My new kiteboard, lightwind machine!

General Discussion
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First, a small background on me… I’m 17, started surfing when I was 6. I’m unlucky though, I live in St. Pete florida… aka:no waves here. So recently after selling our boat, (used to wakeboard) I got into kiteboarding… kiteboards cost about 600 dollars! And there’s nowhere to get one cheaper from a custom shaper. So I took it into my hands to shape me a board. Almost forgot to mention I used to shape clark blanks and glass them when I was 14.

I got around to getting the materials, and I got enough materials to make me at least 2-3 boards… unfortunantly they cut the divinycell up instead of giving me it in the 4’x8’ sheet… sucks, so I had to make a short fat board for lightwinds, not bad but meh. My layup was like bertburgers from november. Went through all the stages, got to laminating it, and I used 6oz carbon fiber. What a B@$ch that was to wrap my rails. So after glassing the top and bottom with carbon fiber I had to cut out strips to use for the rails. So it looks kinda dirty, plus the fact that I didn’t REALLY finish it… wind picked up once I got the gloss coat on the bottom, so I rough sanded the top, didn’t even sand the bottom for the little bubbles in my gloss coat. Drilled in my straps and put down my footpads and headed out for a nice lightwind session on my 12meter kite… should’ve used my 17, but it’s a big board (surface area) I’ve had one problem this whole time, what I used for my inserts my screws keep stripping out of it. It’s a nylon board that’s called starboard. I drill in my screws that hold a little peg in place then you use a little spacer and a nut to hold down the straps… I’ve ripped out one whole side of one, and one screw on the other, so I plan on cavasiling them back in.

But, here are some design flaws I’ve found with berts design for surfboards and how it’s not a good crossover to a kiteboard…

Too stiff, it could just be the carbon fiber so I’m going to use only one layer next time, and it’ll be the bottom, the top will be just regular glass. After that, we’ll see.

Divinycell rails aren’t needed, I have a medium thickness board, so the next one, instead of Dcell rails, I’m going to mix up some epoxy mush with fiberglass powder and use that for the rails, just to make them a lot thinner, and these one’s shall be sharper.

This isn’t part of berts plan, but instead of using starboard I’m going to try and find some different/better inserts that won’t strip out or I’ll just cavasil the screws in in the first place.

My next board won’t be so wide (this one was 123cmx42cm) and it’ll have fins (homemade I don’t know yet.)

Also the next board I’ll put more time into the shape and finishing, this board was to test bert’s sandwhich coring process of Dcell-EPS-Dcell with Dcell rails… the next one I’ve already got my revisions and I already know what to do… so more time will be spent on shape.

Does anyone have any suggesions?

especially on inserts? I’m thinking of using helicoils and I don’t know what else…

2

are you 17 ?

man , that technology you’re using lost me !!

thank goodness for swaylocks eh ?

17yos can use divinycell , carbon fibre , epoxy …

good stuff !!]

ben

[now at the risk of sounding like an old wanker …"when I was a teenager , …

no , really !

…if I had walked into a surfboard shop , and asked for those materials you mentioned …they would have looked at me as though I was from another planet , let alone not known what I was talking about . I’m sure they would have thrown me out the front door … and told me not to even THINK of making my own boards . [mind you , one grumpy old boardmaker here in perth who shall remain nameless , said the same thing to me… five years ago !]

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p.s. - Justy , I nearly forgot to ask …I’d LOVE to see photos of your creation …do you have some you could “post” here , please ?

cheers !

ben
4

I’ll post some in a few minutes, but let me warn you… it aint pretty… like I said the carbon fiber had a hard time warpping the rails so I sloppily added some strips on the rails… plus I didn’t even sand the thing… I was WAY too stoked to ride!

One of the straps is pulled out too… and it’s still sandy from sunday… secretly went out without the girlfriend knowing so had no time to clean it or the kites :slight_smile:

pics in one second…

5

why did you use carbon?

stoked for you but next time you can user cheaper materials and get better results…cf is hell expensive and hard to work with…that dcell eps approach is a good one

6

Forgot to mention, it barely weighs 4lbs.

