Hi,
I am new to posting, having read many threads on swaylocks and have made a few boards this year, all learnt from the internet. I am on my 4th now; 1st one (stringered PU) machine cut, shaped the rest by hand and from now on, now I’ve got the shaping bug! I have used extruded styrofoam “floormate 300” on my 2nd, 3rd and now 4th. I can’t source eps very cheaply in the UK, but I have had success with xps so far, even taking one of them to Soup Bowl, Barbados (summer), no blowing and still in one piece. They feel solid enough, I have only used s glass on the xps, but it is expensive and I am now looking at getting my costs down to less than £100, the last board costing £180 in materials, although I think my skill at laminating is on a massive learning curve still, because of the ammount of resin I have gone through compared to what I have read that is acceptible 50:50, resin to glass. My layup so far is, 4+4 s cloth bottom, 4+4 + patch s cloth top, 2" laps top and bottom. Resin, I have used RR qwik kick on my first hand shape and RR 2000 on my second, I will be using RR 2000 from now on as I’ve heard it offers more flex and I prefer working slower, as I am still a noobie.
I’ve heard stories of xps shearing easy and causing delamination, because of it’s small and therefore weak cell structure, so I’ve been careful to prime the board well. The last one I ran some tests on how 5 razor blades arranged in parralel inbetween 5mm slips of wood and protruding by 2mm could improve the “grip” on the foam, across the whole of the board apart from the rails, it worked very well, working best running perpendicular (across the width of the board) to the shear direction (across the length of the board), chunks of foam came away in this orientation as opposed to lengthways scoring, which was an improvement on no scoring, but because the orientation was the same as the shear force the resin against the glass gave way before the foam. I realise that scoring across the surfboard could weaken the board and promote buckling and snapping, so my last board I arranged the scoring at both 45 degrees to the length, to have the best of both worlds.
I am thinking on my 4th board I am going to use a 300g (9oz) biaxial cloth on the bottom and top, plus a 4oz s cloth on top after the biaxial, plenty of lap on each layer, so I will have 22oz on the rail. I want to try a different technique on laminating to get down to 50:50 resin to glass, to keep costs and weight to a minimum. I’ve heard about resin first then roll out the cloth on top to soak the resin up and then when the resin is setting pour a resin hot fill. Can anyone tell me how hot is a hot fill? I guess this is to make the resin spread very thin and soak into the glass thoroughly. How is this best applied, with a squeegee or brush? Any other tips on laminating this way and with 9oz biaxial would be much appreciated?
Thanks for any advice!