Chicane67 --have dacron, now what!

[Seakane]

Another trick:



Go to the 'yardage store' and but a good length of Dacron, like 20-30 yards (its really cheap). Then stuff, not layer, the head liner, b-pillars, rear seat halfs and the aera just beneath the b-pillars. It will cut down on the road noise more than you can imagine.

The best part.....it weights almost nothing.

Chicane67 posted this a ways back on a different forum and I'm ready to try it out. Floorpans scrubbend and POR-15'd, seam sealed and starting on the Fatmatting. Yesterday we bought around 20yds of Dacron batting and are ready to start stuffing it into the areas mentioned above.

What area is considered the b-pillar? when you say to stuff and not layer the headliner --did you have any lumpy headliner problems afterward? Is it supposed to be fluffy in there or packed in tightly? The headliner is out now and I was thinking of stuffing the areas on the side that the headliner bows stick into. --rather /everything/ is out now and I don't want to miss an area. Cram and Jam, or leave it "poofy" like fiberglass insulation in the walls of a house?

Thanks in advance!
Aaron

[Tom Welch]

I bet if it is layered under the headliner it would work pretty good. I would try stuffing it in all the cracks along the edges and into the area behind the sail panels

[chicane67]

What area is considered the b-pillar? when you say to stuff and not layer the headliner --did you have any lumpy headliner problems afterward? Is it supposed to be fluffy in there or packed in tightly? The headliner is out now and I was thinking of stuffing the areas on the side that the headliner bows stick into. --rather /everything/ is out now and I don't want to miss an area. Cram and Jam, or leave it "poofy" like fiberglass insulation in the walls of a house?

The 'b-pillar' is the rear extension from the roof line down to the rear fender. You can take the 'sail panel's loose and stuff that material into the cavity and reinstall. As for the head liner, I just stuffed the material in from the sides (with the headliner installed except for the ends near the upper door seams) enough until it started bunching and looking lumpy. I also stuffed the area just below the b-pillar that goes over the rear inner fenderwell, going into the rear fender/trunk areas. A layer under the 'package tray' and stuffed the rear seat halfs. In addition, I also had the delux interrior, so I layered under the arm rests.

The idea behind sound absorbtion is to knock down the sound waves, so having an uneven surface breaks up the waves easier. The idea behind deadners like B-bag and Dynomat is to is to dampen panel resonance on longer panel areas. I never did stuff the cavities where the headliner 'bow's attach, but you are right.... its better to get it installed where you can.

Using them in combination has had the best overall performance that I have used, starting way back in my days of high-end mobile audio in the middle 80's. You dont really have to "full sheet" entire surfaces, but the roof and firewall were my exceptions to that and I used Dynomat's 'ultra light' roof material. The rest you can just install sections onto longer panels to reduce panel resonance...... unless you just feel like doing full sheet installs. That will make a big difference, but it does add weight and chews up your moola. Best parts about Dacron is, its cheap and weights next to nothing.

Let us know how it goes.

[Seakane]

Hey thanks!

We're on it today. as far as the b-pillars and other areas, should I cram it in so it's packed up in there or leave it fluffed out?

-A

[Seakane]

Ok, don't laugh, but I've been "testing" the acoustical properties of Dacron. (polyester batting).

My data has been scientifically gathered by pressing the material to my face and making motor noises (ud'n UD'N!) into my big roll of dacron as I wander around the apartment. My first observation is that this causes my wife to involuntarily roll her eyes. Second observation is that I don't really notice any reduction in sound with it vs. without it. Thinking maybe I was too close to the problem, I got my wife to perform the same experiment.

In this case I first observed that my motor noises are defiantly bigger than her motor noises. She may have been making honda noises or something. None the less, we couldn't hear a real difference with and without the material for her either.

Maybe I'm misunderstanding what it's supposed to do. Maybe it's more of a higher frequency road noise that it blocks as opposed to our pseudo-motor noises.

I can't see it hurting so I'm going to go ahead and use it. Too bad we can't get a side-by-side comparison and use a sound meter. No way I'm going to assemble the car, meter it and then tear out the headliner and sail panels and go to stuffing it in for a comparison.

[chicane67]

Hey thanks!

