Chine Slap noise ST42

[Nomad Willy]

As Ski mentioned in post #2 anchoring from the stern should put an end to it. The chines are most often submerged at that end of the boat. May even have a positive effect on "sailing". However the wind over the stern may fill your boat w BBQ smells.

Another thing to seriously consider w the surgery of the chine option is resale value. The modified boat would most likely be a very wet boat even w wind and seas from abeam. I definitely would not buy such a boat but there are others that would consider it a plus .... at least until they ran the boat some. However spray coming aboard in a lot of instances may be generated by the chines. Without the chine break water may not be broken up into spray fine enough for the wind to bring it aboard.

My Willard is a dry boat and has no cup shaped chine. But probably the main reason she runs quite to very dry is that Willards go so slow. And that's no doubt has a lot to do w why she has no cup shaped chines. I've been intending to try anchoring from the stern and still intend to do it mostly to see if sailing is less of a problem that way. Willy's rounded stern may cause slap noises but I doubt it.

In sympathy w those that are bothered by the noise I'm sure glad we are moored where there are no sailboats as the haylard banging on aluminum masts was a noise I never found acceptable. The windmills (generators) I've not found acceptable either. So the "just get used to it" solution may not apply to many. Come to think of it there are lots of noises I find very irritating. Football games turned way up in the marina, boom boxes in cars ect ect. I had a friend in college in the 70's that said the next troublesome form of pollution was going to be "noise pollution". Lot of truth in that.

 

[Gdavid]

This is really just thinking out loud, but with enough ballast you could submerge more area of the chines and reduce the noise. For a boat your size, it would take an incredible amount of weight but it is a possibility. Perhaps a soft tank on the bow plumbed to a salt water wash down. I've sailed and cruised a lot of J boats and the racier models can be very loud aft at anchor due to the light stern which presents a large surface area just above the actual water line, with enough coolers, sails and gear shifted aft, you can submerge it and quite things down dramatically.

 

[Tom.B]

This is really just thinking out loud, but with enough ballast you could submerge more area of the chines and reduce the noise. For a boat your size, it would take an incredible amount of weight but it is a possibility. Perhaps a soft tank on the bow plumbed to a salt water wash down. I've sailed and cruised a lot of J boats and the racier models can be very loud aft at anchor due to the light stern which presents a large surface area just above the actual water line, with enough coolers, sails and gear shifted aft, you can submerge it and quite things down dramatically.

Unfortunately, it isn't JUST the water on the chines making noise. Water hitting the flat sides and the water that gets trapped under the bow rise makes a lot of noise too. I just don't think there is a viable solution. You just kinda gotta live wit-it.

 

[READY2GO]

For those of you that say you will get used to it, well maybe not. Not all boats are the same. We have a Wellcraft 2900 Express and a SeaRay 380 Aft Cabin. Both have chine slap but the noise is totally different. The Wellcraft sounds like there are at least five kids with ball peen hammers on the outside of the hull while the SeaRay has a much softer although still annoying slap. I could probably get used to the SeaRay, but there is no way in hell I could get used to the Wellcraft. Just saying each boat an each person has their own personality.

 

[Art]

For those of you that say you will get used to it, well maybe not. Not all boats are the same. We have a Wellcraft 2900 Express and a SeaRay 380 Aft Cabin. Both have chine slap but the noise is totally different. The Wellcraft sounds like there are at least five kids with ball peen hammers on the outside of the hull while the SeaRay has a much softer although still annoying slap. I could probably get used to the SeaRay, but there is no way in hell I could get used to the Wellcraft. Just saying each boat an each person has their own personality.

I've said it before and will say it again... Chine slap is one thing... trying to sleep in lapstrake [clinker] wood hull construction boat is a whole different ball game of too much noise. Man, that sounds like a kid with stick going past a picket fence... super annoying!!!

 

[AusCan]

You do get used to "an old slapper". And loud noises at night.

That's true. I've spent many nights on rig sites with all kinds of racket. You just get used to it, especially if the noise is constant or repetitive. If the noise is intermittent, like a slapping halyard, I find it much more bothersome.

I normally look at my neighbouring sailboats before nightfall, and how the halyards are fixed. If it looks like it will slap in a breeze and the boat is unattended , I climb on and re-fix the halyards.

Most people are fairly appreciative if I tell them and just are unaware of how to avoid it.

 

[sdowney717]

We love our vessel very dearly and spend a great deal of time aboard cruising around the North East coastline of New Zealand from our home base in Auckland.
When anchoring overnight we do go to some trouble to tuck well in to the weather shore if there is any breeze. We find that even a small chop generates what we call the Arrival of the Slappers. Sadly these are not fast young ladies but slapping noises from the chines. These are amplified by the hull acting as a sounding box and can result in a disturbed night's sleep.
I believe that this is a common problem on semi-displacement vessels and have observed some Mickey Mouse attempts to overcome this by attaching floating Noodles and other objects when at anchor.
I am looking for a more professional solution such as a partial infill along the chines. I understand that the main function of the chines is to deflect spray rather than to have a hydro-dynamic effect.
Any comments or advice from other owners would be most welcome.

