Sealing door access holes for sound deadening

[capnxtreme]

Sup guys,

I've seen lots of different approaches to sealing the inner door skin access holes for sound deadening. I am curious to hear thoughts on one method vs. another--e.g. is cardboard (covered by deadening on both sides) less robust or effective than something stiffer to begin with?

I remember seeing the following ideas mentioned:

1) aluminum roof flashing (?)
2) screen door repair kit
3) cardboard
4) fiberglass

What else? Does it even matter?

I'm personally looking for the quickest/easiest way that would be considered quality, but also curious what would be considered most competition-quality or ultimate. Thanks for any ideas.

[tcguy85]

i used the roof flashing. worked well.

[XC-C30]

Another method is rivetting/welding/screwing stainless steel plates onto the doorframe. Gives tou an almost flat surface to put on deadening mats, thus making it easier to put the doorpanels back in place.

[HondAudio]

There's a lot of different things you can use for this...

1/4" MDF, cut to shape and screwed or glued in place. Make sure to coat it with resin to make it water-resistant.

Plexiglass/lexan/similar. You can hold it in place, trace the exact shape you need with a permanent marker, then attach it the same way as above.

Without testing, I would think that the two materials above would provide the best strength-to-weight ratio. Anything thinner or lighter might flex or even cave in while you're attaching deadening mat.

[89grand]

I used flashing material from Home Depot. It works pretty good and it's pretty cheap.

[XC-C30]

1/4" MDF will flex either, unless you use a bracinbg on the back first (you could do the same to alu, (stainless) steel) in order to give it more strength. heating and rapidly cooling will also help to strengthen it.

[veloze]

I remember using those used real estate "FOR SALE" signs. Very flexible, easy to cut, and in case you have to access inside your doors down the road for some repair, just cut them.

Also, I think ABS sheets will do.

[FrankstonCarAudio]

I always use 4mm (3/16") ABS..

I deaden both sides with 2 layers of Dynamat before fitting to the door with srews ..

Seems to work well, and resistant to moisture..

Mark

[Candisa]

I use the doorpanel itself to seal the door (a few layers of fiberglass on the back side, elastic glue between the door panel and the door), but that only works if your speaker is mounted to the door panel itself.

When the speaker has to be mounted to the framework, I seal the holes with plexi/abs/whatever kind of plastic I can find and is about 1/4" thick (I prefer plexi because it's easy to mark the shape) + elastic glue + a couple of screws + deadening mat

It has no use to seal the holes in the framework when the speaker is mounted to the doorpanel, or to seal the doorpanel to the door when the speaker is mounted to the framework...

greetz,
Isabelle

[tommyd]

I used 1/8" plexiglass. Make sure you have a fine toothed saw otherwise this stuff is impossible to cut with out shattering.

[capnxtreme]

That was my next question: how are you guys cutting all this stuff??

What's the best way to cut the roof flashing?

[FoxPro5]

Heavy duty tin snips will go through that steel sheeting like butter.

If I did my door over again, I'd be using 3/8" HDPE (aka cutting board plastic). Super cheap, waterproof and very dense. Why add more metal to a metal door that you're trying to prevent from resonating?

[ViperVin]

Originally Posted by capnxtreme

That was my next question: how are you guys cutting all this stuff??

What's the best way to cut the roof flashing?

x2 on the roof flashing. I just used scissors to cut mine.

You can layer the flashing to make it as rigid as you want, then apply the sound deadener on top as the last step.

[GenPac]

Originally Posted by veloze

I remember using those used real estate "FOR SALE" signs. Very flexible, easy to cut, and in case you have to access inside your doors down the road for some repair, just cut them.

x2

Cam2XRunner showed me this trick when we sound deadened my truck. With all the houses on the market today, there's PLENTY of signs to be had!
I forget what they called it, but it had a specific name...

EDIT: Found it Coroplast or, Corrugated Plastic.

[capnxtreme]

Hahaha so the real estate signs are made from corrugated plastic?

I'm sure my buddies would be down for some sign heists, LOL.

[GenPac]

Yeah, it's like corrugated cardboard, but well... plastic. It's waterproof, light and fairly strong/stiff yet easy to cut with a razor. I cut it to about 105% of the access hole it was filling then put sound deadener over the top of it. Using the deadener to keep it in place.
If you ever need to get in the door, just trace the edges of the access hole with a razor and out it comes.

Just one option, as all the other suggestions will work also.

[veloze]

Originally Posted by GenPac

x2

Cam2XRunner showed me this trick when we sound deadened my truck. With all the houses on the market today, there's PLENTY of signs to be had!
I forget what they called it, but it had a specific name...

EDIT: Found it Coroplast or, Corrugated Plastic.

X2 Good find GenPac. I went to a couple of RE offices, then I walk out with about 4 signs. It save me a penny or so by not buying the ABS or plexi-glass stuff.

[dbiegel]

You know it's a sad day for the economy when most of the people going into real estate offices are just there to pick up used "for sale" signs to use as corrugated plastic.

Seriously though, I wish I heard of this before I sealed my doors.

I just used a bunch of Raammat on the back side, and then attached Raammat on the front side to it. I've used this method before with good results, because the butyl attaches to the butyl and forms a strong bond which won't come apart, it cant resonate, and its easy to get a full seal around the edges.

What are the drawbacks of using this method? Why is more stiffness important?

[capnxtreme]

Originally Posted by DOMN8R

You know it's a sad day for the economy when most of the people going into real estate offices are just there to pick up used "for sale" signs to use as corrugated plastic.

LOL! Seriously though, I think that's the idea I'll run with.

Thanks guys!

[GenPac]

Originally Posted by DOMN8R

What are the drawbacks of using this method? Why is more stiffness important?

It's just a means of structure for sealing it up. Your method, i'm sure, is just as effective.

[HondAudio]

Coroplast, by itself, is probably very light. Good for weight savings