Undercoating

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skipvair
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Undercoating

Post by skipvair »

Any comments on using rubberized undercoating inside doors for additional soundproofing and rust resistance?


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Frank Metasavage

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terribleted
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Re: Undercoating

Post by terribleted »

treat rust first and be sure not to fill drain holes.
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JasonL
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Re: Undercoating

Post by JasonL »

I used it and it did not make much of a difference. I also covered the door panel papers with 1/6 rubberized plastic sound absorb-er.
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terribleted
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Re: Undercoating

Post by terribleted »

If you really want to cut sound use a butyl based sound mat like RAAMmat.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
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lostboy
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Re: Undercoating

Post by lostboy »

terribleted wrote:If you really want to cut sound use a butyl based sound mat like Raamat.
I used (not in my corvair) the roof repair mat that they sell at Home Depot. It works very well and has very close properties to dynamat at about 1/4 of the price. Even in 100degree temps it stays firm and doesn't drip.


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1961 Corvair 700 Sedan (80hp 3spd Gasoline Heat)
66vairguy
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Re: Undercoating

Post by 66vairguy »

The Home Depot roofing material has been used INSIDE the car for sound reduction and folks complain about the smell. Cheap, but stinks up the car.

The Dynamat pads are expensive, but you only use them once and I've never had a problem with them.

There are other sound mats sold that try to compete with Dynamat, but the most common complaint on the forums (boom box crowd) was the cheaper mats turned to goo and came loose in hot weather.

The "rubberized", and most spray can undercoating, do little to stop noise.
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terribleted
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Re: Undercoating

Post by terribleted »

lostboy wrote: Wed May 24, 2017 7:21 am
terribleted wrote:If you really want to cut sound use a butyl based sound mat like Raamat.
I used (not in my corvair) the roof repair mat that they sell at Home Depot. It works very well and has very close properties to dynamat at about 1/4 of the price. Even in 100degree temps it stays firm and doesn't drip.


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I did a whole car with RAAMmat. a number of years ago. It was way cheaper than Dynamat and performed more like SuperDynamat. Stuck really well (do not let it touch where you do not want it to stay), no issues with sagging. Other materials may be fine but I would certainly steer away from anything tar based or otherwise smelly.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/

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skipvair
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Re: Undercoating

Post by skipvair »

Thanks. Thought about the home depot stuff too, but figured it would get soft and fall off. If buying the real stuff do u piut it on the inside of exterior door skin, or behind door panels?
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lostboy
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Re: Undercoating

Post by lostboy »

terribleted wrote:
lostboy wrote: Wed May 24, 2017 7:21 am
terribleted wrote:If you really want to cut sound use a butyl based sound mat like Raamat.
I used (not in my corvair) the roof repair mat that they sell at Home Depot. It works very well and has very close properties to dynamat at about 1/4 of the price. Even in 100degree temps it stays firm and doesn't drip.


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I did a whole car with RAAMmat. a number of years ago. It was way cheaper than Dynamat and performed more like SuperDynamat. Stuck really well (do not let it touch where you do not want it to stay), no issues with sagging. Other materials may be fine but I would certainly steer away from anything tar based or otherwise smelly.
The stuff I used has no odor at all. I did an entire civic with it and there is no smell.


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66vairguy
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Re: Undercoating

Post by 66vairguy »

I looked up RAAMat reviews and it is cheaper, BUT - folks complained it was very sticky/gooey and after a few months it came down off roof and vertical panels. Dynamat Xtreme DOES NOT come loose after it sets onto a clean surface - about one day to set . I installed it on my clean and painted roof above the headliner and it's been on there a year and in hot sun several times - no issues.

RAAMat could be fine for floors, but I would not use it in doors or above a headliner or on the underside of a trunk lid.

I'll stay with the Dynamat - works as advertised, no stink, doesn't come loose, doesn't turn to goo and ruin the carpets.
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terribleted
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Re: Undercoating

Post by terribleted »

66vairguy wrote: Wed May 24, 2017 5:23 pm I looked up RAAMat reviews and it is cheaper, BUT - folks complained it was very sticky/gooey and after a few months it came down off roof and vertical panels. Dynamat Xtreme DOES NOT come loose after it sets onto a clean surface - about one day to set . I installed it on my clean and painted roof above the headliner and it's been on there a year and in hot sun several times - no issues.

RAAMat could be fine for floors, but I would not use it in doors or above a headliner or on the underside of a trunk lid.

I'll stay with the Dynamat - works as advertised, no stink, doesn't come loose, doesn't turn to goo and ruin the carpets.
Interesting....I wonder if they changed the product since I used it about 10 years ago. I put it on all vertical surfaces in 2 of my own vehicles and never had it move even with 100+ degree days here in Hotlanta. One car was my 2006 Scion xB that was out in the heat every day. It was very tenacious (sticky) as far as its grab.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/

Located in Snellville, Georgia
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