Rethinking Quad

[OkiWild]

Our surf here in Okinawa Japan is so different day to day, that it's really hard to do a back to back comparison on fins, unless you're willing to drag out and change fins while in the water. Even then, with a 6' tide swing, the wave shape changes drastically within the space of an hour.

What I have settled on with SUP is how much I hate quads compared to thruster...but I have this one board...

Where the forward fins are so wide, that it likes to slide more than rail turn. It's sooooo annoying. Like when jamming a hard backside cut back it seems the board wants to stay flat instead of going way over on the rail, causing the fins to slip.

So I was thinking maybe it just needs more fin on the rail...aaaand back to a quad. For three days in similar conditions, I've surfed it with Futures F6 fronts and QD3.75 rears. While this makes the board a rocket, and goes top to bottom very well, foot steers insanely good, hard on that rail, and it still wants to slip.

Today looks to be more of the same conditions, so I'm swapping for the QD4.0 rear fins, which are still small, but substantially larger.

Pics are the fin comparison, front spread, rear spread.

Just a possible interesting exercise in futility.


Will report back 


 

[PonoBill]

I generally keep going smaller until the board starts to slide--I like the feeling. But yes, some of the futures quad setups are just so good it's hard to consider something else--like the controllers I had on my L41. I like the way thrusters pivot on the tail, but for rail-to-rail turns, it's hard to beat a quad.

Of course, it's been so long since I've surfed anything but foils that I probably couldn't make them do anything worthwhile. I'd probably start over with a single fin.

[sflinux]

Have fun experimenting.  I think it was the Surf Splendor podcast with Richard Schmidt where he shared how he likes quads, but has the large fin in the rear.  I have one board that has future boxes where the front and rear box depth is the same (requires spacers to use new futures quad rear fins).  I have a 7'6" quad egg that always felt squirrely with the normal quad setup with the big fins up front.  Then one day I tried a setup like Richard Schmidt with the front fin in the back, the board felt perfect.  This board has the futures front box for both front/rear.  Don't be afraid to go too big in the rear fin, if it feels too locked in, you can try reducing surface area for the front fin.
The other thing worth trying is a keel fin setup.  I have some boards that feel really good with this setup (and some boards that don't).

[OkiWild]

Head high, inside out, and pure glass on a reef a mile off shore. That small change in fin size completely changed how the board feels. Still slips if you really put the grunt to it, but it's 90% better. I'm in love with the board all over again. Now I have to decide if I want to try the Futures 4.15 rears, which are a little bigger yet, or...Futures sells the same three rear fin sizes (3.75, 4.0, 4.15), only in an 80/20 and flat. All of the rears I have are symmetrical, and Futures states the 80/20 and flat foils are better for fins on the rail, which this board is... At $70 for two fins, it's a bit ridiculous...


To start, I was using the GL2 quad in this board, and it just made the board too stiff. They're really big fins. Rocket, and would hold a rail, but didn't really want to transition, and just felt...stiff. I think that's what turned me off to the quad. Thruster was OK for turning, but felt slow, and didn't feel connected on a steep wall. There was just no happy medium, and I really cooled off to this board, and have been riding 9x27 and 10x28 long boards for the last year+   

This newest set up feels really good. Holds the wall on the steepest drops, acceleration and speed are there, and feels much better on a hard toe-side turn. I guess I'll burn the money, and go with the same size, only a flat foil first.

[sflinux]

Futures does have some new fins in their collection for rear quad (surface arear small to large):
Pivot Quad Rear Small: Area = 10.27 (new)
Neutral Quad Rear Small: Area = 10.73 (new)
QD2 3.75: Area = 10.73 
Pivot Quad Rear Medium: Area = 11.51 (new)
Neutral Quad Rear Medium: Area = 11.67 (new)
QD2 4.0: Area = 11.67 
GL2: Area = 12.19   
Pivot Quad Rear Large: Area = 12.41 (new)
Neutral Quad Rear Large: Area = 12.6 (new)
QD2 4.15: Area = 12.60

It sounds like you found the right size for most conditions.
I would suspect the QD2 4.15 may feel too big like the GL2.  The Pivot Quad Rear Large may be a safer option for going bigger.  The Controller Quad fin set has a pivot fin the back which I believe is in between the Medium and Large Pivot Quad Rear (Area =12.06).
Blane Chambers used Controller Quads for the rear pivot fin:
https://vimeo.com/user1612124