Found this, says made it go away
SENTOA.org

 

[BruceK]

As Ski mentioned in post #2 anchoring from the stern should put an end to it. The chines are most often submerged at that end of the boat. May even have a positive effect on "sailing". However the wind over the stern may fill your boat w BBQ smells....
. I've been intending to try anchoring from the stern and still intend to do it mostly to see if sailing is less of a problem that way. Willy's rounded stern may cause slap noises but I doubt it....

Eric, I see people anchor or moor by the stern, usually I think to catch the sun into the cockpit on cooler days.Your Willard perhaps excepted, boats are not designed to do that,in a severe case you could get a lot more than bbq smells coming over the transom.

 

[Peter B]

That's true. I've spent many nights on rig sites with all kinds of racket. You just get used to it, especially if the noise is constant or repetitive. If the noise is intermittent, like a slapping halyard, I find it much more bothersome.

I normally look at my neighbouring sailboats before nightfall, and how the halyards are fixed. If it looks like it will slap in a breeze and the boat is unattended , I climb on and re-fix the halyards.

Most people are fairly appreciative if I tell them and just are unaware of how to avoid it.

Yes, that always amazed me how often even quite experienced yachties didn't automatically flick their halyards and topping lift out over the end of the spreader one side or the other before tensioning. If they just haul them straight down the mast then tie off, not matter how well tensioned, they are going to slap in a wind..!

 

[Trundlebug]

PeterB had the best answer to the problem in post #10.

Accept that you can't stop the noise, but you can reduce the volume with a bit of effort behind the scenes.
Insulate the affected area of the hull on the inside with sound absorbing material, so that the volume is diminished enough that the residual noise isn't enough to keep you awake.

I'm lucky enough to have a round bilged hull which is completely silent in all but the worst conditions.

 

[Ski in NC]

Eric, I see people anchor or moor by the stern, usually I think to catch the sun into the cockpit on cooler days.Your Willard perhaps excepted, boats are not designed to do that,in a severe case you could get a lot more than bbq smells coming over the transom.

No doubt that boats are not designed to take seas and weather from the rear end. Only when in known gentle conditions. And if a freak storm comes up, I use a "monkey" line to secure the rode to the stern cleat, easy to uncleat and release rode. Boat then swings around and hangs off the bow.

 

[Tom.B]

Insulate the affected area of the hull on the inside with sound absorbing material

I am curious if anyone has tried this with any success. It doesn't seem like it would work to me. It's not like a noisy car floor, so I don't know. Maybe I am wrong.

 

[Art]

For overriding chine slap noise maybe playing some good ol Janise Joplin or a lil bit o' Jimi Hendrix would take your mind off the sound.


Little Joke Here - Ah, sort of!

 

[Art]

For overriding chine slap noise maybe playing some good ol Janise Joplin or a lil bit o' Jimi Hendrix would take your mind off the sound.


Little Joke Here - Ah, sort of!

I'm lucky that my planning hull, 34' tri cabin Tollycraft has no slap noise. With other Tolly models I have read about chine slap.

Best luck in overcoming your slap noise problems.

 

[MichaelB1969]

Try this.

https://www.bedbathandbeyond.com/store/product/marpac-dohm-original-sound-conditioner-trade/3263995

Seriously.

 

[boater3]

So we've had our share of bad weather, strong winds/currents, and chine slap. Mostly used to it but on snotty days having fans/hvac/genset running seem to help. We try to not run the genset when we can though.

Florence - I am interested in details on your fully enclosed fly bridge!

 

[Florence]

Thanks for this mystery. We do not seem to be troubled by this any more. Perhaps our hearing is fading as the years progress. We do keep some ear plugs handy but I prefer not to use these as it reduces sensitivity to any adverse weather changes or happenings in the night.. Also I do take particular care when anchoring overnight and try to pick a good sheltered spot.
We had the enclosed flybridge fabricated by a local boatbuilder. Like most boat projects, this cost about double the original estimate. It has been a brilliant investment however, increasing the living space on the boat by about 40%. The only downside is that we are now designated Party Boat by all our friends! Cheers
PS Will dig out some pics if you are interested in further details.

 

[wkearney99]

For a powerboat we used to have I once used a pair of kids foam swim noodles to help silence chine slap. I strung a line through two noodles, with knots inline to hold their position on it. Then I draped that under the chines and attached it to some amidships cleats. Looked kinda strange but worked a treat. I don't know that I'd have done it regularly as the noodles tend to get nasty when left in the water for an extended time. That and having it scrape against the ablative paint under there would probably not be ideal. But for a 3am half-in-the-bag fix, it worked.

 

[Art]

To fully get away from disturbing chine slap - Sleep in master state room to rear of boat. A tri cabin accomplishes this nightly and nicely!

 

[boater3]

Thanks for this mystery. We do not seem to be troubled by this any more. Perhaps our hearing is fading as the years progress. We do keep some ear plugs handy but I prefer not to use these as it reduces sensitivity to any adverse weather changes or happenings in the night.. Also I do take particular care when anchoring overnight and try to pick a good sheltered spot.
We had the enclosed flybridge fabricated by a local boatbuilder. Like most boat projects, this cost about double the original estimate. It has been a brilliant investment however, increasing the living space on the boat by about 40%. The only downside is that we are now designated Party Boat by all our friends! Cheers
PS Will dig out some pics if you are interested in further details.

yes, pictures please!!!