Just finished laminating an eps foam/epoxy fish, 5'11" and am now ready to glass on the fins. I have searched the archives under fish fin placement and there is all sorts oadvice but I am still not quite sure on placement as this is my first fish. Hoping to get some specific advice on what would work best on this board. The board is thick (3") and wide and has a 12.5" wide tail at the points. The buttcrack is 3.5" deep. The fins I have are TrueAmes glass-on Keel fins I got from Foamez, they have a 7 1/8" base with about 1.5" of sweep of the tip. From what I have read I dont want this thing to track so I dont want to put them parallel with the imaginary stringer (stringerless). I am assuming I will line the fin tips up with the end of the buttcrack. The board has 3.5" in the nose and 1.5" in the tail for rocker with a very slight V in the last 18" of the tail. What sort of cant should I go with on the fins and how close to the rail? Do I need any cant with the slight V in the tail? Any advice would be greatly appreciated!
have a look in the archives first. lots there. good luck.
ulu,
I line up the keels with the top of the buttcrack(traiing edge) and the tips. Usually around 6.5 inches up and 1 1/4 off the rail. Double foils straight up, no toe in. Single foils 2-4 degree cant and 1/8 inch toe in. Your buttcrack is really shallow for a fish in my opinion. I would not put the rear edges at 3.5 inches. I would put them about 6inches up and lined up with the tips. See what happens. If it tracks too much grind them off and re-mount them. Or, with a crack like that you could put a couple of twin fins on there and a small midline trailer. Of course, won't be a 'real' fish anymore. Tons of advice on keels in the archives like Greg mentioned. Mike
Yeah, I was suprised when I measured the buttcrack it was only 3 5/8" deep, Maybe I sanded a bit off it during the shaping but it looks pretty normal. When I held the fin on the board lined up with the crack it looked way to far back so the 6" sounds more like the right placement like you said. They are single foil fins, will review some more of the archives, like you said, I can always grind them off and re-set them if its not right. Heres a poor photo of the unsanded tail.
Just two hrs. ago I was scoping out one of these 
It’s got Futures Rasta/Sea Shepherd keels set at 7 ‘’ from the tail tip , trailing edges 1 3/8 to 1 1/2 ‘’ from the rail ( couldn’t tell exactly ) , toe’d 1/4 ‘’ - I 'd estimate the cant to be 4 deg., maybe even a little more.
Those Rasta keels have a fair bit of rake , of course - more than yours from what you say. Any way a bit of info for ya.