Gotta fix a few things though, as you can see from the pics. You can see the cavasil on the bottom (it’s the white stuff) It was used for the rails, once again. And you can see that I didn’t really sand out the top… but this was an experimental board… the next one will be a very good one… when that’s finished I’ll post once again.

http://img.photobucket.com/albums/v319/Optionryder420/Pictures069.jpg

http://img.photobucket.com/albums/v319/Optionryder420/Pictures070.jpg

http://img.photobucket.com/albums/v319/Optionryder420/Pictures071.jpg

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Quote:

why did you use carbon?

stoked for you but next time you can user cheaper materials and get better results…cf is hell expensive and hard to work with…that dcell eps approach is a good one

I used carbon because coming down from 20+ feet in the air, you’d kinda need it… but only on one side.

8

Carbon is a waste of money and your time. NO manufacture bothers to use it anymore, except for heel patches and that M-6 stranded fake stuff.

Next board, you’re better off making it from 9/16 ply, double layer cloth, bend the rocker in…but that weighs closer to 7 lbs.

Use styro blanks, regular glassing, vacuum bagging, so you can run single concave bottom. Footstrap inserts can be lexan rectangles placed in the blank before glassing. #12 stainless sheet metal screws.

Fins from RainbowDistributing from your neck of the woods is about $16 each. Plugs is double drill resin, so won’t cost anything, hardware from a marine supply store.

Stiff boards are bascially worthless, just break.

Softy boards last forever, and aren’t that soft since your feet are 12" from nose and tail, keeping flex to a minimum.

Narrowness and rocker keeps the board together for landing big jumps, plus some rider technique to NOT land dead flat.

9

Stiff boards aren’t worthless, it’s the best board I’ve ridden for lightwind.

I’m sticking with what I’m trying, I’m doing something different, learning something… but thanks for the idea with lexan, I was just looking at some of that stuff actually.

10

Good for you, personal experimenting is the stuff of innovation!

Someone always has to be pushing the edge of the design envelope.

But I’d consider visiting a kiteboard store and feeling and bending a few of 'em.

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Yeah, I know how they’re supposed to feel, but trust me, stiffness is the way to go for lightwind… because you’re not going to be doing highpowered jumps in lightwind, period.

My next board I want as flexible as an underground board… so very flexible, and with this one I learned carbon fiber isn’t the way to go… I’m either just using glass on the next one, or just the bottom will be carbon fiber… especially since it’s harder to wrap the rails with carbon fiber.

12

try having a few strands of CF running down the bottom and just use regular glass for the rest of the board

13

hi,

you didn’t say how thick your board is.

how many layers of 6oz cloth?

just assuming 1/8" D-cell top and bottom and 1/2" core. That’s pretty thick for a 120cm kiteboard.

1/2"-9/16" total thickness is a pretty good target value.

that means 1/4" EPS core? By the time you get it all glued up, i wonder if it will be weigh any

less than a single sheet of 1/2" D-cell.

taper the sides and tips for some more flex.

about 12-18oz of cloth, top and bottom, with some extra for heel patches.

most folks agree that the carbon is overkill.

i know you diisagree, but you’re the one that said it was “too stiff”.

carbon isn’t necessarily stronger than glass, it’s just lighter and stiffer.

and if you dont use good bagging techniques, it’s just more expensive.

besides, even flexy boards are stiff in light wind.

regarding inserts:

stainless T-nuts from the hardware store.

Insert the T-nut from the back side of your top skin or from the bottom of the board before glassing.

if you want to compare notes and see what others are doing:

http://groups.yahoo.com/group/boardbuilding/

have fun,

-bill

14

It’s a little less then 3/4 inches thick. And it’s a LOT lighter then other manufactured boards.

I never said using carbon fiber wasn’t overkill, but I am trying the next board with just one layer of carbon fiber on the bottom and eglass on the top.

