Sound deadening foam?

leaky

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I'm gonna need some relatively soon, starting to put thought into my engine box. Immediately when I get into that going to have to figure out clearance, how I want to attach the stuff, gonna need to order some and get familiar with it.

Anyone using a brand other than sound down? Which if so and where you getting it?

It's a gas engine. The thicker the insulation, the wider the box, so I'll be balancing these aspects.

Seems like a lot of options are out there, never messed with the stuff so not really sure what I'm looking for even.
 

goin4broke

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Whatever you get make sure it is heat and flame resistant. If I'm not mistaken you have an engine box? Lots of heat build up on a hot summer day. Some people out there propose the egg crate stuff they use in studio's. I wouldn't line my garbage can with that shit.

I know our mechanical guys use a blanket style for wrapping steam lines but, for the life of me I can't recall what it is.

Probably the cheapest option
 

Roccus

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Following this. I have 1” sound down but not totally sealed on my engine box and it’s really loud. I’ve contacted sound down for advice and which products to purchase from them several times with no response.
 

leaky

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I see a lot of versions of 3/8 (10mm) sound + heat shield out there. Kinda a standard material apparently.

Seems like a couple layers of something like this maybe in the ballpark. Absolutely no feeling for what the heck might work though.

LINGDA 21.53 SqFT 10mm Heat Shield Thermal Sound Insulation Proofing Deadener Mat Car Noise Control Acoustic Dampening Moistureproof Waterproof (40"X80") https://a.co/d/0IgBiAb
 

leaky

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Whatever you get make sure it is heat and flame resistant. If I'm not mistaken you have an engine box? Lots of heat build up on a hot summer day. Some people out there propose the egg crate stuff they use in studio's. I wouldn't line my garbage can with that shit.

I know our mechanical guys use a blanket style for wrapping steam lines but, for the life of me I can't recall what it is.

Probably the cheapest option
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Thanks and yes correct on the engine box. May also line the underside of the deck panels around there too. And a generator housing with similar considerations.

Engine splits the bulkhead, so actually are 2 boxes that mate to bulkhead on opposite sides going in. I designed it all so outside air, inside air, are generally sealed off - I say generally in the sense of things like outboard motorwell boots clamp down around hoses and wires that pass from one side to other, and of course the engine box is a seal in the same sense (no vents go on it).
 

leaky

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Jon- I get my sound down from a place called General Insulation company. The branch I source from is in the Seattle area, but they may have a location close to you, if you search their website. They have always been great to work with in my experience. Insulation Products - General Insulation Company

Do you remember what sorta thickness & sort you used? Appears they make a couple styles, foam and vinyl.
 

Jjammer

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Following this. I have 1” sound down but not totally sealed on my engine box and it’s really loud. I’ve contacted sound down for advice and which products to purchase from them several times with no response.
Who are you contacting ?

Call and ask for Dan or Matt both are awesome

2” for engine box on diesel typically

Gasket the box so no big air leaks to the deck.

Entomb the engine bay and baffle your intake air if you want to go next level
 

Capecodfisherman

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I have a 45 ft novi, im not sure what soundown brand I have , but it seems they put some sort of thin 3/8” composite board over the beams in my engine room and it’s extremely quiet. Like I can have a normal conversation in my wheelhouse while steaming. I wish I could be more specific but maybe some of the builders on here or a call up north to wedgeport or another builder could give you a better idea. It would also be a good way to encase it so you’re not relying on glue alone.
 

leaky

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I have a 45 ft novi, im not sure what soundown brand I have , but it seems they put some sort of thin 3/8” composite board over the beams in my engine room and it’s extremely quiet. Like I can have a normal conversation in my wheelhouse while steaming. I wish I could be more specific but maybe some of the builders on here or a call up north to wedgeport or another builder could give you a better idea. It would also be a good way to encase it so you’re not relying on glue alone.

When I make the engine box, it will probably be more of a technical light foam cored box for ease of moving it around - in the cabin it's actually gotta lift up to come out/off. But I'll probably put some strips of wood mixed into the foam, so that I've got something good in there to screw into.
 

Jjammer

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When I make the engine box, it will probably be more of a technical light foam cored box for ease of moving it around - in the cabin it's actually gotta lift up to come out/off. But I'll probably put some strips of wood mixed into the foam, so that I've got something good in there to screw into.
Mass is your friend on the engine box in terms of sound reduction
 

leaky

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Mass is your friend on the engine box in terms of sound reduction

I will consider doing it out of Coosa. Might workout better that way.

A few of these parts that aren't actually part of the boat I'm planning on pushing some limits on - as worst scenario they are just removed, improved/repaired, replaced etc.

Engine boxes, both ends, do actually gotta get lifted off and carried or set down elsewhere - no where to slide them to. 20 lbs in human terms would be a huge difference when you go to lift them. And it's a lot of panel in a box, ballpark > 1/2 a sheet, where it's gotta be stiff enough to stand on but not really durable. That strikes me as straight fiberglass cloth over light core, which is a compromise on sound proofing of course :).

