Sound proofing material

[Liam]

Hi Brian,

Just picked up on this thread and I know what you want to do.

Anyway, yes to the expanding fam as it creates a tight barrier and also retains lightness that other materials wouldn't.

From using expanding foam in the past sadly not for ICE applications as Clayton said pratice before doing it because the rate off expansion would suprise you, so have patience and also be aware that messy parts can be rimmed with a knife when fully cured.

Keep us posted and good luck.

Liam

 

[DJ_Bucho]

Ok today was FOAM DAY! ! !

DJ you will go on the sound of my 1st whistle.
FOAM you will go when the DJ can get the can to spray

Ok here are the pictures of behind the quarter panel with the spray foam in place.

I'd just like to say thanks to "Clayton" for sugesting I do a practice spray, as first of all the can wouldn't spray at all, and I thought just my luck to pick a dodgy can.
I pressed the trigger REALLY hard and nothing happened I was well dissapointed, I was just on the point of giving up when BANG, I broke the seal and the foam started to spray, a good job I wasn't near the car when the seal broke as the Foam started blasting out of the end of the can. I quickly released the trigger, and did a quick practice on a scrap bit of cardboard, and in no time at all "I WAS A FOAM APPLYING GOD" .

The foam neatly applied to the gap, (expertly done I must say, ).

A close up of the the applied foam.

Behind where the rear seat belts mount, yes I've done a propper job, and sound proofed all the way back there as well.

I hope you like the pictures, more will follow, I'll keep you all updated.

Brian.

P.S. Thanks once again to "Clayton" for the advice.

 

[Clayton]

looking good son!

you'll hear nowt from outside soon when your finished!!

good luck.

 

[DJ_Bucho]

"Clayton" where abouts in Newcastle do you live?

Next time there is a meet at the Arnison Centre you should come down as Durham isn't that far away from you, and it'd be nice to see another member of the forum.

Brian

 

[Julio_Scorchio]

Having looked at all the loft insulation and talked to one of the chaps there, they said that loft insulation wasn't really what I was after as its designed to contain heat and wouldn't really do anything to contain the sound of speakers, so I headed for the spray expanding foam.
Brian

Just to clarify some principles: The density of a material will define its thermal or sound absorption characteristics.

For good thermal insulation, you need to trap pockets of gas/air in order to create little thermal barriers. These barriers help to stop the transfer of heat from one place to another, and you can generally tell what is going to be a good thermal insulator by touching the material - if it feels warm, it isn't transferring heat so is a good THERMAL insulator. (eg: polystyrene foam, loft inulation)

For good sound insulation, you need a much denser material, in fact, the denser (and generally heavier) the better the sound absorption properties. Think of brick or concrete walls and thick glass as being good, caravan walls for example not being good. Lead is an ideal sound insulator, - not good for a wee cinq, but OK for a Hummer. The denser the material, the better the sound absorption properties. You can generally tell a dense material by it's weight, and it often has a tendency to feel cold.

HTH

Tosh

 

[Clayton]

Brian mate. Never been to arniston yet. I have got a few mates who travel across there every weekend. I am normally drunk u see. And I didn't really want to go until my car was more modded rather then in its current state!

I don't technically lie in newcastle. Live in Hexham mate.

 

[DJ_Bucho]

Oh right well Haxham isn't really that far away, well one time if we give you plenty of notice you will have to be sober and come across one time, don't worry about ya car, there's a few people that haven't got modded cars and just come along to socialise.

It would be good to see you there one time.

Hope you think about it mate.

Brian

 

[Clayton]

Yeah I will think about mate.

Cheers!

 

[arv]

get this

 

[Daryl]

all it is is that wether band stuff u use for doing shed roofs its cheep and the same as dino mat

 

[Clayton]

think your right there daryl mate.

Thing is you don't need anything special for sound deadening. just something heavy and sticky will do.!

 

[DJ_Bucho]

Ok, I've finally put my car is back together, after what seems like an eternity without my quarter panels, rear seats, seat brackets, rear seatbelts in fact any rear interior at all.

Anyway on Tuesday Dave (Peaster_2k) and I, went to "Dainty toys" to see what type of stuffing materials they had. Dainty toys sells all sorts of material for making and repairing toys, so after making enquiries into the different densities of stuffing material that they sold, I decided to purchase two large bags of the most dense material that they sold.

Back at Dave's we decided to get underway, upon closer inspection it turned out that the bags I bought were really well stuffed, and as soon as they were undone, the material started to burst out of them. This meant that in fact I only actually needed one bag instead of the two I purchased. Despite Dave’s valiant attempts to get the stuffing material to the front of the car by stuffing hand-full after hand-full of material into the sill via the gap behind the quarter panel. I also managed to use what seemed like mountains of the material but shoving it as far up the B and C pillars as I could.

After doing all of this on both side of the car, we still only managed to use one complete bag of the material, but Dave decided that when he comes to sound proof his car, he’ll use the same material, so he bought the remaining bag from me.

The car is now so much quieter than before, you can hardly tell I have a 4-2-1 manifold, de-cat pipe, and sports back box on it at all, well from inside the car anyway.

Pictures will be following very shortly, but unfortunately the only one I have at the moment is from Dave and is of the remaining bag of stuffing material.

