Sound Proofing

[choogh]

I'm thinking to sound proof the engine room, either by boxing in the engine, or, by installing sound proof material to the steel work. The engine is an Isuzu 43hp, with hospital silencer. To the outside, there is hardly any noise, exhaust or otherwise, but stood on the counter, I hear all matter of clatter.. any thoughts, or suggestions.?

[Guest]

any thoughts, or suggestions.?

 

ear plugs..?

[choogh]

ear plugs..?

That would work..

[Robin2]

I'm thinking to sound proof the engine room, either by boxing in the engine, or, by installing sound proof material to the steel work. The engine is an Isuzu 43hp, with hospital silencer. To the outside, there is hardly any noise, exhaust or otherwise, but stood on the counter, I hear all matter of clatter.. any thoughts, or suggestions.?

 

I put 3M Thinsulate around most of my engine compartment including the underside of the hatch and decks and it makes a huge difference. Its easy to apply using some sort of contact adhesive - I got expensive water-based stuff made by 3M, it's a bit like Jiffytex.

[Guest]

That would work..

 

It would - but is your boat really as noisy as you think...??

 

I often hear passing boats and think 'goodness that is quiet' - but they are on the correct end of a hospital silencer, which you already have......

 

Boxing in a big powerful already installed Isuzu will not come cheap I reckon...

[choogh]

It would - but is your boat really as noisy as you think...??

 

I often hear passing boats and think 'goodness that is quiet' - but they are on the correct end of a hospital silencer, which you already have......

 

Boxing in a big powerful already installed Isuzu will not come cheap I reckon...

Your right, people can bearly hear when I pass, but if anyone try to call or talk to me from the towpath, I can't hear a damn thing for the engine noise coming from the ER.

[blackrose]

I'm thinking to sound proof the engine room, either by boxing in the engine, or, by installing sound proof material to the steel work. The engine is an Isuzu 43hp, with hospital silencer. To the outside, there is hardly any noise, exhaust or otherwise, but stood on the counter, I hear all matter of clatter.. any thoughts, or suggestions.?

 

Stood on the counter? Well it's bound to be fairly noisy if you're standing in the engine room or engine hole. (My understanding of "counter" is the flat plate that's above the curved swim - also called the uxter plate.)

 

Or did you mean when you're standing on the stern deck?

 

Noise (or unwanted sound), is transmitted by soundwaves in the air and also by vibrations through solid objects.

 

Since you don't hear much noise on the towpath I suspect that the noise you experience is transmitted through vibrations of solid objects. If that's the case then sound insulation will do little to reduce the noise. Are your deckboards or doors rattling for example? Or do you have some loose objects or other stuff down there that's vibrating? If so, you should try to cushion or eliminate those vibrations.

Edited August 15, 2011 by blackrose

[sharpness]

Stood on the counter? Well it's bound to be fairly noisy if you're standing in the engine room or engine hole. (My understanding of "counter" is the flat plate that's above the curved swim - also called the uxter plate.)

 

Or did you mean when you're standing on the stern deck?

 

I think he means the poop deck (though I'd have called it the counter as well)

 

Steve

[matty40s]

Stood on the counter? Well it's bound to be fairly noisy if you're standing in the engine room or engine hole. (My understanding of "counter" is the flat plate that's above the curved swim - also called the uxter plate.)

 

Or did you mean when you're standing on the stern deck?

 

Noise (or unwanted sound), is transmitted by soundwaves in the air and also by vibrations through solid objects.

 

Since you don't hear much noise on the towpath I suspect that the noise you experience is transmitted through vibrations of solid objects. If that's the case then sound insulation will do little to reduce the noise. Are your deckboards or doors rattling for example? If so, you should try to cushion or eliminate those vibrations.

 

bizzards Tip No 349 recommends a series of egg boxes (empty) wrapped in sheets of bubblewrap and installed around engine compartment. This can also double as survival craft in times of severe weed hatch malfunction.

[Machpoint005]

bizzards Tip No 349 recommends a series of egg boxes (empty) wrapped in sheets of bubblewrap and installed around engine compartment. This can also double as survival craft in times of severe weed hatch malfunction.

 

Bizzard presumably doesn't know (or care) about the fire risk, or the nasty poisonous fumes given off by smouldering bubblecrap.

 

Seriously, chaps, eggboxes are for eggs.

 

To 'soundproof' an engine:

 

1 Isolate it from its support structure (v. difficult where there's a rigid coupling to a propeller).

2 Seal it up in a nice box (great way to make it overheat).

3 Remove yourself from the noisier parts.

[bottle]

Sound insulation: Midland Chandlers (available elsewhere)

[Robin2]

Sound insulation: Midland Chandlers (available elsewhere)

 

The Thinsulate is easier to install.

[bizzard]

bizzards Tip No 349 recommends a series of egg boxes (empty) wrapped in sheets of bubblewrap and installed around engine compartment. This can also double as survival craft in times of severe weed hatch malfunction.

Better hurry up too.It looks like the Papier Mache type are on the way out,lots of plastic ones about now.

No fix for noise with my Lister st2,can't box em in much,they get hot and bothered.I am thinking of controlling my boat by radio control from a dinghy on a 100 yd tow rope to get away from it.bizzard

[bizzard]

Bizzard presumably doesn't know (or care) about the fire risk, or the nasty poisonous fumes given off by smouldering bubblecrap.

