[b] Area10 said
[/b]Stick a fin box in it, DJ. It will be the best money you ever spent. I put one in just ahead of the rudder so I can put the rudder back anytime I want. Works great.
My older 17 has had a fin box put in behind the rudder.
No expert, but that seems wrong centre of lateral resistance wise.
Box ahead of the rudder would put the fin more or less where the rudder was.
I have never paddled this board with a back fin fitted, only the rudder. I think it would be a big danger to put too much fin on a board that does not need it.
This board also has a forward fin box fitted, which I have tried 9", 6", and vestigial fins in, of which the tiny vestigial one was most successful, but better off with nothing. Any forward fin made the board way too responsive to the steering, and I ended up fighting the steering with the paddle.
Far from an expert paddler, but I would stick with the rudder the designers intended the board to have.
I would like to think Naish / SIC R & D departments are smarter than me.
I paddle a ruddered board nearly every day, and rarely use the steering, but it is there when needed.
With the tiller fitted, if the rudder is a bit the wrong way I just give it a kick in the direction it needs to go, and it holds there.
If you need to hold the bow up paddling cross chop / upwind, or turn upwind from downwind, or the other way around, or quickly turn between waves it is really good.
Maybe more skilled paddlers than me can do without, but I find it really helpful.
I also think it is interesting, these big boards have relatively tiny fins, maybe relying on long hard rails and good board design, rather than trying to fix a dodgy design with a big fin.
The 17'4" Bullet has what appears to be an almost identical rudder profile to the Naish, and a similar size.
Ignore the camera mount behind the rudder - separate project.
My newer maybe 2102 17' Naish has a Curtis rudder fitted - not sure if this was standard, but I purchased the board from Windgenuity (Naish Australia) without it having a previous owner, albeit 2 years after it was released, so it may have been tampered with.
It's still
a pretty small fin.
12'6" SIC Bullet has a fixed fin of visually similar profile to the rudders.
Brilliant board to paddle.
Not sure what any of this means, know nothing about fins.
But I would stick with what the original designer intended, or if fitting a fin rather than a rudder, go small / similar size to the original rudder.