Looking forward to Area10's contribution to this...

JZOrewa said..
Does anyone ever tried using a big big fin for downwinding instead of taking a wider board? I mean, a really big fin, double the area and longer than a normal racing fin. It would've been home made or an adapted windsurfing fin maybe.
I know the main con would be more drag and probably difficulty in steering the board, but could it compensate the extra drag of a wider board?
Cheers

Think they call it a foil

DavidJohn said..
Besides feeling very draggie at slow speeds once you drop into a big runner at full planing speed the board will tend to rail-up due to the lift generated by the size of the fin. (depending on the shape)

While not as experienced as DJ even if I paddle yellow too :-) there is a point where a bigger fin stop bringing more hold and keeping teh board "flat" and where it does what DJ said. You just have to try and test based on your board, your style of DW and your conditions the fin that has the right size and shape - small enough to allow you to carve and angle while keeping the board nice and flat, and big enough to prevent having the tail so loose that you cannot keep control on a bump, also in marginal conditions giving you enough push to catch a bump. My bigger DW fin is under 40 sqi and my smaller is 28 sqi for my Naish boards (Maliko X26 and Javelin LE26). Dugouts are another story altogether.

I'm with DJ , i've tried the bigger fin theory for improved balance and found it didn't make much if any difference at all . i just use the FCS plastic 9" dolphin click in which cost around $50 and find that works just fine

DavidJohn said..
I've tried it and really big fins don't work very well for DW in my opinion.

Besides feeling very draggie at slow speeds once you drop into a big runner at full planing speed the board will tend to rail-up due to the lift generated by the size of the fin. (depending on the shape)

I've tried many fins for DW and I don't think you can beat an 8 or 9" dolphin shaped fin. Fins are a personal thing and there's many variations of the dolphin fin.

Thank's for sharing the information!
That was just a logical thought as usually fin's sizes are correlated with stability, the bigger the more stable, but I reckon there is a limit.
Cheers

JZOrewa said..

Scotty Mac said..
Try the VMG 44. Definently adds some suitability to a narrow downwind board. I used it on a ace 23 often.

I use a NSP Race 24, same length but looks like the VMG has more area. I know some guys that use VMG, they look nice! I ride a Carolina 22.5, but at 86kg and 6'4" I'm struggling with side chop and going downwind.

I would have thought they're pretty narrow boards for your stats - maybe a 25" board would be a reasonable compromise

DJ is right. i've Tried some massive fins - JL used to do a 13" Great White fin, and one of the first DW-specific fins created for SUP was 18" long! That was fun, coming into the beach...

Too much fin, especially too broad a base, makes the board round up and broach. Too narrow a base and too little an area in general, and you get too little drive, especially in smaller conditions. As with everything, it's a question of balancing the various factors of you, your board, and the conditions.

Don't try to correct stability issues with a fin. Get a board that suits you and the conditions instead, even if that board is not what the self-appointed heroes of SUP tell you is best. Everyone is different. I, for instance, prefer very low volume boards (like the Hypr Nalu Hawaii 12-6 and 14ft gun) for downwinding because in the conditions I paddle, voluminous dug-outs are a nightmare. A low volume board is much more stable and less affected by cross-winds and chop, and so you don't need to try to rely on a big fin to control it.

But other people like other things. It's very personal.

I mostly use an FCS fat boy for DW when winds are over 25 knots.

colas said..
Gong tried some prototypes 12 years ago...
www.gong-galaxy.com/magazine/news/remember-crazy-proto-racing-gong/


At the time they even thought of making it a production model available "in the next days"...
But as you can guess, the drawbacks (drag and sensitivity to water movements) proved bigger than the advantages.

That's cool! They say the board is just 52 cm wide but has the same stability as a 75 cm. For sure the fins play a very important role in stability. Thanks for the link Colas!