Im gunna start another board, might put some attention to detail this time and make it a little less ghetto.
Few questions, and a guessing game.
1:Does anyone use thinners in the epoxy to make everything wet out easier? If so, what sort?
2: In this video, a yellow mix goes on first, than a blue mix.. I was guessing epoxy with pigments?
Is this thickened epoxy with pigments? If so thickened with what?... or is it some type of gelcoat maybe?
I have used Klegecell (?) from FGI up in Brookvale. I think it was about $100 for a sheet, that was about 2mx1.2m.
It is similar to divinycell and I think it was 80 (kg/m3?)
As for inserts, order them from Stuart Bell Sails (in Perth), as they seem to be the cheapest I have found.
For thinning, have a look at the Westsystem.com website. They have a description somewhere of what works.
Yeah, it looks like they have mixed up some pigment in their epoxy. I was looking at using this instead of paint for some repairs. I bought some from Fibreglass Material Services in Mortdale/Peakhurst. They have a small amount of colours there, although it isn't really obvious where they keep them.
Never ever use thinners in epoxy. The only product that uses a thinner is one called Everdure, but thats for sealing timber. Epoxies are solvent free and must say that way to achieve their full cure. Use a good quality epoxy too.
Products like FGI r180 are goopy and not that nice to work with.It's only formulated as timber sheathing resin and the ES300 is only a little better.
"Atl composites" (R246 and H160 medium harderner or H126 fast)resins are much nicer to work and have superior properties. Sp/Gurit also do a good range.
Go for the Kinetix R246TX resin with the medium hardener from ATL- no need to thin out the resin as it wets out 6oz carbon beautifully (as keef says adding thinners to the rein weakens it). Plenty of working time at 25 deg C to get your layup right and get it in the bag. If your aim is to make a easy sanding filler coat add Q Cells or West System 410 Microlight Blend to the epoxy until the desired consitency is obtained.
I have used methylated spirits to thin out epoxy succesfully for the non skid.
1 No I don't use thinners, Boards laminated on warmer days can be lighter as the resin is thinner, a heater in the room will help the resin be thinner. I laminate all my layers on plastic and then take the wet glass off the plastic and the excess resin stays on the plastic for 1 layer of 4 oz on the inside of the board I use 160ml of resin for one side on the outside bottom side with 2 layers of 4 oz I use about 350ml resin.
2 I guess the same as you I reckon the first coat is thinner o get into any pin holes and the second layer is just a thicker filler coat. For a filler coat for one side of a board I use 200ml resin and 300ml of qcell after I have squeegeed this on the board I warm it up with a heat gun (but be very very carefull !!!!!!!)air bubbles then come out of the resin reducing pin holes in the laminate.
Instead of painting the board you can add pigment 3% to the laminating resin and also add pigment to the filler coat resin and qcell, you may have to do a second coat. You can do swirl pattens in the laminating resin by mixing a base colour then pouring other pigmented resin into the base colour then laminate the glass with this and use a clear resin as a sanding filler coat, this method also saves on the weight of painting. It works better with polyester resin as colours don't bleed as much into each other as with epoxy.
3 It's spot putty available from most car shops use for filling up pin holes. If painting a board I usually Sand the filler coat, apply the primer(which shows up pin holes) then spot putty the pin holes.
4 Divinycell, corecell anything from 75kg/m3 to 100kg/m3.
I the vid he uses a similar amount of carbon to what I use, that amount of carbon uses about 200ml of resin. Good luck
plenty of great advice, cheers guys!
thats a NO for thinners then! I didnt find the Fgi resin to bad, but goey would describe it well.. I also had it pretty cold because I was worried about it goin off and always laid up at 1am for some reason!!.. this might explain why if felt thick.. I will try the Kinetix R246TX and laying up at midday.
I am probs going to go with the pigments in the layup/filler resin rather than paint.. I found some White resin pigment at a local boat shed, Its like a really thick paint and smells "painty".. Is this the right stuff for radical action??
