When to install insulation / sound damping material?

[Noah]

Trying to figure out what to do next.

Is it best to install insulation / sound dampening material on the firewall and interior prior to riveting in the subpanel structure (RV-7), or wait until later? If you install it now, you're going to have to deal with the stuff getting in your way when doing firewall plumbing, avionics wiring, control cable routing, etc. If you wait 'til later, you're going to have to spend more time upside down under the dash. Recommendations?

Thanks & Highest Regards,

[Jaypratt]

Put in just before you rivit the top FWD skin. All wiring and FWF should be done.

[David-aviator]

Don't use it at all. It does not reduce noise that much and it provides a moisture trap in places no one can inspect. I glued it in with 3M spray on glue, on the material and on the skin, it came come loose within a year. I am removing it as it removes itself from the where ever it was glued in.

[Rupester]

I've talked to two different guys at Vans (sorry, can't recall which ones), both of whom recommended against using the insulation/soundstop material. Their reasoning? ... 1)adds weight, 2) is not particularly effective in quieting, 3)if you're in a colder climate, you'll want the heat off the firewall in winter months, and 4) the ventilation in summer months adequately offsets firewall heat gain.
Their opinion(s) were "unambivalent".

[az_gila]

Originally Posted by Rupester

I've talked to two different guys at Vans (sorry, can't recall which ones), both of whom recommended against using the insulation/soundstop material. Their reasoning? ... 1)adds weight, 2) is not particularly effective in quieting, 3)if you're in a colder climate, you'll want the heat off the firewall in winter months, and 4) the ventilation in summer months adequately offsets firewall heat gain.
Their opinion(s) were "unambivalent".

Did that also include sound-proofing on the floor?

gil A

[Pirkka]

I would agree that don't use it at all. For more reason, search the forum with "sound proofing" (just put search from "any date") and you'll get lot discussion why do or do not it...

[videobobk]

Originally Posted by David-aviator

Don't use it at all. It does not reduce noise that much and it provides a moisture trap in places no one can inspect. I glued it in with 3M spray on glue, on the material and on the skin, it came come loose within a year. I am removing it as it removes itself from the where ever it was glued in.

David points out some of the problems you MAY run into, but we did some testing as we installed and found you can get noticeable noise reduction. Read up on it. One thing that helped was to glue aluminum foil to the back side of the material. We also painted that flat black, just for looks. I have had no problems with it coming loose, but don't remember what we put it on with. He is dead on about moisture, and you should consider how you will store this airplane. I just helped rehab a Beech with severe corrosion behind the firewall because of a windshield leak into insulation.

Today I will be removing the floor insulation (hope it doesn't stick THAT well!) and installing carpet from Classic Aero. I believe I will get better sound dampening with it at a full 1" thick. They install with velcro.

IIHITDO, I would insulate, but would consider putting it in with velcro. I would use the Classic carpet for the floor right from the start. Insulation will help with heat as well as sound. Some of the firewall heat is radiant and it helps with that, also. To answer your original question, I would put it in as early as possible as it could be removed if necessary and modified for wiring, etc. These are just my opinions, YMMV.

Bob Kelly

[Jamie]

Originally Posted by videobobk

...Today I will be removing the floor insulation (hope it doesn't stick THAT well!) and installing carpet from Classic Aero. I believe I will get better sound dampening with it at a full 1" thick. They install with velcro. ...

My experience in my -7A (XP-IO360, Hartzell C/S, Vetterman exhaust) is that the Cassic Aero carpet provides considerable sound dampening. I made my first several flights with no carpet and I when I finally flew with carpet I had to keep looking at my engine monitor to make sure I was making full power. It was that much of a difference. I really need to borrow a decibel meter to quantify it, but there was certainly a very noticeable difference between carpet and no carpet.

Just my observations.

[jrvssgl]

Hello

I ordered a classic aero interior package for my RV-7, and looking at my static line that runs down the longeron to the rear, it looks like it could be in the way of the install of the aviator side panels. Should I penetrate the bulkheads lower, say under the armrest to allow more room for the side panels or is there room as is? Any advise on where the static line and wire runs could nicely be run without conflict would be apprecieted.

Thanks in Advance

Jarvis

[Mike S]

I would suggest you at least make cardboard templates now, sure is easier before you get the fuse too far along.

If you do decide to install the sound/heat insulation, having the patterns will make it a lot easier. Figuring out the location for wiring/cable/tubing holes is pretty easy.

Good luck.