Ok, here we go. Sorry to take so long. Had to assemble a new fire rig as the old one was long ago dismantled and recycled, and I decided to allow plenty of cure time for the test materials.
First, the candidates:
Cotronics Resbond 907GF (courtesy of Don Pansier)
Rectorseal Biotherm 100 (courtesy Dan Langhout)
Flamemaster CS1900 (courtesy Dan Langhout)
3M FireBarrier 2000
Permatex Ultra Copper
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Dan,
Sorry, but I'm very late coming to this thread. Thanks to everyone, especially Dan, for all the comments & ideas. I believe, however, that I have one consideration that no one has mentioned yet. How will these products hold up in the presence of aviation fuel and oil??? A great product which dissolves in gasoline or oil is next to worthless it would seem to me.
I ask, because silicone based products like the Permatex Ultra Copper are dissolved by gasoline. As an auto mechanic, I used to regularly use gasoline as a solvent to clean RTV silicone from auto parts. I'm sure many of you will recall the disastrous results pilots have had when they used RTV on carburetor parts. [ A number of forced landing caused by RTV ending up jamming float needles are listed in the archives of this forum]
Since the 3M Fire Barrier 2000 is silicone based, I wonder how it would hold up on the front side of the firewall, where it will be exposed to fuel and oil??
I note that the CS 1900 is listed as "fluid resistant". I believe that this is the sort of consideration that takes place when one designs a product for a specific environment [like an aircraft's FWF]
Perhaps it would be wise to cure these products and submerge them in 100LL and 93 octane auto fuel for a few days to see what happens to them. Obviously, the 3M product is only partly silicone, so perhaps it will hold up? Or maybe the other components in it will fair even worse when combined with fuel?
For those of you who already have Fire Barrier 2000 installed, it may be best to take care when fuel is spilled onto the firewall to clean it off immediately. My experience with fuel and silicone products is that exposure for a short period is not a big problem. Continued contact IS an issue. How about a solvent test Dan??
Perspiring minds want to know!
Charlie Kuss