I only used one layer of carbon fiber on the bottom and top.

I’ve been subscribed to that yahoo group for a long time… I like to figure things out for my own though.

I’m still going to try what I said earlier… same layup minus the Dcell rails, and use Epoxy mush instead. Along with one layer of 6oz carbon fiber on the bottom, and one layer of 4oz eglass on the top, doubling up where the footpads go.

I’m thinking about making my own fins… I was going to go buy some clay and make a mold for a fin, then just make a bunch with the extra carbon fiber Don’t know what to do on how to attach the fins though… time will tell.

I’ll keep swaylocks updated on what I find out and what works best with what… this’ll be an interesting trip.

I’m open for suggestions, so don’t think I disagree with anyone. I listen to everyone, but I’m still going to try out my own thing… not like I’m selling these boards, it’s just a TON cheaper to make your own then it is to buy a 700 dollar POPOUT!

15

Fin, look at kiteboard/wakeboard fins…

Sheet of 1/4" ply, better the grade, the smoother and finer.

Cut them out with bandsaw.

Attach them to board with 1/4x20 screws, thru the board. Drill matching holes on fin and tail of board. On the board, drill it bigger, then fill it, then drill with proper size bit.

That’s how all the fins are attached…and big fender washers.

16

:slight_smile:

your’re gonna be just fine.

but as long as you want to figure things out for yourself…

you’re in good shape to do alot less guessing on the next one.

since changes will be minimal, you can measure the flex of the first board

and predict stress and flex for the next boards layup.

at this point the comparisons will be pretty simple.

just remember, stiffness and strength are not the same.

removing too much reinforcement on the top, compressive side of the board

will just make it snap. the top needs to be just as strong as the bottom

(actually it needs to be stronger)

-bill

17

Damn… well, I’m still going to try it out, maybe a strip or two of carbon fiber down the top? I don’t really want carbon fiber on the top because the 6oz is really thick and doesn’t wrap the tight rails very well… So I’m going with the eglass.

It’s going to be 2 weeks before I start the next one, parents are leaving and I quit my job… so I have enough money to eat for the next two weeks. After that, I should have a new job, keyword should, and I’ll buy some more epoxy, since that’s all I need right now.

18

ive never kiteboarded before but im thinking to glass some straps into my 6`5" poopee.

and have a bash at it .

i always thought it would be cool to try riding a surfboard with at least a front strap

any one tried this '( besides tow in)

Just here … resin by itself isnt all that strong or flexible … Its the cloth that makes it strong…the epoxy mush idea sounds messy and not that strong…i think your better off sticking to a foam or balsa rail… try laming a few pieces of balsa with 4 oz cloth for the rails once you got three layers with glass in between its incredibly stiff.(this is how im doing my balsa fins and there very stiff)

Berts techniques could be applied to basicaly any composite type board/watercraft …Just substitute materials …

For example a snowboard mite have a balsa core glass top etc etc…

Did you use a vacuum bag to make your board?

from what i understand.from reading peoples posts and own experience

the deck needs to be the stiffest …just use a thiker skin and heavier glass schedual…

Good luck

19

I’m trying to cut back weight, so that wouldn’t be good… Forgot to mention that the epoxy mush isn’t just epoxy, it’ll have fiberglass dust in it. I’m trying to reduce weight without reducing strength and trying to give it flex, without reducing strength. I’m going to stick with what I have, try it out, if it doesn’t work, then it’s back to the drawing board.

I think what I have should do the trick, if anything, I’ll take the carbon fiber out all together or just put one layer in between the Dcell and the EPS, but I don’t think that would even help much. Maybe one layer of 4oz on the top of Eglass and then where your feet are another layer.

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Your at a geat forum for surfboard building, but kiteboard building, this is not really the place. For some excllent information on kiteboard building go to the yahoo group “boardbuilding”. They specialize in kiteboard building.

http://groups.yahoo.com/group/boardbuilding/ Like Swaylocks there is a vast amount of information to work with.

Anthony