to the back. this is relatively flat because of the lift versus length and should "hopefully" be fairly fast and efficient planing wise.

the rail rocker has 24mm of lift from the 910 distance from the tail. which because of the shorter rocker length provides a more curved outline and will "hopefully" provide better turning.

so both curves have different apex postions, the rail rocker apex being closer to the tail then the centre line rocker apex. this also effects the rocker forward of the middle point of the board and also means the centre line rocker is flatter forward of the mast and will "hopefully" help early planing. The rail rocker forward of the mast also has more curve and that is what creates the 6mm deep V.

the result is that there is 3mm of v at the tail into no v under the front traps and through to 6mm v just in front of the mast track. the nose then has extra kick to prevent nose dives.

i also changed the plan shape. used a parabolic curve again. reduced the max width to 690mm and increased the tail width to 440mm. to achieve the rocker outline the tail now needs to be a squashed pin to allow the v to work properly.

due to the new parabolic plan lines the nose got wider as well to 460 which "hopefully" will help the early planing as well.

i must admit, now i am thinking 3d and making very subtle adjustments in CAD, and based on the fact that i don't know what i am doing. this could be an expensive balls up....

Formula for a parabola:

y = (x)squared

You can then squish it and stretch it by using different scales for the x and y axes. It will then take quite a bit of experimentation to get the scale and orentation of the board correct to get any meaningful results.

I thought that a hanging chain assumes the shape of a parabola, but it turns out that it's not the case... it actually forms a catenary, which is similar but apparently different.

With regard to rocker lines, I'm not sure that a parabola has anything to do with what the rocker should look like, apart from being superficially similar... but it is a very harmonious shape and if you built a board with a parabolic rocker you could probably sit on it and meditate for hours on the symmetry of the universe.

Hey Gestalt,

Sorry if the parabola comment came off as a bit harsh, I didn't mean it that way

If you wanted to get really technical then you'd figure out which part of the rail was engaged when carving hard, and make that sort of a radiused curve, at the correct angle to correspond to the water surface vs board angle when carving, because the board describes a curve as it carves. I guess you'd then have to fudge it a bit to get a good planing surface when the board is flat, and put in the right amount of vee... Then you've got crossover from cars with regard to toe in and slip angle. Aw cripes here we go again, off at tangents.

In the end just make it look the best you can, the good old TLAR (That looks about right) method seems to work well for most things

hi nebbian. check out witchcraft boards. plus here are some other links.

http://www.witchcraft.nu/index2.html
www.surfline.com/mag/features/anatomy/anatomy_textonly.html
www.boards.co.uk/articles/index.asp?ID_A=244&article_type=16
www.sticktheory.com/index.php?title=Main_Page
www.windance.com/info_source/assistant/design_construction/Board_design_seminar.htm

well i'm 96kg and i was hoping the board would be 120lt.

your advice has been gold decrepit. you really got me looking in the right direction. i know the whole design thing is a throw of the dice without a few variations for testing but it feels good so i'll see what happens...i have sent another pdf to you.

cheers again.