We're on it today. as far as the b-pillars and other areas, should I cram it in so it's packed up in there or leave it fluffed out?

-A

Pack it in there.

Next, if you really feel experimental.....take the wife and a bottle of Wesson...... OOPS, wrong experiment. Take a card board box, and place it over your head. Make your noises or whatever, and then line it with the Dacron and repeat noises..... or whatever.

The thing about your previous experiment, is that you were trying to muffle direct standing waves. The problem of your test is, that what you are doing with the Dacron, doesnt have to do with standing waves..... but more to the point of indirect accoustical reflections and dampening low frequency wave muddle.

I'll try and give you an idea of what I am talking about. A passenger compartment has particular dimensions--indeed, the arithmetic multiples of its height, width, and length--plus its unique mixture of hard (reflective) and soft (absorbent) surfaces will have profound effects on the quality of the sounds you perceive to your ears. You are mearly improving the environments head room by applying simple and cost effective absorbant materials. Youll hear the difference when you get to the first few test drives after you are done with the build.

[Jagarang]

Ok, don't laugh, but I've been "testing" the acoustical properties of Dacron. (polyester batting).

My data has been scientifically gathered by pressing the material to my face and making motor noises (ud'n UD'N!) into my big roll of dacron as I wander around the apartment. My first observation is that this causes my wife to involuntarily roll her eyes. Second observation is that I don't really notice any reduction in sound with it vs. without it. Thinking maybe I was too close to the problem, I got my wife to perform the same experiment.

In this case I first observed that my motor noises are defiantly bigger than her motor noises. She may have been making honda noises or something. None the less, we couldn't hear a real difference with and without the material for her either.

Maybe I'm misunderstanding what it's supposed to do. Maybe it's more of a higher frequency road noise that it blocks as opposed to our pseudo-motor noises.

I can't see it hurting so I'm going to go ahead and use it. Too bad we can't get a side-by-side comparison and use a sound meter. No way I'm going to assemble the car, meter it and then tear out the headliner and sail panels and go to stuffing it in for a comparison.

I'll tell my wife it's a solid scientific experiment with indespensable humanitarian consequences! I'll also mention that I will never be able to validate our findings without taking numerous photos of her as she strolls around with a roll a batting pressed to her noggin, and then post her on the net for the scientific community to gape at in wonder!

[Seakane]

Ok, so here is what we did today. My helper brought the digi-cam per Jagarang's request and did some documentation as we went along.



We went ahead and jammed it into the "ring" around the roof. We stuffed in between the ring and roof skin front, back and both sides, and also into the holes shown in the picture of the ring (installed with modified coat hanger).




We also stuffed the channels and empty pockets of the trunk/rear seat divider before we added a full layer of Rattletrap.





Rattletrap is FatMat's premium dampening pad. It was around $170 --$200 delivered for 70 sq ft. Definitely good stuff. Unfortunately, like most everybody else, I haven't tried a side by side comparison with Dynamant or Brownbread. These guys claim to be the thickest and the best, but who knows. I know they're at least half right at .100" thick!



Oh yeah, the area between the metal web of the divider is filled in with a layer of the truck bed liner. I had the whole trunk spayed a while back. The car is way quieter than when it had an interior with the truck liner even though I've still not installed the rear seats. Definatly helped --and water proofed besides.

Lastly, concerned about durabilitylity of the Dacron itself, I went ahead and threw a sample 6" square in the oven. Ran the oven up to 140 --which I doubt interiors see under the worst of conditions. All was well so I ran it up to 250 degrees and left it there for an hour. When I pulled it out it felt exactly like it did when it went in. I actually couldn't feel any heat from it when I lifted it from the cookie sheet directly from the oven. Not that I expected any crazy results but thought I'd check to see if it withered or disintegrated with high heat. No problems there. We'll see what ten years or more brings. I know it'd be a bugger to get it out of the areas we've stuffed so far.

Now to figure out how to stuff the b-pillars and keep it from scooting into the trunk and window quarter areas...

Hey, let me know if this was too much blabbing and photoage and I'll quiet down.

[Jagarang]

Your dating KILROY!!!!!

[hotroddr]

Just found this thread. How did the dacron work?