Regardless of what it's made from the acoustic foam I figure is helpful and goes in there.
 

Jjammer

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I will consider doing it out of Coosa. Might workout better that way.

A few of these parts that aren't actually part of the boat I'm planning on pushing some limits on - as worst scenario they are just removed, improved/repaired, replaced etc.

Engine boxes, both ends, do actually gotta get lifted off and carried or set down elsewhere - no where to slide them to. 20 lbs in human terms would be a huge difference when you go to lift them. And it's a lot of panel in a box, ballpark > 1/2 a sheet, where it's gotta be stiff enough to stand on but not really durable. That strikes me as straight fiberglass cloth over light core, which is a compromise on sound proofing of course :).

Regardless of what it's made from the acoustic foam I figure is helpful and goes in there.
Can you hinge the box? So it tilts back ?
 

leaky

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Can you hinge the box? So it tilts back ?

Maybe, possibly with pins to yank for full removal, on the box next to the helm. It would about touch the winterback though. Tight AF. Was considering that. Isn't that I couldn't lift even an 80 lb box either, just more awkward.

On the cabin side. SOL there - straight up, then sits on bunk. But it need not be so quiet in the cabin, if someone is tired enough they will find a way to ignore it, and we don't need to be carrying on conversation while dropping a duece.
 

chortle

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Maybe, possibly with pins to yank for full removal, on the box next to the helm. It would about touch the winterback though. Tight AF. Was considering that. Isn't that I couldn't lift even an 80 lb box either, just more awkward.

On the cabin side. SOL there - straight up, then sits on bunk. But it need not be so quiet in the cabin, if someone is tired enough they will find a way to ignore it, and we don't need to be carrying on conversation while dropping a duece.
Can you build a freestanding frame around the engine that the side and top panels attach to? Two sides, two ends, one top? Each panel attaches individually to the frame.
 

sammdawson

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I'm about to do a similar project. The research I've done has lead me to Sound Down + additional layers of mass loaded vinyl where you can fit it. The vinyl is beneficial because it is 1/8" thin and as the name suggests, very heavy. The benefit of the Sound Down is you have the MLV for deadening and the foam for isolation. Air gapping the MLV is also effective. You can buy MLV in rolls from Amazon etc
 

leaky

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Can you build a freestanding frame around the engine that the side and top panels attach to? Two sides, two ends, one top? Each panel attaches individually to the frame.

Probably could but for sure, it's gotta come right off if need be.

A simpler version of that idea - the top panel could, which is the biggest rock. You'd have the 3 bottom panels one piece, top sitting atop them as a separate part. But I'm probably gonna keep it simple, pick a way, rebuild it another way if I'm unhappy.

Ballpark math says, Divynicell cored 20 lbs, Coosa 38 lbs. The way I'd go at it, before sound deadening material. 18 square feet, less glass on the Coosa, more on the Divinycell. About 1 lb square foot difference.

I'm about to do a similar project. The research I've done has lead me to Sound Down + additional layers of mass loaded vinyl where you can fit it. The vinyl is beneficial because it is 1/8" thin and as the name suggests, very heavy. The benefit of the Sound Down is you have the MLV for deadening and the foam for isolation. Air gapping the MLV is also effective. You can buy MLV in rolls from Amazon etc

A good question might be is MLV sound deadening material more effective than Coosa versus Divynicell core. As it's about the same weight. Ie I could add 1 lb square foot MLV to a Divynicell cored version, it'd be identical weight to a Coosa version. What would perform best?
 

sammdawson

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A good question might be is MLV sound deadening material more effective than Coosa versus Divynicell core. As it's about the same weight. Ie I could add 1 lb square foot MLV to a Divynicell cored version, it'd be identical weight to a Coosa version. What would perform best?
I haven't tested the above comparison but everything I've read would make me think MLV + Divynicell will be more effective. Acoustiblok has good information on their website re MLV effectiveness. The efficacy is from the mass and also the transfer of sound energy to kinetic energy (so they claim). The foam cells in the Divynicell paired with MLV could be a good combo
 

leaky

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I haven't tested the above comparison but everything I've read would make me think MLV + Divynicell will be more effective. Acoustiblok has good information on their website re MLV effectiveness. The efficacy is from the mass and also the transfer of sound energy to kinetic energy (so they claim). The foam cells in the Divynicell paired with MLV could be a good combo

Thanks for that.

I was just playing with my dumbells. I'd say for such an awkward object, weight budget is 50 lbs here. Now that could involve a removable top, making it really easy as the top is a lot of the trick (making it support a human), but then I might just make it worse by introducing a gap.

Seems though if I kept the object to 20 lbs I ought to be able to line with 18 square feet of 1 lb MLV, plus some acoustic foam, and would stay in that budget.

And not that I can't lift a 200 lb object off the ground and put it on my shoulder, just not one shaped like an oven inside of a cramped and rocking pilot house :)
 


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