Fiberglass layer - sloj fibreglasa

A few nights ago I've made my first fiberglass attempt. Well, sort of. The first few runs were with my test ply wood and I strongly encourage everyone to sort this out before you fiberglass your real project.

For example, on the test run I've a used 'some' peel fabric (bleeder) and a Dacron fabric (breather). This proved wrong since the bleeder was not the right one and a Dacron fabric glued to the wood through the peel fabric.

The result was a 'hairy' ply wood, and impossible to sand off. Imagine an 'hairy' kite board:)
Like, "my board is so old that it grew a beard":)

After first test attempt, I've made a trip 'around a corner' to the fiberglass shop and bought some real peel fabric and real breather. All together around $15 for 3 meters.


So here we go:

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Prije  nekoliko noci uradio sam prvi pravi fiberglas pokusaj. Recimo. Prije pravog pokusaja napravio sam par probnih na sperploci i svakako bih predlozio da uradite isto prije nego glasirate glavni projekt.

Na primjer, tehnika glasiranja kaze da morate koristiti dva materijala izmedju fiberglasa i vakumske vrece - bleeder i breather (hm, kako ovo prevesti?). Ja sam odlucio koristiti neki materijal za koji mislih da ce biti dobar. No nije. Umjesto da se materijal lagano odlijepi sa fiberglasa kad se ljepilo stvrdne, on se je potpuno zalijepio (Dacron) i sperploca je ostala 'dlakava'. Nemoguce za odstraniti.

Zamislite 'dlakavu' dasku:)

Ono, kao, moja je daska tako stara da je pustila bradu :)

Nakon ovog pokusaja otisao sam do obliznjeg ducana sa fibreglas materijalima (ima toga ovdje:) i kupio pravi bleeder/breather (oko $15 za 3m).

Onda krecemo:

Also, on the test run my vacuum bag was sealed well since it was just a small plastic sealing bag. My 'suction valve' was working perfectly since the bag was well sealed!

Now, on the real attempt the vac bag was *not* sealed properly resulting in two or more hours wasted precious epoxy working time! The reason why wasn't sealed was a sellotape around the bag sides! When I finally found the cause it was getting late and couldn't run my vacuum pump for much longer (not having a garage or a 'man' shed doesn't help with a man's projects).



I don't have any more photos of the process. Was too stressed out knowing that the epoxy workable time was disappearing and not knowing why can't apply vacuum.


Learned lessons:

Check for the leaks! And check again all around the edges of your vac bag! Or better, permanently seal the sides on vac bag. And start working early in the morning.


Next time, the result. And, almost a perfect one...

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Na probnom pokusaju moja vakumska vreca je bila potpuno zabrtvljena, jer sam koristio malu vrecicu sa vakumirati hranu. Time je i moj ventil dobro radio jer je vreca dobro bila zacepljena!

Kod pravog glasiranja vakumska vreca nije bila dobro zabrtvljena cime sam izgubio dva ili vise sati dragocjenog radnog epoxi vremena! Vreca nije bila dobro slijepljena selotejpom jer se isti u medjuvremenu odlijepio sa strane! Kada sam konacno pronasao gdje je odlijepljeno vec je bilo dosta kasno te nisam mogao imati upaljenu vakumsku pumpu dugo vremena (nemam garazu sto bas i ne pomaze kod muskih projekata:).

Tako da nemam vise slika jer sam bio previse iznerviran znajuci da je sve manje vremena za rad sa epoxijem.

Sto sam ovime naucio:

Provjeriti gdje vreca pusta! Nekoliko puta. Ili bolje, trajno zalijepiti vrecu sa strane. I svakako poceti rad rano ujutro!

Slijedeci puta gotova daska! I to skoro pa perfektna...

Vacuum bag - vreća za vakum

Nakon uspjesnog vakumiranja testne sperploce sa fiberglasom, doslo je vrijeme glasirati pravu dasku.
Postoje samo dvije vrste materijala - PVC ili poliuretanska plastika za vakumsku vrecu. Ja sam odabrao vinil, dakle PVC plastiku koju sam imao od prije. Vinil je 1mm debljine i dosta je tvrd, no biti ce dugotrajan!
Trebati ce vam dosta velika plastika. Ovaj vinil je oko 180 sa 120 cm. Preklopljen je po duzoj strani dakle dobio sam 180 sa 60 cm radnu povrsinu tj. vrecu.

Neko sam vrijeme razmisljao kako zalijepiti stranice vrece no previse komplicirati ne vrijedi. Jednostavno sam selotejpom zalijepio dvije strane, a obostranim selotejpom stranu kroz koju sam umetnuo gipsani otisak i dasku.

