oke first of all my english isnt perfect, so i hope that everyone can understand what i am trying to ask
I have made my own board out of EPS200 foam (5’11 retro Fish) but now its time to place the fins. I have bought the FCS FK-2 fins to go with this board.
I have already drilled the holes in my board and everything. The last thing i have left to do is pour the epoxy in the holes to keep the plugs in my board
BUT i heard that you need to add a “filler” to the epoxy to make it thicker (???)
so here are my questions:
is it true that you need to add something to the epoxy when placing the FCS finplugs? If so, why cant you use epoxy only?
What kind of filler do i need then? i have a friend that has Aerosil powder. It would be great if this stuff is good for my problem. He said i could use that if i wanted to make the epoxy a bit thicker, but i dont know if this stuff is right for placing the plugs.
Do i have to take extra messures before i pour in the epoxy? Because i have read here on SwayLocks that the epoxy near the fins can become very hot and cause damage to the board :S
i hope you guys can help me out here. I tried the Search option but i could not find a direct answer to my questions!
oh and for the ones that care…here is a picture of my board:
I set my fcs plugs with 5-minute epoxy glue - but then, mine went into wood not foam! Hopefully someone with more experience will come along and address your questions. Meanwhile - that is a nice looking board, dude! Years ago I rode a 5'11" fish, before they were "retro" LOL. Little wider than yours, with a flat round "potato chip" nose. Man I loved that board!
FCS has a new system (Fusion) that works much better than the plugs in EPS. Fusion was designed for installing in the lam, so it's a little late for that now. The H-pattern of the plug install can exotherm to the point of melting the EPS, not good. There's lot's of info on here about ways to avoid/minimize the exotherm: doing a 2 or 3 stage pour, using ice bags to cool deckside, etc. Use Fusion for your next board.
Aerosil will work as filler, just don't use too much
The aerosil powder will work. Guys use everything for Q-cell to ground glass with white pigment. If your part "B" Epoxy is "slow"; you should be fine. Although warm temps will speed things up. The faster the hotter. As stated above you can flip the board after the install and lay a ziploc baggie of ice cubes on the deckside of the plugs .
The FK-2 is 7" long with only 2 tabs. You need to do a really good job of installing these plugs otherwise you will have them rip out. I think you need to insert some high density foam then glass patches over it then install the plugs. But then again it would be as easy to use the fusion boxes and patch over the top and hotcoat providing you have access to the boxes and jigs or can make the jigs. If you go with the normal plugs and no high density inserts then a good install complete with the H pattern to the deck is a must as well as a good undercut to the underside of the bottom to get the resin stuck there too. I cant see the point of filler for Epoxy resin unless it is to bulk it out and lessen the heat build up. The Aerosil is weaker than the resin. Apparently the more usual additive of milled fibre makes the Epoxy weaker too so why bother? Mix enough resin to do a plug. Pour in enough to bond to the deck and partially fill the hole. Use a stick etc to make sure the resin soaks onto the underside of the deck and will stick to it. Make sure you don’t put too much resin in as I like to let this set a little and lose some of its heat before adding a bit more then siteing the plug then leave to set a bit then top up round the plug to the surface. In between the pours put the mixed resin in the freezer. You will be surprised how many times you can cool/freeze it and bring it back to life. Fiddly doing multiple pours but it is so not nice having the volcano exotherm. Also consider putting in an extra plug in case you want to try the keels with 3 tabs later.
The Aerosil is weaker than the resin. Apparently the more usual additive of milled fibre makes the Epoxy weaker too so why bother? Mix enough resin to do a plug.
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Good advice overall. However, that's the first time I've heard of milled fibers weakening the resin it was used to reinforce. To me, it's more like using aggregates in cement to make concrete (much stronger than cement on its own). I would think q-cel or maybe even Aerosil would weaken it as it expands the resin as opposed to soaking it up like milled fibers.
Back to the question at hand, I'd recommend doing the 2 or 3 stage pour as suggested by others and the additional reinforcement that Marks recommends.
Id like to hear more about the milled glass / epoxy weak link and the details on why it truely is weaker as compared to a straight mix of epoxy.
When I was shaping 100% epoxy boards, I would do my plugs in stages as some have already suggested to keep the risk of exotherm to a minimum. The goal is to keep the pour very clean on each stage so that you dont coat everything and so that the other stages have area that can adhere to properly. Synringes come in very handy for this job.