I have fgi Q-cell which should do the trick for the filler coat like last time, good to know thats a standard approach... the car body filler would be quicker but I guess it would look pretty silly without a coat of paint over the top..
keef thats the second time if heard about "ringing out the fibreglass" to loose excess resin.. I dunno if I would be brave enough to try it, ive been wetting out the resin on plastic like the Nelson videos and ive had no problems with weight.. but its an interesting idea. Ill have a look at the 3oz satin weave.. I have airlight cloth 130g.. would this be similar? I have no idea what an oz is
Its good to hear some ratios of resin, to start with I was mixing a ration 60:40 resin to fibre because I read it somewhere.. but gave that up quickly as I was wasting so much excess resin..
The HD foam I was talking about was the foam block insert that goes in the mast track?, Im VERY familiar with 3mm HD kleegercell foam, definitely the most cumbersome S#$t invented.. I doubt he is using kleegercell in the video as that stuff looks little more flexable..
edit: this is the foam, anyone know what it is and where to get some?
think you might have got that ratio wrong way around... usually with carbon composites you can get up to 60%+ fiber volume fraction... 60:40 fiber to resin. So yeah cause I think the fabric is a bit less dense, if you use half the weight of resin to weight of fabric, you should be fairly close.
3 oz fabric is roughly equiv to 100 gsm.
how many fins you putting in this new board? I reckon you should do 5, way of the future 
As I mentioned earlier it will be divinycell or corecell about 80kg It comes in a 1.2m x 2.4m sheet that's 30mm thick, a boat builder will have some offcuts or you can laminate a whole lot of thinner sheets together using resin thickened with qcell weighed down with a few bricks until the resin dries.
The pigment needs to be compatible with epoxy resin otherwise you will get a weak laminate, google epoxy pigment Ive got mine from "fibreglass and resin sales" and "kirkside" over here in Perth.
Yeh agreed for sure. I think I also made a bit of a mistake when I had a wild stab at the density of resin too, plus my dodgy 11pm back of envelope maths is horrible. Think you should be closer by using similar weight in resin to carbon, then adding a little till its wetted out properly.
Maybe I should build a board, refresh my memory so I remember all this junk!
yeah my rato mix was definitely the wrong way round, It didnt seem right but I found it on this otherwise good writeup, maybe this is why this guys board was so heavy, apparently this ratio was taken from the fgi data sheet!.. either way, I was using nowhere near this ratio on my last freestyle..http://www.lbwindsurfing.com/raceboard/design-construction-longboard-windsurfer/
I realise that Q-cell + epoxy is a poormans filler.. but would it still make sense using it because I want to mix it with a pigment? probably white or a light colour..
yeah swoosh Im only putting 4 fins in.. 4 of these badboys ready for corros
I have used the 8mm Klegecell for supporting footstrap and masttrack inserts, and also for finboxes. I based this on the boardlady's technique, although I think the thickness was slightly different.
The interesting thing about this, is that when I have cut out the finboxes or footstrap inserts on some boards, there has been no high density foam reinforcement. I can visualise the people in the Cobra factory routing out a hole and pushing an insert into the foam with just a single layer of glass, and no supporting hd foam.
Given that I have been replacing these footstrap inserts because there are leaks, I wonder if the hd foam will make the replacements last much longer.
One of my favorite things to do to boards I have been renovating is to put in dual hole footstrap inserts so that I can use two screws in each end of the footstrap instead of one. I hate twisted footstraps, and this has solved this problem once and for all. It limits the variety of footstrap hole positions, but as I design these for my feet, it doesn't matter too much.
I have cut out us-boxes to replace with tuttle or powerbox and it is amazing that some of them have no reinforcement. The better ones seem to have a 3mm layer of hd foam, but I would expect better.
qcell is fine. the west systems ultra light weight filler IS lighter but also slightly more expensive. I'm still working my way through a 2kg box of qcell bought 10 years ago :)
Most epoxies aren't UV stable. They will turn yellow. If you pigment it you won't notice it as much. Atl composites do a UV stable system. From memory It's R105 and H125. A board finished just in filler will look ugly pretty quick as it will mark just by rubbing an unwashed hand over it.
