Looking for safe, white RTV for exterior sealing??

IowaRV9Dreamer · #1 09-22-2009, 10:02 PM

The GA 56 GPS antenna calls for a fillet of "appropriate sealant" to be applied after the antenna is mounted on a painted surface. I've seen A&Ps use a grey RTV type material. I'd like to find a white RTV.

Spruce sells Dow Corning Silastic 732 in white for $6, but the datasheet says "DOW CORNING 732 Multi-Purpose Sealant releases a small amount of acetic acid during cure. This may cause corrosion on some metallic parts or substrates, especially in direct contact or when the cure is carried out in a totally enclosed configuration which would not allow cure by-products to escape."

I'm not sure this totally applies, since the RTV would be on a painted surface (no direct contact) and would not be "totally enclosed"

Spruce also sells a $29

tube of RTV-3145 (in clear or grey only). I think this is what I saw the A&P using. It is billed as "non-corrosive".

Has anyone used the 732 sealant, or maybe has a better alternative (maybe at Lowes?)?

BoilermakerRV · #2 09-22-2009, 10:44 PM

In my work we use a two part GE (maybe formerly GE) product called RTV 577. It is white, but requires a etching\priming agent (ours is pink). I have no idea how much it costs. My guess is it's pretty expensive, but it's high quality.

http://www.mgchemicals.com/products/577.html

tinman · #3 09-23-2009, 04:07 AM

I used 3-M 5200 adhesive/sealant. It takes a long time to cure, but it is good stuff. It is used below waterlines on boats.

WingsOnWheels · #4 09-23-2009, 06:01 AM

Quote:

Originally Posted by tinman

I used 3-M 5200 adhesive/sealant. It takes a long time to cure, but it is good stuff. It is used below waterlines on boats.

The first thing I thought of when I read the initial post was 3M 5200. I have used that stuff many times on watercraft, it is tough as nails.

Rick_A · #5 09-23-2009, 08:13 AM

3M 5200 really good stuff if you never want to remove the antenna. If you ever upgrade the GPS and need to install a new antenna, you'll be cursing the 5200.

If you look for the "sensor safe" RTV's in the auto parts stores, they are acetic acid free. However, since you said the plane is painted the acetic acid in regular RTV should not be an issue.

WingsOnWheels · #6 09-23-2009, 08:33 AM

What about the 50 year 100% silicone calk from Lowes or HD. I don't see why that wouldn't work as just a sealer. Works great in my shower...