TheSamba.com :: View topic - Sound Deadening

Thu Jan 16, 2014 2:13 pm

My Vanagon is pretty quiet. It has some highway noise making it hard to have conversations with the rear passengers at times.

I'm hoping to tame the sound just a bit. I'm hoping to do 25% FatMat on everything, covering that with a closed cell foam 1/8", and covering that with some MLV.

I'm totally new to sound proofing so I could use some help. I found some local dealer of MLV ($140 for 100sq ft), but I don't know where to find closed cell foam. Is eBay a good source?

Have any of you tried this approach? Any tips for the Vanagon specifically?

Thu Jan 16, 2014 2:26 pm

Some good info here

http://www.raamaudio.com/pages/How%252dTo.html

A bit overkill in some aspects but you get the idea. They sell peel and stick 1/8" Ensolite closed cell foam.

Thu Jan 16, 2014 2:57 pm

madspaniard wrote: Some good info here

http://www.raamaudio.com/pages/How%252dTo.html

A bit overkill in some aspects but you get the idea. They sell peel and stick 1/8" Ensolite closed cell foam.

That stuff looks great, but it also costs about 3 x cheap closed cell foam:

http://amzn.to/1b6JdOU

From what I have read, the MLV is probably the most important for noise reduction, so I may not want to spend a lot on closed cell foam.

Thu Jan 16, 2014 4:47 pm

If you want cheaper you can do what I did, 1/2" closed cell foam blue camping mats. Walmart.

Thu Jan 16, 2014 4:54 pm

madspaniard wrote: If you want cheaper you can do what I did, 1/2" closed cell foam blue camping mats. Walmart.

What MadSpaniard said. Don't buy regular hardware store spray on glue. Go to a foam supplier or upholstery shop and get the good stuff. A little more $$ but it actually works. I got a roll of CCF there too for cheap.

Thu Jan 16, 2014 8:15 pm

singler3360 wrote: madspaniard wrote: If you want cheaper you can do what I did, 1/2" closed cell foam blue camping mats. Walmart.

What MadSpaniard said. Don't buy regular hardware store spray on glue. Go to a foam supplier or upholstery shop and get the good stuff. A little more $$ but it actually works. I got a roll of CCF there too for cheap.

Is spray on glue to stick the CCF to the panels? And also for the MLV to stick to the CCF?

I read velcro works well too.

Fri Jan 17, 2014 12:23 am

I used a bunch of fat yoga mats from the dollar store, and some thicker foam mat where there was room (like the camping ground mats but bigger). Cheap and seemed to work just fine. Spray glue was useless, ended up using staples into the door panel cards and self tapping screws in a few places. About half done now, my mlv was about double the cost of yours after shipping. Big difference so far, but not there yet.

Fri Jan 17, 2014 2:50 am

the yoga mats we have here all soak up water (they are not closed cell foam)

Fri Jan 17, 2014 11:06 am

Leipo wrote: the yoga mats we have here all soak up water (they are not closed cell foam)

they are probably partially closed cell foam not real closed cell foam

Fri Jan 17, 2014 1:35 pm

Foam is not a great sound deadener for use in cars. Heavy tar matts are more effective in reducing car noise, the idea is to dampen vibration of the sheet metal body panels, as their vibrations are what is transmitting a lot of the noise. heavy mass added to the body panels does a good job at dampening vibrations. Sheets of lead are even better (but a tad heavy for an underpowered van) The trick is to adhere tar matts all over their rear surface to make good contact with the body panel. Light weight foam is not effective at dampening these transmitted vibrations. Foam is good for temperature control (ignoring rust issues) but not good at deadening noisy panels.

What is MLV?

Fri Jan 17, 2014 1:51 pm

Don't use tar matts; use butyl matts for the sound deadening part.

The next layer in to do anything is the MLV, mass loaded vinyl. It needs to be sealed carefully to make a solid sheet - no gaps. MLV 'traps' the sound waves and prevents them from reaching your ears.

The foam is to float the MLV away from the panel.

