Hi am thinking about starting my second surfboard, this time I want to use glass-on fins. If I am using home depot eps foam with 1/16" balsa skins is there any point to installing high density foam under the fins?
I will use 2.5 oz glass under the bottom skin and 4 oz glass on the bottom outside. Sometimes I grind my fins in the sand and I don't want them to come off but will a foam insert be overkill? Should just I use extra glass on the tail?
Thanks,
trent
Extra glass both sides of your skin in big wide patchs under the fins should be sufficient.
JD
With the 1lb home depot foam I’ve had de-laminations whenever I used glass on fins. The de-lam is between the balsa and the outer glass. I think boxes set into board with a stronger foam supporting the box holds up better. Kind of what speedneedle’s boards look like.
We’ve also found that with 1/16" balsa, a layer of glass under the skin helps. We’ve done 4oz under 4oz over for both sides, and 2 oz under with double 4 oz over on top and single 4oz over on the bottom. Makes a really solid skin.
Eventually the foam will break down in a large area surrounding the fins and the skin and inner glass will delaminate from the core.I would install high density inserts that attach to the deck skin,even if its just 2# eps.I stopped using the home depot foam due to the foam failing,dealing with vents,vent failures,high density inserts take too long,it shapes like crap,in the end weight savings and strenght are not much different but the build is labor intensive and costly compared too other methods.Where are you located trent?
I put 4 oz. single under the skin (bagged down) and the usual glass on layup on the outside. This board has seen significant use on well overhead days with no issues yet using 1 lb. foam.
Yet being how long,mine last just over a year and then they fall apart.It was a real bummer seeing my magic board placed on life support,only to be set aside because it was faster and easier to shape a new one using better materials and a more streamline build method.That is a sweet looking board Pompano,what brand of resin are you using?
jesus, the local brand of goo sold up the road from me. This is the fast RR. The quick kick is going on this board’s replacement, although I’m putting in future boxes for that one. I took a longboard fin full on T-bone collision to the rail and the fin rode the CF up the rail (not splitting it) but I ended up having to replace wood and it was wet, etc… This board was the bomb on the Thursday of the peak day swell from that one hurricane we had. I surfed RC’s up to double overhead on sets and so good. I was reading about some jealous west coast guys whining about East Coast surfers on some thread on here.
im with speedneedle. xtra glass both sides
Thenks for the replies, guys. Maybe I'd be better off trying to find a source for 2lb eps.
The deck of my first board seemed super durable for surfing but it only lasted a few hours after I decided to take it out with a kite and started jumping up and down on it. I was thiking of using a double balsa sandwich or balsa plus foam for the deck but maybe a 2lb core makes more sense if I am going to abuse the board.
Jesus, I live in Sarasota, FL, I have been up by St Augustine a couple of times to ride mantanzas inlet.
even if you use extra foam the fin will still delaminate glass from balsa. the balsa is the week link