 

Seriously, chaps, eggboxes are for eggs.

 

To 'soundproof' an engine:

 

1 Isolate it from its support structure (v. difficult where there's a rigid coupling to a propeller).

2 Seal it up in a nice box (great way to make it overheat).

3 Remove yourself from the noisier parts.

Oi! This is a frame up. I wouldn't dream of doing such an absurd, ridiculous and dangerous thing.

There are too many folk on the forum with little sense of humour and so might take it literally,go ahead and do it and so cause themselves an injury.

Mind you there's nothing to stop people sticking all their old redundant Thinsulate bobble hats,long johns and socks inside their engine box.Or just wear one of those insect head aerodynamic type crash helmets,you can't hear much with those on,and the boat would go a bit faster too. bizzard.

[WotEver]

The Thinsulate is easier to install.

And less effective. We've had this conversation before.

 

I found the self-adhesive MC stuff incredibly easy to install; cut to size, stick onto panel. I can't imagine how it could be any easier.

 

Tony

[Robin2]

And less effective. We've had this conversation before.

 

I found the self-adhesive MC stuff incredibly easy to install; cut to size, stick onto panel. I can't imagine how it could be any easier.

 

Tony

 

I don't recall the previous conversation and I can't find it with a search. Do you recall it and can you provide a link please?

 

What I like about the Thinsulate is that you can cut it with a scissors and also, because it is soft, you can cut small bits and jam them into places you have missed and into holes where cables run through.

[Roger Crown]

I don't recall the previous conversation and I can't find it with a search. Do you recall it and can you provide a link please?

 

What I like about the Thinsulate is that you can cut it with a scissors and also, because it is soft, you can cut small bits and jam them into places you have missed and into holes where cables run through.

We always used the sandwich type of sound proof material from Classic Acoustics Ltd.

I fitted thinsulate sound proofing to our boat and have since ripped out the next to useless very expensive material and replaced it with the sandwich type.

 

Regards

Roger

[WotEver]

I don't recall the previous conversation and I can't find it with a search.

I can rarely find anything of relevance with a search either.

 

The difference with the MC stuff is firstly that it's much thicker - over 25mm - and secondly that it contains a heavy rubberised 'lead' layer sandwiched between the closed-cell sponge. So you have three effects from applying it:

 

1. It dampens any tendancy for the panel to 'drum'.

2. The foam absorbs high-frequency energy - the rattles and clangs.

3. The 'lead' layer dampens lower-frequency energy - the 'throb'.

 

I was absolutely amazed at the noise reduction I achieved with a less-than-complete coverage in our engine bay. The guy on the other side of the pntoon said "It sounds like you've fitted a new engine!".

 

Tony

[bottle]

My reply would have been the same as all above.

[Mike Jordan]

The correct purpose made material needs to be used to absorb some of the noise and stop it bouncing round all that steel, there isnt a cheap and cheerful method that realy works in my experience. But before spending on the triple layer material, you will get a huge reducion in noise levels if you seal the deck boards properly. This means hinging the boards and fitting budget locks to pull the boards down onto a strip of closed cell foam stuck to the underside of the boards and trapped between the steel drainage channels and the boards. To work effectively the steel needs to bite into the foam all round and make the joint air tight! The first time I did this was after spending a mint on sound reduction without real reward. The foam seal cost a fiver and did a great job.

Mike

[ditchcrawler]

I'm thinking to sound proof the engine room, either by boxing in the engine, or, by installing sound proof material to the steel work. The engine is an Isuzu 43hp, with hospital silencer. To the outside, there is hardly any noise, exhaust or otherwise, but stood on the counter, I hear all matter of clatter.. any thoughts, or suggestions.?

I would suggest this from ASAP Supplies

[choogh]

I would suggest this from ASAP Supplies

 

Thanks..but they are seriously expensive....

[Bimbly1]

Thanks..but they are seriously expensive....

Yes but I have found that you gets what you pays for.

[choogh]

Yes but I have found that you gets what you pays for.

Well.....not always.. Noise Killer Vibrasorb seems just as good (similar spec) at 2/3rds the price..

[TandC]

Recently I ahve installed sound proofing insulation material i purchased from a chap who fits sound studios i believe, he has lots of off-cuts in useable sizes. This stuff is 15mm - 25mm thick (dependent on sort you go for, obviously the price varies), dense rubber particles bonded together with a self adhesive backing - basically like really thick carpet underlay.

 

I have applied it underneath the deck boards on our cruiser-stern, then sandwiched it in with 12mm ply. These 'boxes' of sound proofing slot inside the steel channel bearers which hold the deck over the engine room. The slot where the gear stick comes out the deck board is sealed with door-brushes - these make a surprising difference to the noise coming out of that hole. I have used old bike innertubes to make rubber pads to isolate the boards from the steel channel bearers which has made a difference, so i will improve on that with a more permanent means - maybe pipe lagging or something across all the channel edges.

 

I cannot box the engine in more as it is air-cooled, and the sound of an SR2 thumping away is not something you can ever beat, but at least the ears bleed less now...

 

If you are interested, the guy i got 2 - 3m square of large off cuts for 60 quid ish i think, although it was some time ago. He lives ona boat up in Cogenhoe in NOrthampton adn can be contacted on:

 

point2acoustics followed by one of those little signs for at then the word hotmail then a dot then co then a dot and then uk.