Looking for support on how to fix a slow board, if possible.
The details are in the plan shape and I put the fins at 8.5" from the back, 1/8" toe, 4 deg cant, 1.5" from the edge. Note the rails are downish style and probably a bit too pinched. Bottom contours are a basic single to double to vee.
I’ve ridden a few times with a few different sets of twin fins and it goes okay on mid size waves but always feels slow once you lose momentum on smaller waves. Just feels like it doesn’t want to go. It does paddle and glide in waves really well. I’ve only made 6 boards so far but every other board with more rocker has performaned much better.
My question is, can the lack of speed generation be due to the fin placement? I understand it may just be a bad rocker (or foil, shape, rails, etc.) but I’m wondering whether adjustment of the fin placement can fix the issue. Still deciding if I should try it as moving the boxes to a standard thruster setup, push up the twin (plus trailer) placement to around 9.5 -10" up or even try out a quad setup.
Has anyone made a bit of a runt of a board then turned it around with a new fin setup or placement? Or is a slow board always going to be a slow board…
Also open to constructive critism on the board in general.
How many different sets of fins have you tried? I have had boards completely transformed by simply changing fins. I have a Sharpeye Disco Cheater that I wasn’t happy with until about the fourth different set of fins I tried.
so much going on here…what is the length of the board. are you trying to do a twin, 3fin widow maker set up, single? what’s the plan? You see when we build a board we usually have an idea in place what will be the best set up. Nowadays guys think they can toggle between a single fin, to a trifin, to a twinfin…but this is not good. A jack of all trade, master of none is not a good set up. 8.5 from back sounds like a twinfin? or a really wonky back fins for a quad?
Sometimes the problem IS the rocker and IMHO there is only a marginal benefit to be gained by other modifications. What you describe- the board having less rocker and good glide is puzzling.
Plan shape looks like it could be twin fin fish, if the tail was cut out. I don’t know how the square tail would impact fin placement, but I would think standard fish fin placement would be a good starting point.
I know there is a twin fin that is made to set further back, like the trailing edge is behind the end of the box, I can’t recall the name or who makes them, but with a little searching you might find them.
Could be where your back foot is, or it could be the rails. I like tucked under rails with a hard edge. The rounded off rails don’t feel as fast. I also noticed that I need to stand over the fins or way back to get some boards to wake up. I never liked stomp pads, but I’ve been adding them to some of my boards to make sure I keep my foot as far back as I can.
This is my opinion, i am no pro surfer, neither pro shaper. Its based on my experience with my surfboards.
I think the low rocker, flater concave should mean Faster board in general.
I’ ve had a standard shortboard that wasn’t thick enough on the tail to set boxes at 12 inches so i pushed them to 14 inches (measure for shaper dot at back of box) and the board was really fast.
I respected the space for the rear fin and moved it acordingly.
I also set the toe-in so that the tip of the fin would still fal on the Edge line.
I have a 5’10" single fin with a 12" inch box for fin and when i move the fin forward ( even further then the back foot) it gets fast (unresponsive but fast)
One other thing, have you considered the cant angle of your actual fin setup. More cant could mean loser, Faster?
Off the numbers on your file. it looks like you could be feeling a touch to much tail rocker if your surfing average waves. Fin placement is pretty ballpark depending on what fins your using. I’d try something that would get the rear of your fins close to 7 1/4 from the tail. Something hybridy with a slightly longer base. Can’t could be closer to 6.5 degrees also on a hybrid style fin. Based off your bottom contour description I’m guessing your going for a newer style performancy fish. I like a 1/6 more toe also.
Don’t go thruster if you think your board already feels slow. Quad would work with what you have going on and would atleast get your more drive off the overall fin area when pumping to generate more speed on your own if your board and wave isn’t giving it to you.