As for the install, the proper hole shape and geometry is much more important than whether or not you use a scoop of filler or not. Personally, I use only a pea sized pinch of white pigment, but I have used filler in the past and have never had a plug fail, because I use the correct bits and technique when drilling the holes.
To insure an install that won’t melt the foam, do two pours… one without the plug in the hole, to the top of the foam pillar (if you don’t have the pillar, you’re already in trouble), and smearing some around the inside of the hole above the pillar. The second pour is done with the plugs in the holes, and you just pour around the plug until it’s beading up around the plug. No ice needed. I’ve never used ice. I have used cold wet cloths, but the two pour method does not require any cooling measures, even with fast hardener.
Yesterday it was DOH here in New Jersey. I saw two broken boards before noon. A third board was a quad that had the fin plugs pulled right out… and the guy lost his fin. I picked it up and looked at it, and noticed the holes did not go through to the deck. I said, “…they F#%!ed up the install, that’s why you lost your plugs.” The guy looked at me and said, “Actually, I did it.”
Good advice nj_surfer. its important to do the install right. Surfboardmedic i had a look to see if I could find the thread but haven’t been able too yet. Perhaps it would have been better to say that the milled fibre doesn’t add any strength rather than makes it weaker. I did come across a Probox thread where Larry says the milled fibre adds no structural strength at all. Different context but perhaps relevant. Maybe it reduces shrinkage in PU installs? Here is that thread link http://www2.swaylocks.com/node/1029266
First of all. I cant tell you guys how much i appreciate all your honest answers and opinions! i had no idea everyone would be so helpfull! thanks a lot!
2nd: thanks for the compliments on the board! its my first one and i am very proud of it!
3rd: if i do a summary of all the advices i get this:
— try to cool the board (with ice packs for example) so the heat can clear its way. great idea! i will do this.
— make sure you drilled the holes correctly with a pillar. i did this and i have about 1,5/2 mm space between the foam and the plug. good?
— use very little Aerosil OR dont use it at all (due to bubble and loss of strength). ****
before i make my final decision about this, I want to make sure that am i correct with these points! i dont want to ruin my board at the last minute i think you guys will understand.
if the first 2 points are good, then the only think that i have to ponder about is the use of Aerosil (and IF i am going to use it: the amount of it!) if you could help me out with these final things. i would be gracefull!
In poly, you need a filler to make the glue less brittle. Epoxy is more flexible, so the fill is just there to make it easier to work with, stays in place where it comes level with bottom surface.. Has to still be thin enough to run down H-pattern, that's why I advised not to use too much.The fill (and a little pigment) also color the the ''ring'' around the plug for a cleaner look.
that is a very good idea too, thanks Lee_jordan. I will see if i have enough epoxy left to try some stuff out. ofcourse i wont use my plugs for these tests… that would be a waste.
And about the tufflite look… i think it is a bit of an illusion on this picture, since it is actually turning a bit yellow-ish because of the epoxy i used I guess my next board will be polyester
thanks for everything guys! i have done some extra research and i will do the following:
i will mix the epoxy with very little Aerosil.
since it's winter, i will operate in the snow in the garden to clear the heat from the drying epoxy (laying the board in the snow would have the same effect as icepacks :P)
i will pour in 2 stages (also to reduce the heat production)
reading this, do you guys have any other suggestions or things i really need to pay attention to? or do you think this will do perfectly? or do you think, pouring in the snow will reduce the heat enough to pour everything at once?
I would advise keeping the board and resin at 60 d F or over, and bringing the snow inside to apply to the curing install. Temps too low will stop the reaction of the epoxy completely.
are you dutch, and in scheveningen? i can help you
if not: plenty of advice already on here
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my take:
your board looks so good, you want the install to look very good too, so color your resin white
my bad experiences with powders result in tiny little airbubbles once flat sanded, not good, use plain resin first try!
do the h pattern to the deck [ i use a hollow yellow electrical pipe, roughened up on the end]
do a semi pour with white colored resin [you can buy that color in any hobby or sailing store, though the latter are expensive]
once you have poured the first halve, make sure it is not higher than the bottom of your boxes. meaning: if you have done your first pour, you should be able to hang your fins with plugs in, without touching the first pour
I guess my next board will be polyester