Brian

 

[The Negotiator]

Just to clarify some principles: The density of a material will define its thermal or sound absorption characteristics.

For good thermal insulation, you need to trap pockets of gas/air in order to create little thermal barriers. These barriers help to stop the transfer of heat from one place to another, and you can generally tell what is going to be a good thermal insulator by touching the material - if it feels warm, it isn't transferring heat so is a good THERMAL insulator. (eg: polystyrene foam, loft inulation)

For good sound insulation, you need a much denser material, in fact, the denser (and generally heavier) the better the sound absorption properties. Think of brick or concrete walls and thick glass as being good, caravan walls for example not being good. Lead is an ideal sound insulator, - not good for a wee cinq, but OK for a Hummer. The denser the material, the better the sound absorption properties. You can generally tell a dense material by it's weight, and it often has a tendency to feel cold.

HTH

Tosh

I have to disagree with this, although I only have A level standard education, the best sound proofing materials are fibrerous and porous materials. This is because it will attenuate the sound moving between the interfaces. Of course it depends if you want the sound reflected (requires high densities as you say, such as concrete or soil sound barriers) or absorbed (fibrerous materials)

Specifically you said:
"The denser the material, the better the sound absorption properties." -- From what I know, this is wrong....?

I am correct:

The more fibrous a material is the better the absorption; conversely denser materials are less absorptive.

Denser materials transmit sound better, hence why sound travels down a tin can and string "telephone" better than it does through speaking the same volumes simply due to the molecules being closer together.

 

[Clayton]

i think u have a point there. and just to add my little point.the denser and thicker the material it may absorb the sound more but not reflect it and hence not being best for car audio where u want all the sound reflected back inside not lost when it all is absorbed in formy crap.

bullet proof glass is very thing. kevlar is quite light. hmm...if only i was very clever i could maybe understand all this.

 

[The Negotiator]

i think u have a point there. and just to add my little point.the denser and thicker the material it may absorb the sound more but not reflect it and hence not being best for car audio where u want all the sound reflected back inside not lost when it all is absorbed in formy crap.

I am trying to say this is wrong, the denser the material the less it absorbs (less air gaps) and the more it reflects. Absorption relies on a material being pourous for attenuation, reflection relies on a different sort of interface (in my course, we concentrated on absorption and active noise control, not reflection, so can't comment much on that!) However, I also can't comment on what would be required in the car as I don't actually know the desired outcome of it lol. If it was proofing through remving energy, something like a foam works and if reflection, something dense would work I was specifically disagreeing with that single "The denser the material, the more it absorbed"

 

[Clayton]

haha right then paul.
Then you are very correct in disagreeing with that line!!!
that line is now a pile of crap.

 

[The Negotiator]

Hey I might be wrong, i mean 2 years ago I thought you could only have 8 electrons on an orbital and didn't know you could have sub-orbitals on atoms but then they tell you "we over-simplified it because you were only doing GCSE" - Maybe it's the same for this...

 

[Clayton]

Hey I might be wrong, i mean 2 years ago I thought you could only have 8 electrons on an orbital and didn't know you could have sub-orbitals on atoms but then they tell you "we over-simplified it because you were only doing GCSE" - Maybe it's the same for this...

I gave up all sciences after gcse and so still believe this to be correct.

 

[Julio_Scorchio]

I am trying to say this is wrong, the denser the material the less it absorbs (less air gaps) and the more it reflects. Absorption relies on a material being pourous for attenuation, reflection relies on a different sort of interface (in my course, we concentrated on absorption and active noise control, not reflection, so can't comment much on that!) However, I also can't comment on what would be required in the car as I don't actually know the desired outcome of it lol. If it was proofing through remving energy, something like a foam works and if reflection, something dense would work I was specifically disagreeing with that single "The denser the material, the more it absorbed"

I think we may be both agreeing and disagreeing with each other here. My comment could have been a little clearer as to the type of sound absorption.

I completely accept that if we are talking about, for example, concert halls, then the wall and ceiling material would preferably be a lighter, more open surfaced material to 'absorb' sound by allowing it to pass through and subsequently prevent it being reflected back into the auditorium. A person on the other side of the ceiling tile would hear the sound almost unabated, as the sound would not be 'absorbed' by the material.

For a semi-detached house, however, your stereo system would drive the neighbours mad if the walls were very lightweight, because they would do the same as the aforementioned ceiling. In that case, a nice heavy brick or block would 'absorb' the sound by effectively cutting down the pass-through volume, but would do as you say and reflect the sound back into the room.

(All of this is, of course, dependent upon the thickness of the material, ie: 50mm of polystyrene vs 50mm of Brown Bread for example)

Your sub box, for example, is made out of heavy MDF and thick fibreglass, so as to form a solid enclosure, and give the best sound whilst preventing any buzzing or vibration. The density helps channel the sound, increasing the sub's effect.

Perhaps I was a little at cross-purposes and could have been clearer. What I meant was the choice of material dictates the 'pass-through' qualities of the insulation, whereas you are talking more about the 'reflective' qualities. So in that case, your comment is entirely correct. I can certainly see what you mean in the context of the reflective qualities of sound-proofing materials.

It's easy to see how misunderstandings occur. Sorry for the confusion.

Tosh
(Definitely not trying to start a flame war)