Fin placement for fish

He guys, got a question for you. Started making a fish (6’2" ,N 16 3/4",M 21 1/2",T 16"), and as I have only ever made modern tri fin versions of this design I was wondering about placement for twin keel type fins. How far up do the fins go (from tips of 5 1/2" deep swallow). My normal numbers for this don’t look right when drawn on the blank. Also thinking of adding extra fcs plugs to change into a quad, (would your little charger fins be better Herb?). Appreciate any input into this, thanks.

A lot depends on how long the fin base is. A good rule of thumb I use with great sucess is to set the FRONT of the fins at 15 " plus or minus, depending on rocker and template curve(or lack of it) from the tail. Everybody keeps forgetting that how the rail line ahead of the fins enters the water is actually more important than the fin placement in relation to the end of the tail. aloha, tw

I did a board very similar to yours (the pic is in the archive)with 7" base keel fins placed at 10 1/8" from the tips, inset 1" and toed 3/8" @ 7". The board rides terrific. Hope this helps.

A Frye Fish sold recently on e-bay for $778.22. There are several nice pictures of the board on the auction page. It looks as if the foil is symmetrical(?) - also hard to say for sure what the fin settings are. I have from a reliable source the set up on another Frye Fish that is a little shorter. Fin dimensions: 9 1/4" x 4 3/4" Set at: 6 3/4" from tail, 6" from stringer, no toe, no cant. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3615112526&category=22710&rd=1

The tail on board was 16 1/2" so 6" from stringer wouldn’t be quite the same as for yours. If you wanted the same sort of set up, you’d probably be better about 5 3/4" from stringer to account for slightly narrower (1/2") tail width. Also - Clyde Beatty (Rocket Fish) sometimes puts FCS plugs way back near the tips of the swallow tail and has tiny trailer fins (like Herb’s superchargers) back there. I’ve seen guys rip on those at Rincon.