Prije nego sto vakumiramo potreban nam je neki ventil koji spajamo na vakumsku pumpu. Stari, nevaljni ventil od auto gume i jedan kupaonski ili kuhinjski priljepak za keramicke plocice je dovoljan. Ventil od auto gume sam skratio i izrezao nepotrebnu gumu do pola ventila i skroz do zeljeza.. Kuhinjski priljepak sam probusio te umetnuo dovoljno ljepila i ventil. Gotov ventil na lijevoj strani zgleda ovako:

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After successful test vacuuming  with a wood ply and fiberglass, it's a time to go with a final board. There are two different vacuum bags - PVC or polyurethane plastic bags. I would suggest grab a vinyl sheet from a balcony blinds supplier. I went with a 1mm thickness,  quite tick but strong and paid only $5! You will need a sheet at least 180x120 cm so you can fold it to get 180x60 cm of working vacuum bag.

Some sites suggest gluing with a plastic cement but it's too complicated. I just used a duct tape on two sides and a double sides tape on the entry side of my bag where I've put a plaster mold and my board in.

Before we go with a vacuum we need some kind of valve for connecting a vacuum pump. Old, used auto tires valve and one suction cap for bathroom or kitchen is more than enough. Tyre valve I've cut and removed half of rubber to get to the metal part and on the suction cap drilled a hole (actually cut the top of it - it's got a hole already). Than poured some PVC cement and a valve in a suction cap. Finished valve is on the left side:

Zatim sam probao vakumirati dasku da vidim kako ce se ponasati gipsani otisak, daska i pumpa. Nesto obicne spage na dasku da vakum moze povuci zrak i to je to. Pumpa se palila svakih 30tak sekundi da odrzi vakum na oko 28 in-Hg. Ako tako radi grijati ce se, dakle pazite na pregrijavanje! Sada je sve spremno za glasiranje! Primjetite vrlo vaznu stvar, dasku sam pobrusio grubim papirom po povrsinama koje ce biti lijepljene! Inace bi moglo doci do odljepljivanja slojeva.

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Than I've applied vacuum to see how the plaster mold, board and pump will work. Some cord on top of the board and around the plaster mold to get the air out and that's it. The pump started every 30 seconds or so to keep vacuum on 28 in-Hg. It *will* be a quite hot over 24hrs! Everything is ready now for the fiberglass! Notice important thing, around gluing areas ( ie. foot pads) I've used a medium sand paper, otherwise there might be some de-laminating after glassing.

Fiberglass & Epoxy #3, test run - testiranje ljepljenja

For a long time no news from me! It doesn't mean I wasn't working on my kite board, for example I've needed a quite some time to finally finish my vacuum pump before glassing my board!
The reason - vacuum advance device from an old carburetor wasn't working as expected. And to source another one in Perth is no mean feat.
Than, I've spent some time thinking how to glue the two layers of my board. The decision is to try first with a two peaces of exactly the same wood. Routed similar holes in it as well.
This is how it looks like:

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Dosta je vremena proslo od zadnjeg clanka! No, ne znaci da nista nisam radio po pitanju izrade daske za kajtanje, vec je trebalo vise vremena da zavrsim vakumsku pumpu prije lijepljenja daske!

Razlog kasnjenja je neispravni vakumski dio od starog automobila koji je dosta tesko nabaviti ovdje gdje zivim.

Nakon toga, dosta sam razmisljao kako da zalijepim dva slojeva daske. Odlucio sam napraviti probu od dva komada istog materijala u kojima sam izradio slicne otvore.

Evo kako izgleda:

I will be using the most common epoxy for fiberglass  105A & 206B. This is my third epoxy product since already got the epoxy for gluing and epoxy for sealing. The expense now just for this three products is around $130AUD but hoping this will last for 3-4 boards. That is, if I'll make that many:)

The fiberglass cloth is  4oz and thinking to use 2-3 layers between plywood layers only in the middle of the board and under the footpads as well. Two layers diagonally at 45 degrees and one straight. Not sure if will be glassing both finished sides of the final product. Probably only top side anyway.

All of this might try on a test run. Hopefully, will go well!

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Koristiti cu uobicajeni epoxi za fiberglass 105A i 206B. Ovo je treci epoxi proizvod koji sam kupio jer vec od prije imam epoxi samo za lijepljenje i epoxi za brtvljenje. Sve su to drugaciji proizvodi za drugu namjenu. Trosak za sva tri proizvoda je sada oko 130$Au, no nadam se da ce trajati za 3-4 daske. Ako ih toliko napravim:)

Fiberglass tkanina je 4oz tezine i razmisljam koristiti 2-3 sloja izmedju sperploce kroz sredinu daske i ispod vezova za istu. Dva sloja dijagonalno polozeni i jedan ravno. Nisam siguran da cu glasirati obje strane gotove daske. Najvjerovatnije samo jednu i to gornju stranu.
Sve to mogu isprobati na ovom uzorku. Drzim palceve!