To you epoxy guys and fin gurus...

To you epoxy guys and fin gurus,

Theoretical: If you have two modern trifin shortboards, same shape but one is a real light epoxy and the other is a heavier PU, how would you differ the fin set up? How do you approach setting up these ultralight epoxy boards?

Real World: I have a 6’9" light epoxy hybrid/shortboard trifin and I have noticed the lightweight benefits but also the lack of projecton problems people have been observing. I was hoping this could be partly addressed by altering the fins (G5-FCS). Bigger? Smaller? Stiffer? Rakier? And altering my surfing but that is my problem.

Thanks, SF

Request: Please, lets not go into light vs heavy, PU vs epoxy, popout vs custom debates. I’d like to focus on fins. Thanks.

You might want to try jsut using bigger fins for more drive, have you tried the fcs occy fins??

Most often lack of projection is the board shape fault (too curvy or too rocker’d)…or it could be too much toein. A 6’9 is a big board and the G5’s are very little in comparison…how much do you weigh? Bigger fins like the Rusty’s will give you more drive and perhaps more projection as well. G5 foil shape is poor and pretty thin (too flexy - more drive loss). I use mostly 6’4 EPS, wide thruster with Rusty fronts and G3k rear. A 6’9 is also a bit slower to pump/drive due to added swingweight.

Too many variables. Among them

  1. fin fore-aft position, toe-in, and cant

  2. fin stiffness

  3. board rocker

  4. board bottom contour

Any of these out of sync with the others will reduce drive.

hey surffish,

first thing that comes to mind is shape …

if you have two identical shapes of different constructions , they will go different …

a heavier board needs more focus on features to give control , conventional boards have evolved over time to a point where those features have become a stock standard style of curve and you will see it on 99% of shapes …

a light board gets control back from the reduced weight , so now you can afford to include features to give it more speed and squirt …

but right now your problem is projection …

you have 2 fin choices or direction …

1 is set your tail fin slightly further back or increase its size slightly , that will stiffen the feel but also give a more drawn , drivy feel , more of a carvy feeling …that one will make tight pocket turns a bit more difficult …

the other option is go for a rakier template with more tip area … that will also keep it driving for longer out the end of the turn , because the side fins are also contributing to adding drive and there wont be as much focus on the tail fin doing all the work , this option would not inhibit the pocket hooks as much as the first option , but still have an effect on stiffening it up up in the pocket as well …

ok im off for some coastal exploration …



When I bought my 7’0" and 7’4" Parmenter Stubb-Vectors I was told that Dave suggested using only the Rusty’s with their big tip for these hybrid designs…He was right as I haven’t found anything better in FCS plastic (occy’s, GPR, AMs, Sunny’s etc) for his vectors.

Which means… Go Carbonlite

AM’s, Redline’s and especially the Simon Anderson’s will give you a ton more drive than any of the poly FCS’s. The AMs are looser and the Simons are spooky… Makes you think you’ll pop a plug… I use them exclusively with my 7’0" Randy French and 6’8" Merrick Flyer Surftechs.

So as you can tell I’m a carbon convert for FCS setups.

If you’re game… The TC Redlines/AMs with the new 3D Redtip center is a kick butt combo…

If you’re need a set of plastic Rusty’s let me know via PM as I may have a spare set lying around some where as I’m slowly converting to Futures and Redex… Sorry no extra Carbonlites to give away…

Next time you get a board done go Redex or Lockbox instead so you can move your fins forward and back a bit to get more flexibility like what everyone is suggesting here. Back and further apart to stiffen and forward and closer to loosen. These new box designs are much more flexible than the old fixed FCS plugs…

yeah I concur with the last two postings…Ive been using lokbox in the center exclusively now for optimization…thought about doing it all around but I find adjusting fronts is very sensitive and tricky…plus I got my boards very nailed down after a few years of trial and error…so center adjust only and usually no more than 1/4 inch or so…beyond that and some of the magic is lost…

Ok, if everything else is the same, could it be that due to the epoxy being lighter/corkier you have less rail/board surface in the water/wave with the same amount of force from your legs and thus you need to change either: 1) rail thickness 2) outline 3) fins to make it ride the same?

Just thinking…



Thanks for the great input.

Bert/Oneula, your explanation and suggestions were very helpful. After reading them, I checked out the FCS line. These templates seem to match your suggestion of smaller back with more raked sides the best;


  • Sunnys: Big, raked but front and back are equal sized

  • GAM: Big, raked, back smaller than sides but thin tipped

  • GPRX: Big, back smaller than sides but not too raked


  • GR: Big, raked, but equal sized.

  • Occy: Big, raked but equal sized

  • GPR: Big, back smaller than sides but not too raked

Any suggestions? I’d rather not have to buy 6 sets of these for trial and error if I can eliminate some through your experiences.

Also, you mentioned that lightness gets control back compared to a heavier board. That seems counter-intuitive to me. Can you explain that more?

Oneula, you like the carbon. Do you feel that the lighter/stiffer boards match up better with the lighter/stiffer carbon fins?



My $.02 I used the GPRX model on my 6’10" round pin through most of last year on the noth shore here in HI. they worked great in headhigh to 2x and smooth condi. But, the carbon is strong/stiff they pull/crack FCS plugs like butter, but your epoxy is much stronger than the norm. 6’9" isn’t that big but you can go BIG if need be. Lets see who catches the wave first! sometimes you need to get in early and pump baby pump and then the weight factor comes in, Downhill racer around the big section another little pump or two off the bottom and up up and away, last year was epic and this is comming along fine. Anyway good luck on your decision, carbon is always on the top of my list, second by glassed on true Ames foam filled glass(super light/firm). G.