"Mega" kite board rocker - "Mega" od zakrivljenosti kite daske

After I got my kite board of the vac table, was quite surprised to find just a tiny board rocker. The bamboo spring back is much more than 30%, and wasn't expected this.

So what to do now? I could glue a second bamboo layer on top of it to get a decent rocker. But, it won't be a light weight board any more.

So, made an experiment and used a carbon - kevlar fiber fabric on top of bamboo strip to see how that will work.
And, I got some rocker.

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Nakon sto sam skinuo dasku sa vakumskog stola, iznenadilo me da je zakrivljenost (rocker) daske skoro nestala. Naime, kod bambusa je ocito povrat elasticnosti znatno vise od 30%, sto nisam ocekivao.

Dakle, sto sada napraviti? Mogao bih zalijepiti jos jedan sloj bambusa da dobijem pristojnu zakrivljenost. No tada daska nece vise biti lagana, vec znatno teza.

Onda sam za probu zalijepio carbon kevlar fiber platno na gornju stranu bambusa da vidim kako to radi.
I, dobih zakrivljenost.

 
To cut a kevlar fiber fabric is a real pain. You'll ruin a decent scissors in a second and fiber will be everywhere. And because I like to complicate things I want my carbon kevlar fiber on top on my board but not from rail to rail.
Than, I was thinking why not to semi cure some epoxy and than cut it? Immediately after, vacuum bag it.

Worked as a charm!

1) First I need a template for applying epoxy on carbon kevlar fabric.
2) Than applying just enough epoxy around a template.
3) One hour after I cut kevlar  with an extremely sharp knife around a template.
4) Done. Carbon kevlar fabric is now ready for my "mega" rocker vacuum jig - 10 cm! Used 50g 5:1 epoxy.

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Rezati carbon kevlar fiber platno nije lako. Cak i pristojne skare ce biti neupotrebljive nakon par sekundi rezanja i tkanina ce se razici po svuda. I naravno, zato sto ja volim komplicirati stvari, zelim da moje platno bude na gornjoj povrsini daske ali ne od ruba do ruba.
Onda sam dosao na ideju zasto ne bih upotrijebio epoksi i nakon nekog vremena probao rezati platno? I odmah nakon toga na vakum stol.

Radi odlicno!

1) Prvo mi treba sablona da nanesem epoksi na carbon kevlar platno.
2) Nakon toga nanesem malo epoxija oko sablone.
3) Nakoj jednog sata sa vrlo ostrim nozem izrezem platno oko sablone.
4) Gotovo. Carbon platno je sada spremno za moj vakumski stol i "mega" zakrivljenost- 10cm! Koristio 50 grama 5:1 epoksi.


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And 10cm jig for the rocker is because I'm still expecting 50% and more spring back! And that might make just about a decent rocker of 4cm:) Will see tomorrow! Can't wait...

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Zakrivljenost od 10cm je radi toga sto ocekujem 50% povrat uslijed elasticnosti! Sto ce mozda ostvariti pristojnih 4cm rockera! Vidjeti cu sutra, jedva cekam...