What’s that noise?

[Homer J]

Coming down my mast is a sort of whirring grinding noise a bit like the sound of one of those Australian music things that they whirl round their heads on a rope if you know what I mean. When I put my ear to the compression post it confirms it’s definitely from my mast.

My thoughts on what it could be so far are

1) the bearings on the wind anometer wearing out - but it still shows accurately, is running smoothly and is held away from the mast on a thin bracket and just doesn’t seem big enough to generate the noise
2) wind is running over the mast sail slot (in mast furling) like blowing over a bottle
3) it‘s blowing Through the rigging and somehow resonating

none of these seem terribly plausible to me. Any ideas? Anyone had it before. I’ve had the boat 5 years and don’t rem hearing it before although it is possible.

 

[chrishscorp]

Coming down my mast is a sort of whirring grinding noise a bit like the sound of one of those Australian music things that they whirl round their heads on a rope if you know what I mean. When I put my ear to the compression post it confirms it’s definitely from my mast.

My thoughts on what it could be so far are

1) the bearings on the wind anometer wearing out - but it still shows accurately, is running smoothly and is held away from the mast on a thin bracket and just doesn’t seem big enough to generate the noise
2) wind is running over the mast sail slot (in mast furling) like blowing over a bottle
3) it‘s blowing Through the rigging and somehow resonating

none of these seem terribly plausible to me. Any ideas? Anyone had it before. I’ve had the boat 5 years and don’t rem hearing it before although it is possible.

Its called a bullroarer

Sorry cant help with the noise, it could be some annoying harmonic set up on the rigging I would try and eliminate that cause first.

 

[RupertW]

Could it be your topping lift? If you loosen off the topping lift and support the boom does it still happen?

 

[Blueboatman]

?
Wang down hard on the main sheet or vang , see if that does it.
Not a wind generator deceiving you as to the source , per chance ?
Slacken all the halyards temporarily incl furled headsail .
And lastly
See if noise persists when wind direction shifts relative to rig and sail slot

 

[prv]

Wang down hard on the main sheet or vang , see if that does it.

On my boat that's normally what causes it. Slacking the mainsheet slightly (still tight, but not bar-taut) shuts it up.

Pete

 

[sarabande]

It's called vortex shedding. If it's the mast, and not the rigging, the way round it is to wrap a line round the mast to disrupt the air flow over the slot. If on running rigging, altering the tension will deal with VS, as noted above. If standing rigging, then even a light line and a few winds will normally stop it.

 

[Homer J]

?
Wang down hard on the main sheet or vang , see if that does it.
Not a wind generator deceiving you as to the source , per chance ?
Slacken all the halyards temporarily incl furled headsail .
And lastly
See if noise persists when wind direction shifts relative to rig and sail slot

I’ll give your suggestions a try. It’s not a wind generator. I don’t have one and it’s definitely my mast

 

[Homer J]

On my boat that's normally what causes it. Slacking the mainsheet slightly (still tight, but not bar-taut) shuts it up.

Pete

Actually I did have the vang and main sheet under tension. Thanks for your suggestion.

 

[Homer J]

It's called vortex shedding. If it's the mast, and not the rigging, the way round it is to wrap a line round the mast to disrupt the air flow over the slot. If on running rigging, altering the tension will deal with VS, as noted above. If standing rigging, then even a light line and a few winds will normally stop it.

Vortex shedding - I’ll remember that - sounds impressive. I can see how your theory would work, similar to roof bars on a car. I’ll try this if the main sheet / vang doesn’t work.

 

[Homer J]

Could it be your topping lift? If you loosen off the topping lift and support the boom does it still happen?

thanks For the suggestion but unlikely as not under tension. The vang holds the boom up.

 

[Leighb]

Our last boat was a Halmatic 30 with in mast reefing. The wide slot behaved like an organ pipe when we were moored with the wind on the quarter. Forward of the beam and dead astern were OK. In strong winds it howled like a banshee, it was always a factor in choosing which way round we moored in marinas, but shifting winds could catch us out. Worst episode was a 3 day Gale tucked up in North Fambridge, we tried all sorts of things to quieten it, winding spare halyards around the mast, hauling our thickest warp up on the topping lift to try and block the slot, etc. Nothing made much difference. Our friends on the cruise seemed oddly reluctant to cruise with us again!

 

[Bilgediver]

. Nothing made much difference. Our friends on the cruise seemed oddly reluctant to cruise with us again!

Get a few boats into the marina with in mast reefing and you soon have endless complaints from the nearby houses.

 

[Elemental]

Could it be your topping lift? If you loosen off the topping lift and support the boom does it still happen?

That's what causes it on Seaspray...

 

[michael_w]

On my old boat the adjustable whisker pole would make a noise like someone playing a french horn, badly.

 

[Refueler]

The Match 35 I delivered from Germany to Latvia - when sailing - that keel stepped mast sang like a trumpet on heat !! When really 'singing' it was really annoying and I slept out in cockpit !

 

[Homer J]

Hmmmmm, a remarkable lack of comfort from these replies! Seeems another disadvantage of in mast reefing. All things considered probably won’t go for in mast on the next boat.

 

[sarabande]

If the boat is in a marina, to reduce/eliminate vortex shedding, you can wind a line diagonally round the mast the stop the air column vibrating. An alternative is a length of bolt rope run up the slot on a spi halyard. Anything to disrupt the column of air and the mast slot that create the vortices.