Fri Jan 17, 2014 2:01 pm

bluebus86 wrote: Foam is not a great sound deadener for use in cars. Heavy tar matts are more effective in reducing car noise, the idea is to dampen vibration of the sheet metal body panels, as their vibrations are what is transmitting a lot of the noise. heavy mass added to the body panels does a good job at dampening vibrations. Sheets of lead are even better (but a tad heavy for an underpowered van) The trick is to adhere tar matts all over their rear surface to make good contact with the body panel. Light weight foam is not effective at dampening these transmitted vibrations. Foam is good for temperature control (ignoring rust issues) but not good at deadening noisy panels.

What is MLV?

MLV = mass loaded vinyl

The OP already mentioned he is using FatMat (not really tar matts). Thin closed cell foam is used in combination with Fatmat (or similar) and MLV. Thicker closed cell foam is also added in the panels for thermal insulation.

Fri Jan 17, 2014 6:04 pm

I used the yoga mats to Decouple the mlv ,it's not against the body metal, just the door panels,,, seems like it should be fine. Seems like a more price effective solution that buying the$$$ bonded ccf mlv.
I'm going to drop one of the mats in the bath tub to see how much it sucks up!

Sat Jan 25, 2014 11:50 pm

So tonight I took off the sliding door panel. I created an MLV panel and attached some ensolite peel and stick CCF. But getting the tabs to hold with the thickness of the MLV + CCF was impossible. I gave up and will keep working tomorrow. I started with holes that were about 2 cm, and now I have holes that are about 1" and the tabs are still not holding. A bit frustrating, but I'm sure I'll get there.

Next up is the front doors, and then I may try under the rear bench. Then I'll get the front carpet area.

Sun Jan 26, 2014 10:18 am

I've been thinking about picking up some of this stuff to try when I finally decide to dive into this project: http://www.lobucrod.com/index.html

Sun Jan 26, 2014 12:01 pm

Solrider wrote: I've been thinking about picking up some of this stuff to try when I finally decide to dive into this project: http://www.lobucrod.com/index.html

Looks like the same as this http://www.insulation4less.com/Insulation4lessProduct-20-Prodex-Total-4-ft-x-50-ft.aspx

maybe a little less expensive

Sun Jan 26, 2014 12:37 pm

http://www.atticfoil.com/technical-information/r-value.html

read their home page also

these products will not give any dampening of the panel and are mostly a "barrier" to radiative heat flow, which is minimal for the sides of a Van anyway, and probably minimal for the roof also

there is some stuff that is designed specifically for the interior of door panels - you stick it on and then use a heat gun to help mold it to the contour

Mon Mar 17, 2014 9:53 am

I just picked up two 3x5 grey ribbed "work cushion mats", made out of thick, closed-cell foam material. I've only placed one over my engine compartment and it's already made a difference. The rest will go under the seats, inside of cabinets, etc.

Bear in mind I have an I-4 ABA block conversion, so the engine noise has more high frequencies which the heavy mat absorbs excellently.

Mon Mar 17, 2014 10:31 am

When people are doing their door-panels, are they putting the CCF and MLV on the interior (just under the westy panel), but with the Butyl stick-on stuff on the outer skin of the door?

it is tough access into the door cavity up-front, so I'm only getting 25-30% coverage there right now. No way I can get in there with CCF+MLV in a 100% sealed coverage unit.

So i'm thinking you could stick the stuff onto the back of the door-card (grey/beige, backed by some kind of particle-board with water stains most likely), but then the thickness is impacted and the clips won't hold the door panel on anymore?

Mon Mar 17, 2014 11:29 am

nothing goes on the back of the door card

1/4 to 1/3 of the area of the outer door skin needs to be covered with a dampening material ("butyl" stick-ons or whatever; just don't use an asphaltic product)

you could put MLV in the door or just use a purpose designed product that replaces the thin plastic waterproof liner

look at the inner door frame and it should be obvious that it cannot resonate much - tap on it and you will confirm the lack of resonance there