Can a board make noise ?!?

General Discussion
1

Hi swaylockers, I need a little help here.

I shaped a few 9’8 Nose Riders this year and all the surfers have been delighted surfing them.

But a few days ago I was in the water with one of them, and he said to me that the board would make some kind of noise on the bottom turns.

Never heard of that before … Have you ?

Here are a few specifics to help :

9’8 square tail, 3 stringers,

23"1/2 wide (I don’t recall nose and tail)

glass on fin, 10" keel (home made with volan)

(btw I checked the fin of course, and it’s perfect, nothing wrong with the angle nor the lamination …)

2

jep a board can make noise!

most of times i think its from the fins. i know from windsurfing, if you go realy fast or if your fin is a little destroyed on leading edge, the fin began to “sing”.

the noise you mean comes from turbulents at the fin.

sorry for my bad english.

merry christmas and some nice days

klaus

3

of course it can make noises…

a litlle warp on the edge of someting will make a sound when is in movement.

Imagine also a middle fin not well thigt… it will begin to vibrate e produces noise…

Imagine also when a board breaks… you will ear only one noise … ahaha… I did…

4
Quote:
Imagine also when a board breaks.... you will ear only one noise ... ahaha.. I did...
Quote:
when a board breaks

Ive heard that - A sound difficult to forget!

5

(btw I checked the fin of course, and it’s perfect, nothing wrong with the angle nor the lamination …)

You may think it’s perfect?

Let a good fin foiler (Pro) check it out and I bet that he could refoil the fin and take the noise away?

It’s most likely the fin. Check the thickness foil.

Don’t deceive yourself!

6

from another point of vue… it could be water in the ears…ehehehe…

7

Why does a fin hum? usually it’s because it doesn’t know the lyrics.

Or: Leading edge too sharp. Trailing edge too dull.

I once had a fin that hit a perfect Bb on a bottom turn.

I once had a fin that hummed so bad (back in '65) I could feel a cavitation on a stall or a cutback. It turned out the board had a twist. I had ordered the board (from a well known South Bay maker) with “very very thin rails”. They made the whole board “very very thin” and it twisted in short order.

8

Glass on fin, yes!

Trailing edge has a bead of resin on it

you need to sand the trailing edge (sides)

lay a straight edge on it and you will see an air gap

I did the same thing, ooops

9

Sounds like!

No pun intended.

10

Or, wear ear plugs. Kidding… Mike

11

Thanks a lot for your input.

I know what to do for know : experiment my home made glass on fin on my own boards !

12
Quote:

Glass on fin, yes!

Trailing edge has a bead of resin on it

Yup. That’s the cause most of the time.

13

Only time I hear anything from my boards is when I fall. Things like “oh!shit” and “this is going to hurt”.

Never mind, that is me saying that not the board.

14

Most noise comes from the trailing edge. I was once told that if there is a flat spot on the trailing edge that is wider then 1/32 of an inch it will hum. If you take a razor blade and scrap down both sides of the trailing edges in the thick areas you will save yourself a lot of sanding time.

15
Quote:

Leading edge too sharp. Trailing edge too dull.

You nailed it BalsaBill

Fluid mechanics explanation:

The noise comes from something vibrating at a high frequency. the board itself will not resonate at high frequencies, but a fin will. If the leading edge is too sharp, you can get little vortices, or eddie currents, that flow off the leading edge. The same applies for a trailing edge that is NOT sharp. A bead of resin could also have the same effect. At certain speeds or angles of attack, or combination of the two, the vortices that come off the fin make the fin vibrate at its resonant frequency and thus it gets loud enough to hear.

My 10 cents as resinhead would say.

16

I love the hearing “noises” when I surf!

Probably because it’s so RARE! haha

The beautiful “hissssssssssss” of a long, fast, swooping bottom turn…MMMMMMMMM!

The definitive “smack” from off the lip…AHHHHHHHHH!

The pronounced “thump” of a perfect landing from a good elevator drop…OHHHHHHHHHH!

(excuse me…I think I have to go change)

Then of course there are the bad noises… Oh!..Ummmmm… that of course I NEVER hear.

There’s the “CLONK” of the board hitting you on the head after you’ve been dragged over the falls. UHHH…So I’ve heard.

The “CLACK” of your forehead coming down in the center or you board after it got sucked out from under you, then the wave drives you head first into it.

I…I mean…that’s what I’ve been told anyway.

The “Tump clump clack thonk” of your brand new, custom Mike Barron shaped board getting mangled by some kook on a POS pop out rental.

(I’m not bitter about it at all.)

17

The only noise I like is from the wave…

18

Maybe it’s the creaking of that log before it snaps?

19

hope not ! triple stringer 9’8 glassed with 2xvolan on deck and 1 volan on bottom, plus 2 hotcoats, plus 3" thickness : it has to be solid.

if it snaps I’ll loose a few customers :slight_smile: