Sound Deadening

[ianupton]

Been a while since I have been here.

I need to sound insulate my B20 Bahia. There are some higher pitched sounds as well as lower frequency. Engine is 4.3 Volvo Duoprop.

Reading alot about the thin products, Acoustiblok, Hushmat, etc. Any one actually tried these vs the standard Soundown or equilivant?

Thanks in advance.

Ian.

[Howesounder]

I don't know the brand names but I used a foil covered, 1 inch foam with an integral layer of barium that was very effective.

Steve

[Navatech]

I don't remember the name but at my last Miami boat show I saw something pretty thin but highly effective...

[Yannis]

I dont remember the name but my engine room was all jacketed with a foam/lead sheet/foam/alu foil sandwich which i mostly ripped and took out, anyway you cant hear anything up there. I made the boat at least 50 -100 kilos lighter. Im glad i did it.

[Tony Meola]

Ian

For the majority of us. Sound down has been the go to product. There used to be a sound down rep who would answer questions about there product. I know he would be bias, but he might be able to tell you some of the differences in products. Just don't remember how to contact him.

[Dug]

Guys,

I have recently become acquainted with a company here in MA that makes sound insulation that is very effective. They are a competitor of Soundown, but have never marketed themselves. Long story.

I asked if they might be willing to make and ship "kits" of pre-cut pieces that could be bought by boat owners and they readily agreed. Now all that is required is that I sit down and "design a kit".

I had planned to start with the Bertram 31, but I suppose any boat we like could be a candidate.

Thoughts? What would people be willing to pay? What does the sounddown kit cost? Its been a long time since I installed...

Dug

[Stephan]

Dug-
Part of my consideration is the expense and effectiveness of securing the sound deadening material in place.
It is my understanding that sounddown and similar products are installed with a combination of adhesives and brads that pierce the material. Because the material is relatively heavy and it is a hot environment the adhesives fail taking with them a portion of the top foam layer of the material and the brads work themselves bigger holes in the material. When I got my boat I spent a bunch of time cleaning up the residue of the old sound material. If this new company has material that installs or stays installed differently that would be of interest to me.
Stephan

[1962 31]

what about the stuff they use in cars
fatmat

[Yannis]

Whatever the material, it has to be covered by (usually) alufoil so it does not absorb water.

Stephan,

When i removed mine it was stuck in place with some glue, no brads. It was secured so well, it was impossible to remove it but in very small pieces, plus had to scrape the dried glue off.

[Carl]

I finally just ripped all mine out of the boat.

I never got around to completing full install on bulkheads so what I achieved was better but not quite great results. Need complete coverage to really deaden sound.
The stuff is also pretty heavy. Motors boxes on express need to be lifted straight up and brought inwards a bit to be able to pivot box backwards to gain access to motors. Having to lift box, several panels of sound proof material plus water that soaked in (foil tape gets ripped and scraped) became a major pain in my back...

After lifting several times this year, a usual edge caught when removing box( stuff is also thick)..instead of fixing I ripped it all out.

In short...if you do tackle the job make sure to do entire compartments to achieve desirable results. Areas I prepped correctly stayed very well put. Areas not quite prepped 100% I had to deal with again. Areas that get pushed, pulled as you work on motors...well as one would expect do not hold up very good. The stuff is pricey, heavy and takes up a good amount of space plus if you cut corners and stop short of finishing complete install...results are lacking.
Done right..it is a nice upgrade.
I used a sound down.

[Tony Meola]

Would love to find something that holds up.

Carl is right, my box's were heavy when the foam was on them. Eventually fell off and took a beating when you worked on the engines, unless you remove the cover each time, but who does that just to do minor work.

[scot]

I'm not certain of the dba reduction (effectiveness), but closed cell neoprene sheets are also marketed as sound deading. Not nearly as heavy as traditional sound deading material. We used it extensively in the commercial diving industry as flotation aids. One brand is Armaflex, Armacell. This sheet material is similar to hardware store pipe insulation, but the materials we used had a tougher skin than the pipe insulation, very durable. It had to be cut, wouldn't tear by hand.

Being closed cell neoprene, it absorbs no water. It also takes adhesives very well and stays where you put it. Not sure how it would do with heat? I wouldn't put it touching against a hot engine. It is not expensive compared to the Sound Down type materials, I assume because it is mainly used in industrial applications.

[Yannis]

Scot,

Like you said, armaflex is used for pipe insulation. It is also used for central heating pipes. The water temp in those reaches at least 80 o C. How hot can a motor become ? The meter shows 70 o C as a normal radiator water temp but i don't know if the metals get hotter than this.
I would tend to think however that sound deadening a motor would require " substance", the one provided by the metal sheet within the foam, something that armaflex doesn't have.
What i found VERY effective however is the thick cushion that i made that covers completely the top surface of the stbd engine. That engine is heard significantly less than the port one which is not covered by a cushion.

I would post a pic but i cannot find out how you can post pics from an i pad.

[Yannis]

This cushion is very sound deadening !!

[Navatech]

Just saw this and remembered this thread...

X-Mat Underhood and Headliner



Having said that, IMHO the top sound deadening (8 dB) doesn't seem worth the expense and trouble... I had a look at their other products in this line... http://search.eastwood.com/search?w=x-mat The top sound deadening is 19 dB...

[ianupton]

Thanks everyone. Been crazy busy.

Sounds like many options, but soundown is the tried and true.

I will try calling them today.

Again, thanks.

Ian.

[Tony Meola]

Guys,

I have recently become acquainted with a company here in MA that makes sound insulation that is very effective. They are a competitor of Soundown, but have never marketed themselves. Long story.

I asked if they might be willing to make and ship "kits" of pre-cut pieces that could be bought by boat owners and they readily agreed. Now all that is required is that I sit down and "design a kit".

I had planned to start with the Bertram 31, but I suppose any boat we like could be a candidate.

Thoughts? What would people be willing to pay? What does the sounddown kit cost? Its been a long time since I installed...

Dug

Dug

Are you going to use your friends product? Would love to hear how it works out.