Hi there
My new Narlu 10'6" GTW hums or sings as I take the drop. It also does it when planing with a windsurf rig? I thought it might be a vibrating fin so I tightened them, but it still hums?
Interested in what it could be because my JP 9'8" Fusion never made that noise?
Thanks
I like that sound. The board is happy 
and I am going fast. I assume it is the fins resonating. A couple of my boards do it, including my Naish Hokua.
Select to expand quoteAdfreetv said..
Hi there
My new Narlu 10'6" GTW hums or sings as I take the drop. It also does it when planing with a windsurf rig? I thought it might be a vibrating fin so I tightened them, but it still hums?
Interested in what it could be because my JP 9'8" Fusion never made that noise?
Thanks
it's the flux capacitor, all new Naish boards have them
when you hit 88mph...HANG ON TIGHT!
It is the fin trailing edge.
The solution is in www.seabreeze.com.au/forums/Stand-Up-Paddle/Review/Fin-Whistle/
It is the fin trailing edge. (like colas said)
Give the trailing edge a light sand of file to square it off..
This will not only get rid of the hum but also make the fin safer..
Haaa.....sometimes sanding doesn't work.
i have a hand shaped McCoy Nugget and it hummed after sanding......pain in the ass!
Wow I did not expect to such terrific responses. Thanks all.
The Colas post with the diagrams overloaded my brain but also fascinating.
So I should sand it off square and that won't slow the board down at all? Or would moving the centre in forward or back resolve it without sanding?
Select to expand quoteSlab said...
Haaa.....sometimes sanding doesn't work.
i have a hand shaped McCoy Nugget and it hummed after sanding......pain in the ass!
Just wondering.. What type of fin are we talking about with the McCoy Nugget. 
Select to expand quoteAdfreetv said..
Wow I did not expect to such terrific responses. Thanks all.
The Colas post with the diagrams overloaded my brain but also fascinating.
So I should sand it off square and that won't slow the board down at all? Or would moving the centre in forward or back resolve it without sanding?
Yep you sure get good responses here.
Sanding is the first option as above. If that doesn't work. Moving the centre fin is the next move.
I would suggest slightly forward of its current position.
Hood luck and let us know how you get on.
ET. 
I use to have this problem when I fibreglassed my fins back in on my surfboards ...just a little bit out of line and it hums.
you might have a crock fin ..it was usually the side ones ..that made the hum.
maybe change them and see if the nose disappear s ..be worth a try. 
Select to expand quoteDavidJohn said..Slab said...
Haaa.....sometimes sanding doesn't work.
i have a hand shaped McCoy Nugget and it hummed after sanding......pain in the ass!
Just wondering.. What type of fin are we talking about with the McCoy Nugget.
Big thrusters.....glassed on as usual. I don't surf the board anymore.....but is a keeper for the wall when the Mrs doesnt freak out
Select to expand quoteDavidJohn said..Slab said...
Haaa.....sometimes sanding doesn't work.
i have a hand shaped McCoy Nugget and it hummed after sanding......pain in the ass!
Just wondering.. What type of fin are we talking about with the McCoy Nugget.
Big thrusters.....glassed on as usual. I don't surf the board anymore.....but is a keeper for the wall when the Mrs doesnt freak out
Select to expand quoteTardy said..
I use to have this problem when I fibreglassed my fins back in on my surfboards ...just a little bit out of line and it hums.
you might have a crock fin ..it was usually the side ones ..that made the hum.
maybe change them and see if the nose disappear s ..be worth a try.
Yep, if sanding doesn't work, the fin box may have been installed not exactly straight, or even tilted to one side, or both,,,,, yikes!
If that's the case no fin will work, you'd need a new box.
But hea, that's just the worse case scenario, sanding will work, it will work, it will work.
Select to expand quoteAdfreetv said..
So I should sand it off square and that won't slow the board down at all? Or would moving the centre in forward or back resolve it without sanding?
No, not square off! that is the worst for humming. (Case 1 on the drawing I posted)
Sand the trailing edge only on one side, but keep a blunt edge for safety.
i had a spooky point thruster with glassed in fins which hummed when you were really hooking. I loved it.
Select to expand quotecolas said..Adfreetv said..
So I should sand it off square and that won't slow the board down at all? Or would moving the centre in forward or back resolve it without sanding?
No, not square off! that is the worst for humming. (Case 1 on the drawing I posted)
Sand the trailing edge only on one side, but keep a blunt edge for safety.
Interesting colas (case 1 drawing) because it was a company that designs and makes fins that originally told me that squaring off the trailing edge is the fix for this problem and I've done this a number of times in the past and it's fixed the problem.. Not made it worse.. Maybe there's something more going on.. I used to wonder if it's a faster flow of water on one side that the other and if so maybe the science says sand the trailing edge on one side only is the scientific fix to even things up.. but I will continue to square it off because it has works for me in the past.. and never not worked.
It could also be something as simple as a damaged leading edge. Clean up any imperfections or damage to the leading edge before you worry about the trailing edge shape.
Thanks but the fins are new and have no damage (yet).
I think I will move the centre fin forward to see if that helps. Shall I go all the way forward. It can only make it easier to turn.
Fin trailing edge, I have an old atlas woods that did the same back in the day, sand the edge slightly, humming will go away.
I had the 2015 Nalu 10'6" GT and my fins hummed also. I moved the centre fin backwards and forwards in the finbox and the fins still hummed.
Just do what I did. Ignore the noise for now. Keep using the board. The deck will get nice and soft under your feet. The board will break in half like mine did. Then you won't get to use it anymore. The annoying fin noise is now gone. Easy fix.
Aaron
that Sucks. I broke my JP in half with my hip. That is why I bought the Nalu. I hope that it doesn't break too. Yikes
